Piezoelectric sensors for leaflet capture optimization

Abstract

A system for securing tissue includes a fixation device and a piezoelectric sensing system. The fixation device includes a center portion and a first clamp extending from the center portion. The first clamp is comprised of a first proximal element and a first distal element. The piezoelectric sensing system includes a first piezoelectric sensor coupled to one of the first distal element, the first proximal element, and the center portion. A signal processing unit of the sensing system includes a power source and a signal processing module. The signal processing module is configured to receive signals from the first piezoelectric sensor corresponding to a parameter associated with pressure, process the received signals, and generate an output signal indicative of the parameter. An interface is configured to couple the first piezoelectric sensor to the signal processing unit for transmitting the signals from the first piezoelectric sensor to the signal processing unit.

Description

Atty Docket No. ABTEVA-0063PCTPIEZOELECTRIC SENSORS FOR LEAFLET CAPTURE OPTIMIZATIONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 735,448, filed December 18, 2024, the disclosure of which is incorporated by reference herein in its entirety.BACKGROUND

[0002] The cardiac cycle is divided into two phases — diastole and systole. Diastole is generally characterized by the muscular relaxation of the heart and the filling of its chambers with blood. On the other hand, systole is generally characterized by the muscular contraction of the ventricles which pumps blood from the ventricles to the arteries. During ventricular systole, ventricular pressure increases relative to atrial pressure resulting in the closure of the mitral valve and the tricuspid valve. The mitral valve separates the left atrium from the left ventricle, and the tricuspid valve separates the right atrium from the right ventricle. These valves operate as check valves preventing blood from flowing back into the atria during ventricular contraction. However, valvular insufficiency may appear in one or both of these valves which may result in a regurgitative flow back into the atrium across the affected valve. Such regurgitative flow can be in the form of mitral valve regurgitation (“MVR”) and / or tricuspid valve regurgitation (“TVR”). Left untreated, MVR and TVR can lead to severe health consequences, such as progressive heart failure, cardiac arrhythmias, pulmonary hypertension, stroke, and endocarditis, to name a few.

[0003] MVR and TVR can have a variety of etiologies which typically fall into the categories of degenerative (primary) and functional (secondary) regurgitation. Degenerative valve regurgitation principally occurs due to abnormalities or degeneration of the valve apparatus, such as the valve leaflets, valve annulus, chordae tendineae, and / or papillary muscles. One example of a degenerative valve condition is mitral valve prolapse. Functional valve regurgitation is often a secondary condition that arises from underlying heart conditions or diseases that affect the structure or function of the heart. Examples of conditions that can result in functional regurgitation include dilated cardiomyopathy, ischemic heart disease, pulmonary hypertension, and heart failure. Regardless of the underlying condition precipitating the regurgitative flow, the primary mechanism by which regurgitation occurs is the failure ofAtty Docket No. ABTEVA-0063PCT the valve leaflets to properly and completely seal or coapt during systole which allows a jet of blood to flow back into the atrium between the affected leaflets.

[0004] Treatment options for MVR and TVR generally include Guideline-Directed Medical Therapy (“GDMT”), valve replacement, and valve repair. GDMT usually involves the administration of a combination of drugs that treat an underlying heart condition. Valve replacement and repair may include open-heart surgical options and catheter-based options. Catheter-based repair procedures are sometimes referred to as transcatheter edge-to-edge repair (“TEER”).BRIEF SUMMARY OF THE DISCLOSURE

[0005] In one aspect of the present disclosure, a system for securing tissue includes a fixation device and a piezoelectric sensing system. The fixation device includes a center portion and a first clamp extending outwardly from the center portion. The first clamp includes a first distal element which is moveable between an open and a closed position. The first distal element has a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end. The fixation device also includes a first proximal element which is moveably disposed opposite the first distal element. The first proximal element has a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end of the first proximal element. The piezoelectric sensing system includes a first piezoelectric sensor which is coupled to one of the first distal element, the first proximal element, and the center portion. The sensing system also includes a signal processing unit. The signal processing unit includes a power source and a signal processing module. The signal processing module is configured to receive signals from the first piezoelectric sensor corresponding to a parameter associated with pressure, process the received signals, and generate an output signal indicative of the parameter. The piezoelectric sensing system also includes an interface configured to couple the first piezoelectric sensor to the signal processing unit for transmitting the signals from the first piezoelectric sensor to the signal processing unit.

[0006] In some implementations of the system, the first piezoelectric sensor may be coupled to one of the first proximal element and the first distal element. In one example, the first piezoelectric sensor may be positioned between the midline and the fixed end of either the first proximal element or first distal element. In another example, the first piezoelectric sensor may be positioned at the midline of either the first proximal element or the first distal element.Atty Docket No. ABTEVA-0063PCTIn a further example, the first proximal element may include a plurality of frictional elements extending therefrom, and the first piezoelectric sensor may be coupled to one of the frictional elements. In an even further example, the first proximal element may include a first side portion, a second side portion, and a window disposed between the first and second side portions, and the first piezoelectric element may be disposed on the first side portion. In another example, the first distal element may include an elongate body and first and second wing portions extending laterally outwardly from the elongate body, and the first piezoelectric element may be disposed on the first wing portion.

[0007] In some implementations of the piezoelectric sensing system, the piezoelectric sensing system may further include a second piezoelectric sensor. The second piezoelectric sensor may be coupled to at least one of the first proximal element and first distal element. In one example, the second piezoelectric sensor may be positioned between the free end and the midline of either the first proximal element or the first distal element. In another example, the second piezoelectric sensor may be positioned at the midline of either the first proximal element or the first distal element.

[0008] In some implementations of the piezoelectric sensing system, the piezoelectric sensing system may include a sensor array, and the first and second piezoelectric sensors may be included in the sensor array. In one example, the first and second piezoelectric sensor in the array may each include a piezoelectric element and first and second electrodes positioned at opposite sides of the piezoelectric element. Additionally, the sensor array may include an encapsulation enclosing both the first and second piezoelectric sensors. The piezoelectric element of each of the first and second piezoelectric sensors may be made from one of quartz, lead zirconate titanate (PZT), barium titanate, and polyvinylidene fluoride (PVDF). Further, the sensor array may include a first lead, a second lead, and a third lead. The first lead may be coupled to the first electrode of each of the first and second piezoelectric sensors. The second lead may be coupled to the second electrode of the first piezoelectric sensor. The third lead may be coupled to the second electrode of the second piezoelectric sensor.

[0009] In some implementations of the piezoelectric sensing system, the first piezoelectric sensor may be a strip sensor. The strip sensor may have a width and a length. The length of the first piezoelectric sensor being at least twice the width. In one example, the piezoelectric sensor may be coupled to one of the first proximal element and first distal element such that the first piezoelectric sensor extends along a length extending from the midline toAtty Docket No. ABTEVA-0063PCT75% of the length as measured from the free end thereof. In another example, the first piezoelectric sensor is coupled to one of the first proximal element and first distal element and extends along a length extending from the midline to the fixed end thereof. The first piezoelectric sensor may have a piezoelectric element that is made from PVDF.

[0010] In some implementations of the piezoelectric system, the piezoelectric sensing system may further include a second piezoelectric sensor. The second piezoelectric sensor may be a strip sensor that has a width and a length. The length of the second piezoelectric sensor may be at least twice the width. In one example, the second piezoelectric sensor may be coupled to one of the first proximal element and first distal element and may extend along a length extending from the midline to 25% of the length as measured from the free end thereof. In another example, the second piezoelectric sensor may be coupled to one of the first proximal element and first distal element and may extend along a length extending from the free end to the midline thereof.

[0011] In some implementations of the fixation device, the center portion may include a coupling member that may be configured to be releasably coupled to a delivery catheter. The first piezoelectric sensor may be coupled to the coupling member.

[0012] In other implementations of the fixation device, the center portion may include a compressible coaptation body extending radially outwardly relative to a longitudinal axis of the fixation device. The compressible coaptation body may be compressible radially inwardly, and the first piezoelectric sensor may be coupled to the coaptation body.

[0013] In either implementation of the center portion, a second piezoelectric sensor may be coupled to the center portion. Further a first plane may bisect the center portion and a second plane may be oriented perpendicular to the first plane and may intersect the first clamp. In one example, the first and second piezoelectric sensors may be disposed at opposite sides of the center portion between the first and second planes. In another example, the first piezoelectric sensor may be a strip sensor having a length and a width. The length of the first piezoelectric sensor may be at least twice the width, and the first piezoelectric sensor may extend about at least a portion of a perimeter of the center portion.

[0014] In some implementations of the system, the system may further include a delivery system. The delivery system may include a delivery handle and a delivery catheter extending from the delivery handle. In one example, the signal processing unit may be disposed within the delivery handle. Additionally, the interface may be a hardwired interface extendingAtty Docket No. ABTEVA-0063PCT from the first piezoelectric sensor, through the delivery catheter, and to the signal processing unit within the handle. In one example of the interface, the delivery catheter may include a shaft. The shaft may have a plurality of spring arms each with a first electrical terminal and an actuator rod extendable through the shaft. The center portion of the fixation device may include a coupling member that may have second electrical terminals corresponding with the first electrical terminals. Moving the actuator rod in a first direction may urge the spring arms into engagement with the coupling member and the first electrical terminals into engagement with the second electrical terminals. Conversely, moving the actuator rod in a second direction may disengage the spring arms from the coupling member and the first electrical terminals from the second electrical terminals. Additionally, the delivery system may include a first proximal element line extending from the delivery catheter and may be releasably coupled to the first proximal element. In another example of the interface, the first proximal element line is comprised of insulated wiring and is configured to electrically couple the first piezoelectric sensor to the signal processing unit. Further, the delivery handle may include an LED array having an LED associated with the first piezoelectric sensor.

[0015] In another aspect of the present disclosure, a system for securing tissue includes a delivery system, a fixation device, and a first piezoelectric ultrasonic transducer. The delivery system includes a delivery handle and a delivery catheter extending from the delivery handle. The fixation device is releasably coupled to the delivery catheter and includes a center portion and a first clamp extending outwardly from the center portion. The first clamp includes a first distal element which is moveable between an open position and a closed position. The first distal element has a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end. The first clamp also includes a first proximal element which is moveably disposed opposite the first distal element. The first proximal element has a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end of the first proximal element. The first piezoelectric ultrasonic transducer is coupled to the delivery catheter and is configured to emit ultrasonic waves toward the first clamp when the first distal element is in the open position and receive reflected waves from the first clamp when in the open position.

[0016] In some implementations of the first piezoelectric ultrasonic transducer, the first piezoelectric ultrasonic transducer may have a first position in which the first piezoelectric ultrasonic transducer is nested within the delivery catheter, and a second position in which theAtty Docket No. ABTEVA-0063PCT first ultrasonic transducer is extended from the delivery catheter in a direction toward the first clamp when the first distal element is in the open position.

[0017] In some implementations of the fixation device, the fixation device may include a second clamp. The second clamp may include a second distal element and a second proximal element. The fixation device may also include a second piezoelectric ultrasonic transducer coupled to the delivery catheter. The second piezoelectric ultrasonic transducer may be configured to emit ultrasonic waves toward the second clamp when the second distal element is in the open position and receive reflected waves from the second clamp when the second distal element is in the open position. The second piezoelectric ultrasonic transducer may have a first position in which the second piezoelectric ultrasonic transducer is nested within the delivery catheter, and a second position in which the second ultrasonic transducer is extended from the delivery catheter in a direction toward the second clamp when the second distal element is in the open position.

[0018] In some implementations of the system, the system may include a signal processing unit. The signal processing unit may have a power source and a signal processing module. The signal processing module may be configured to receive signals from the first piezoelectric sensor corresponding to the reflected waves, process the received signals, and generate an output signal indicative of reflected waves. In one example, the output signal is an M-mode signal.

[0019] In some implementations of the system, the system may further include a first piezoelectric pressure sensor coupled to one of the first distal element, the first proximal element, and the center portion. In one example, the first piezoelectric sensor may be coupled to one of the first proximal element and first distal element and may be positioned between the midline and the fixed end thereof. In another example, the first piezoelectric sensor may be coupled to one of the first proximal element and the first distal element and positioned at the midline thereof.

[0020] In further implementations of the system, the system may further include a second piezoelectric sensor. The second piezoelectric sensor may be coupled to at least one of the first proximal element and first distal element and may be positioned between the free end and the midline thereof. In one example, the second piezoelectric sensor may be coupled to one of the first proximal element and the first distal element and may be positioned at the midline thereof. In a further example, the first proximal element may include a plurality of frictionalAtty Docket No. ABTEVA-0063PCT elements extending therefrom, and the first piezoelectric sensor may be coupled to one of the frictional elements. In another example, the first proximal element may include a first side portion, a second side portion, and a window disposed between the first and second side portions, and the first piezoelectric element may be disposed on the first side portion. In an even further example, the first distal element may include an elongate body and first and second wing portions extending laterally outwardly from the elongate body, and the first piezoelectric element may be disposed on the first wing portion.

[0021] In a further aspect of the present disclosure, a system for securing tissue includes a delivery catheter having a shaft, a fixation device, and a sensor package. The fixation device is releasably coupled to the shaft and includes a center portion, a first clamp extending outwardly from the center portion and having a first distal element and a first proximal element, and a second clamp extending outwardly from the center portion and having a second distal element and a second proximal element. The sensor package is disposed at a distal end of the shaft and includes a sensor-bearing surface and a first sensor array disposed on the sensorbearing surface and directed toward the first clamp. The first sensor array includes one or more piezoelectric sensors configured to emit ultrasonic waves toward the first proximal element and receive reflected waves therefrom.

[0022] In some implementations of the system, the system may further include a ring coupled to the delivery catheter, and the shaft may extend through the ring. The ring may include a head having a cavity, and the sensor package may be disposed within the cavity such that the sensor-bearing surface is exposed at a distal side of the ring. The ring may include a major lumen for passage of the shaft and a plurality of minor lumens arranged about the major lumen for passage of at least one sensor wire and at least one proximal element line for actuating the first proximal element. The ring may be coupled to the delivery catheter such that the ring rotates with the delivery catheter, and the first sensor array may maintain rotational alignment with the first proximal element.

[0023] In some implementations of the sensor package, the sensor package may further include a second sensor array disposed on the sensor-bearing surface and directed toward the second clamp.

[0024] In some implementations of the sensor package, the sensor-bearing surface may include a dome surface. The dome surface may be curved in both a first plane parallel to a central axis of the sensor package and a second plane perpendicular to the central axis.Atty Docket No. ABTEVA-0063PCT

[0025] In other implementations of the sensor package, the sensor-bearing surface may include a first conical surface and a second conical surface extending circumferentially about a central axis of the sensor package. The first conical surface may be disposed at a first angle relative to the central axis, and the second conical surface may be disposed at a second angle relative to the central axis. The first angle may be greater than the second angle. The first and second conical surfaces may be curved in a plane perpendicular to the central axis but may have a linear profile in a plane parallel to the central axis.

[0026] In further implementations of the sensor package, the sensor-bearing surface may include a first planar surface angled toward the first clamp, and the sensor package may further include a second planar surface angled toward the second clamp. The first and second planar surfaces may form a V-shape. In the V-shape configuration, the planes of the first and second planar surfaces may converge, but the surfaces themselves may not converge. However, in other examples, the surfaces themselves may converge.

[0027] In some implementations of the system, the first proximal element may have a first width defined between side edges thereof, and the first sensor array may have a second width greater than the first width such that the first sensor array extends beyond the side edges of the first proximal element.

[0028] In some implementations of the system, the one or more piezoelectric sensors may include piezoelectric micromachined ultrasonic transducers.

[0029] In some implementations of the system, the system may further include a signal processing unit configured to receive signals from the first sensor array and generate an output signal. The output signal may be one of a B-scan signal, an M-scan signal, and a tissue capture indicator signal.

[0030] In some implementations of the system, the first sensor array may be configured to direct ultrasonic beams toward a detection zone. The detection zone may be a region where the first sensor array is configured to observe tissue. The detection zone may have a width component and a length component defined by a direction in which the ultrasonic beams are emitted from the first sensor array. The width component and the length component may be a function of dimensions of the first sensor array and angles at which the one or more piezoelectric sensors are oriented. The angles at which the one or more piezoelectric sensors are oriented may be a function of a geometry of the sensor-bearing surface.Atty Docket No. ABTEVA-0063PCT

[0031] In some implementations of the detection zone, the first proximal element may have side edges and may be formed from a solid metal structure, and the detection zone may be focused at and / or adjacent to the side edges of the first proximal element. The width component may be defined as an extent to which the detection zone extends transversely beyond the side edges of the first proximal element. A collective width component of the detection zone may extend beyond both side edges of the first proximal element by a total distance corresponding to about 25% to about 75% of a width of the first proximal element.

[0032] In some implementations of the detection zone, the first proximal element may have a length defined between a fixed end and a free end thereof, and the length component of the detection zone may be defined relative to the length of the first proximal element. In one example, the length component may extend along an entire length of the first proximal element. In another example, the length component may extend along less than the entire length of the first proximal element. For example, the length component may overlap with about 50% of the length of the first proximal element as measured from the free end thereof. In other examples, the length component may overlap with about 25% to about 75% of the length of the first proximal element as measured from the free end thereof. Assessing tissue presence along the length component may allow tissue insertion depth to be evaluated to ensure tissue is properly grasped within the gripper to prevent leaflet detachment.BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG. 1 A is a cross-sectional representation of a heart illustrating its four valves.

[0034] FIG. IB is a cross-sectional representation of a heart illustrating the left ventricle and left atrium during systole.

[0035] FIG. 2A is a schematic view of a mitral valve during normal coaptation.

[0036] FIG. 2B is a schematic view of a mitral valve during regurgitate coaptation.

[0037] FIGS. 3A and 3B are schematic views of a fixation device according to an embodiment of the present disclosure grasping leaflets of a mitral valve.

[0038] FIG. 4A is a perspective view of a fixation device according to another embodiment of the present disclosure.

[0039] FIG. 4B is a perspective view of the fixation device of FIG. 4A including a covering.

[0040] FIG. 5A is a perspective view of a gripping device of the of the fixation device of FIG. 4A according to an embodiment of the present disclosure.Atty Docket No. ABTEVA-0063PCT

[0041] FIG. 5B is an elevational view of the gripping device of FIG. 5 A.

[0042] FIG. 6A is a perspective view of a gripping device according to another embodiment of the present disclosure.

[0043] FIG. 6B is a partial schematic view of the gripping device of FIG. 6A coupled to a distal element of the fixation device of FIG. 4A.

[0044] FIG. 6C is a partial schematic view of a gripping device according to an alternative embodiment of the present disclosure coupled to a distal element according to an alternative embodiment of the present disclosure.

[0045] FIG. 7A is an elevational view of a coupling system according to an embodiment of the present disclosure for coupling the fixation device of FIG. 4A and a delivery system.

[0046] FIGS. 7B and 7C are schematic views of the coupling system of FIG. 7A in respective first and second configurations.

[0047] FIGS. 8A and 8B are schematic cross-sectional views of a coupling system according to another embodiment of the present disclosure for coupling a fixation device, such as the fixation device of FIG. 4A, and a delivery system.

[0048] FIGS. 9A-9B, 10A-10B, 11 A-1 1B, 12A-12B and 13A-13C illustrate the fixation device of FIG. 4A in various possible positions during introduction and placement of the device within a mammalian body to perform a therapeutic procedure.

[0049] FIG. 14 is a perspective view of the fixation device of FIG. 4A including a lock according to an embodiment of the present disclosure and illustrating a plurality of proximal element lines and a lock line coupled to the fixation device.

[0050] FIG. 15 is an elevational view of the lock and proximal elements of the fixation device of FIG. 14 and illustrating a lock line and single proximal element line respectively coupled thereto.

[0051] FIG. 16 is a schematic view of the fixation device of FIG. 4A coupled to a delivery system and illustrating a plurality of proximal element lines coupled to a shaft of the delivery system.

[0052] FIGS. 17A and 17B are partial enlarged views of a distal end portion of the delivery system shaft of FIG. 16 according to an embodiment of the present disclosure.

[0053] FIG. 17C is a cross-sectional view of the delivery system shaft taken along line C-C of FIG. 17B.Atty Docket No. ABTEVA-0063PCT

[0054] FIG. 17D is a partial perspective view of a distal end portion of one of the proximal element lines of FIG. 16 including a catch according to an embodiment of the present disclosure.

[0055] FIG. 17F is a partial elevational view of the delivery system shaft of FIG. 17A having holes configured to receive the catch of FIG. 17D.

[0056] FIG. 17F is a partial elevational view of the delivery system shaft of FIG. 17A and an actuator rod disposed therein intersecting the holes of the delivery system shaft.

[0057] FIG. 17G is a partial elevational view of a distal end portion of one of the proximal element lines of FIG. 16 including a catch according to another embodiment of the present disclosure.

[0058] FIG. 18A is an enlarged cross-sectional view of the lock of FIG. 14 taken along a midline thereof and in an unlocked configuration.

[0059] FIG. 18B is an enlarged elevational view of the lock of FIG. 14 and in a locked configuration.

[0060] FIG. 18C is a perspective view of a release harness of the lock of FIG. 14.

[0061] FIG. 19A is an elevational view of a lock of the fixation device of FIG. 4A according to another embodiment of the present disclosure.

[0062] FIG. 19B is a transparent perspective view of a binding plate of the lock of FIG. 19 A.

[0063] FIG. 19C is an enlarged elevational view of the lock of FIG. 19A.

[0064] FIGS. 20A and 20B are schematic pinch force diagrams along proximal and distal elements of different lengths.

[0065] FIG. 21 is a schematic view of a piezoelectric sensing system according to an embodiment of the present disclosure.

[0066] FIG. 22A is a schematic top view of a piezoelectric sensor according to an embodiment of the present disclosure.

[0067] FIG. 22B is a cross-sectional schematic view of the piezoelectric sensor of FIG. 22A.

[0068] FIG. 23A is a schematic perspective view of a sensor array according to an embodiment of the present disclosure and including a plurality of piezoelectric sensors.

[0069] FIG. 23B is a schematic exploded view of an exemplary sensor of the sensor array of FIG. 23 A.Atty Docket No. ABTEVA-0063PCT

[0070] FIG. 24 is a schematic view of a distal end of an interventional system according to an embodiment of the present disclosure and including an exemplary fixation device having one or more piezoelectric sensors coupled thereto.

[0071] FIG. 25 is a bottom view of a proximal element according to an example of the fixation device of FIG. 24.

[0072] FIG. 26 is a bottom view of a proximal element according to another example of the fixation device of FIG. 24.

[0073] FIG. 27 is a bottom view of a proximal element according to a further example of the fixation device of FIG. 24.

[0074] FIG. 28 is a bottom view of a proximal element according to another example of the fixation device of FIG. 24.

[0075] FIG. 29 is a bottom view of a proximal element according to a further example of the fixation device of FIG. 24.

[0076] FIG. 30 is a partial bottom view of a proximal element according to another example of the fixation device of FIG. 24.

[0077] FIG. 31 is a partial bottom view of a proximal element according to a further example of the fixation device of FIG. 24.

[0078] FIG. 32 is a bottom view of a proximal element according to another example of the fixation device of FIG. 24.

[0079] FIG. 33 is a bottom view of a proximal element according to a further example of the fixation device of FIG. 24.

[0080] FIG. 34 is a perspective view of a proximal element according to another example of the fixation device of FIG. 24.

[0081] FIG. 35 is a perspective view of a distal element according to an example of the fixation device of FIG. 24.

[0082] FIG. 36 is a schematic view of a center portion according to an example of the fixation device of FIG. 24.

[0083] FIG. 37 is a schematic view of a catheter according to an example of the interventional device of FIG. 24.

[0084] FIG. 38 is a schematic view of a center portion according to another example of the fixation device of FIG. 24.Atty Docket No. ABTEVA-0063PCT

[0085] FIG. 39 is a schematic cross-sectional view representative of the examples of FIGS. 36-38 and in accordance with one example thereof.

[0086] FIG. 40A is a perspective view of a piezoelectric sensor according to a further embodiment of the present disclosure.

[0087] FIG. 40B is a schematic cross-sectional view of the piezoelectric sensor of FIG. 40A.

[0088] FIG. 41 is a schematic view of a distal end of an interventional system according to another embodiment of the present disclosure and including an exemplary implantable fixation device having one or more piezoelectric sensors coupled thereto.

[0089] FIG. 42 is a bottom view of a proximal element according to an example of the fixation device of FIG. 41.

[0090] FIG. 43 is a bottom view of a proximal element according to another example of the fixation device of FIG. 41.

[0091] FIG. 44 is a bottom view of a proximal element according to a further example of the fixation device of FIG. 41.

[0092] FIG. 45 is a perspective view of a proximal element according to another example of the fixation device of FIG. 41 .

[0093] FIG. 46 is a perspective view of a distal element according to an example of the fixation device of FIG. 41.

[0094] FIG. 47 is a schematic view of a center portion according to an example of the fixation device of FIG. 41 .

[0095] FIG. 48 is a schematic view a catheter according to an example of the interventional system of FIG. 41.

[0096] FIG. 49 is a schematic view of a center portion according to another example of the fixation device of FIG. 41.

[0097] FIG. 50 is a schematic cross-sectional view representative of the examples of FIGS. 47-49 and in accordance with one example thereof.

[0098] FIG. 51 is a schematic view of a piezoelectric sensor according to another embodiment of the present disclosure.

[0099] FIG. 52 is a schematic view of a distal end of an interventional system according to a further embodiment of the present disclosure and including one or more of the piezoelectric sensors of FIG. 51.Atty Docket No. ABTEVA-0063PCT

[0100] FIG. 53 is a schematic view of a distal end of an interventional system according to another embodiment of the present disclosure and including one or more of the piezoelectric sensors of FIG. 51.

[0101] FIG. 54 is a perspective view of an interventional system according to a further embodiment of the present disclosure.

[0102] FIG. 55 is a perspective view of gripper element lines according to an example of the interventional system of FIG. 54.

[0103] FIGS. 56A and 56B are partial cross-sectional views of an interventional system coupling according to an example of the interventional system of FIG. 54.

[0104] FIG. 57 is a block diagram of an exemplary method of the present disclosure.

[0105] FIG. 58 A is a front elevational view of a ring and a sensor package according to an embodiment, and also showing a catheter shaft and a fixation device coupled to the catheter shaft.

[0106] FIG. 58B is a bottom perspective view of the ring, sensor package, and fixation device of FIG. 58A.

[0107] FIG. 58C is a bottom view of the ring of FIG. 58A.

[0108] FIG. 58D is a perspective view of the ring of FIG. 58A with a partial catheter shaft extending therethrough.

[0109] FIG. 58E is a front elevational view of the ring and sensor package of FIG. 58A with a first fixation device having a first clamp length coupled to a distal shaft of a delivery catheter and illustrating a first standoff distance between the ring and fixation device.

[0110] FIG. 58F is a front elevational view of the ring and sensor package of FIG. 58A with a second fixation device having a second clamp length coupled to a distal shaft of a delivery catheter and illustrating a standoff distance between the ring and second fixation device.

[0111] FIG. 58G is a front elevational view of the sensor package of FIG. 58A.

[0112] FIG. 58H is a partial perspective view of the ring and sensor package of FIG.58 A in an exploded configuration with a catheter shaft extending therethrough.

[0113] FIG. 581 is a partial perspective view of the ring and sensor package of FIG. 58A in an assembled configuration.

[0114] FIG. 59A is a bottom perspective view of a ring with a sensor package according to another embodiment of the present disclosure.Atty Docket No. ABTEVA-0063PCT

[0115] FIG. 59B is a bottom view of the ring and sensor package of FIG. 59A illustrating a relationship of sensor arrays relative to a gripping device having first and second proximal elements.

[0116] FIG. 60 is a bottom perspective view of a ring with a sensor package according to a further embodiment of the present disclosure, and also showing a catheter shaft and a fixation device coupled to the catheter shaft.

[0117] FIG. 61 A is a front elevational view of a sensor package according to another embodiment of the present disclosure.

[0118] FIG. 61B is a bottom perspective view of a ring and the sensor package of FIG. 61A.

[0119] FIG. 61 C is a bottom view of the ring and sensor package of FIG. 61 A illustrating a relationship of sensor arrays relative to a gripping device having first and second proximal elements.

[0120] FIG. 62A is a bottom perspective view of a ring with a sensor package according to a further embodiment of the present disclosure, and also showing a catheter shaft and a fixation device coupled to the catheter shaft.

[0121] FIG. 62B is a front elevational view of the ring and sensor package of FIG. 62A with a partial catheter shaft extending therethrough.

[0122] FIG. 62C is a bottom perspective view of the ring and sensor package of FIG. 62A with a partial catheter shaft extending therethrough.

[0123] FIG. 62D is another perspective view of the ring and sensor package of FIG. 62A.

[0124] FIG. 63 is a B-scan ultrasound image illustrating an exemplary display output for tissue detection according to an embodiment of the present disclosure, the B-scan image showing a sector scan view with grayscale representation of tissue density.

[0125] FIG. 64 is an M-scan ultrasound image illustrating an exemplary display output for tissue detection according to an embodiment of the present disclosure, the M-scan image showing tissue motion over time across multiple cardiac cycles.

[0126] FIG. 65 is an ultrasound image illustrating an exemplary tissue capture indicator display according to an embodiment of the present disclosure, the image showing a depth scale, a region of low attenuation corresponding to liquid, and a solid white block region of high attenuation corresponding to a solid clip.Atty Docket No. ABTEVA-0063PCTDETAILED DESCRIPTION

[0127] The valves of a normal heart H are illustrated in FIGS. 1A and IB. These valves include the mitral valve MV, the tricuspid valve TV, the aortic valve AV, and the pulmonary valve PV. The mitral valve MV separates the left atrium LA and the left ventricle LV, and the tricuspid valve TV separates the right atrium RA and the right ventricle RV. The mitral valve MV and the tricuspid valve TV are sometimes referred to as the atrioventricular valves. The mitral valve MV is a bicuspid valve in that it has two leaflets referred to as the posterior leaflet PL and the anterior leaflet AL. The tricuspid valve TV typically has three leaflets referred to as the anterior leaflet AL, the posterior leaflet PL, and the septal leaflet SL. However, studies have shown that, although the TV is typically composed of three leaflets of unequal size, in many cases, two or more than three leaflets may be present as anatomic variants in healthy subjects. Thus, reference herein to the tricuspid valve TV should be understood to refer to the atrioventricular valve located between the right atrium RA and right ventricle RV regardless of the number of leaflets be it two, three, or more than three leaflets. However, exemplary embodiments discussed herein refer to the usual anatomic structure of the tricuspid valve TV that includes three leaflets.

[0128] As illustrated in FIG. IB, the anterior leaflet AL and posterior leaflet PL of the mitral valve MV extend from a valve annulus AN to respective free edges FE. The free edges FE are secured to the lower portions of the left ventricle LV through chordae tendineae CT (referred to hereinafter as the chordae). The chordae CT include a plurality of branching tendons that are attached to papillary muscles PM at the lower portions of the left ventricle LV and extend upwardly to the lower surfaces of each of the valve leaflets where they are attached. The three leaflets of the tricuspid valve TV similarly extend from a valve annulus AN to respective free edges FE which are secured via chordae to the papillary muscles of the right ventricle RV.

[0129] The mitral valve MV depicted in FIGS. IB and 2A illustrate the proper functioning of an atrioventricular valve during ventricular systole. As the ventricles contract, the free edges FE of adjacent leaflets LF meet along a line of coaptation LOC. The joinder of the leaflets LF at this line of coaptation LOC seals off the ventricle from the atrium and prevents the back flow of blood or “regurgitation” from entering into the atrium. Thus, with the right atrium RA and left atrium LA respectively sealed off by the mitral valve MV and tricuspidAtty Docket No. ABTEVA-0063PCT valve TV, blood in the left ventricle LV can only flow through the aortic valve AV to the body, and blood in the right ventricle RV can only flow through the pulmonary valve PV to the lungs.

[0130] A number of structural defects in the heart H can cause mitral valve regurgitation (“MVR”) and / or tricuspid valve regurgitation (“TVR”). MVR and TVR occur when their respective leaflets LF do not close properly allowing leakage from the ventricle into the atrium. The mitral valve MV depicted in FIG. 2B illustrates valvular insufficiency of an atrioventricular valve resulting in regurgitation. In the depicted example, an enlargement of the heart H may cause the valve annulus AN to become enlarged, making it impossible for the free edges FE of the valve leaflets LF to meet during systole. This may result in a gap G between the leaflets LF which allows blood to leak through the valve. In another example, ruptured or elongated chordae CT can cause a valve leaflet LF to prolapse at least due to inadequate tension transmitted to the leaflet via the chordae CT. While an adjacent leaflet LF may maintain a normal profile, the prolapsing leaflets LF may flail about preventing the proper joinder between the leaflets LF resulting in leakage into the atrium. In a further example, regurgitation can occur in patients who have suffered ischemic heart disease which may result in weak ventricular contractions insufficient to effect proper closure.

[0131] The present disclosure describes exemplary systems, devices, and methods for percutaneously repairing a valve to treat cardiac valve regurgitation, particularly MVR and TVR. When referring to such disclosed systems, devices, and methods, the term "proximal" (P) shall mean closer to the user or in a direction toward a device to be manipulated by the user outside the patient’s body, and the term "distal" (D) shall mean more distant from the user or in a direction toward a device that is positioned at the treatment site within the patient’ s body (e.g., fixation device 112). With respect to the mitral valve and tricuspid valve, “proximal” shall refer to the atrial or upstream side of the valve leaflets, and “distal” shall refer to the ventricular or downstream side of the valve leaflets.

[0132] FIGS. 3 A and 3B depict a fixation device 12, according to an embodiment of the present disclosure, grasping leaflets LF of an atrioventricular valve, which is illustrated as a mitral valve MV. Fixation device 12 may be releasably coupled to a distal end of a shaft 11 of a delivery system to form an interventional tool 10. Fixation device 12 may include distal elements 20 (also referred to herein as fixation elements) and proximal elements 40 (also referred to herein as gripping elements). Distal and proximal elements 20, 40 may be moveable relative to each other and may protrude radially outward relative to a longitudinal axis Al ofAtty Docket No. ABTEVA-0063PCT fixation device 12. As shown in FIG. 3 A, fixation device 12 may be positionable on opposite sides of adjacent leaflets LF of the valve so as to capture or retain the leaflets LF therebetween. In this regard, proximal elements 40 may be positioned at a proximal side of the valve leaflets LF, and distal elements 20 may be positioned on a distal side of the valve leaflets LF. Proximal elements 40 may be made from cobalt chromium, nitinol, or stainless steel, for example, and distal elements 20 may be made from cobalt chromium or stainless steel, for example.

[0133] Fixation device 12 may be releasably coupled to shaft 11 such that it can be detached and left behind as an implant to hold the leaflets LF together in the coapted position. In this regard, fixation device 12 may be delivered to a target valve percutaneously using any one of a number of different approaches, such as via a transfemoral, a transapical, or a transjugular approach, for example. Thus, in one example of treating MVR, fixation device 12 may be delivered to the deficient mitral valve MV using a transfemoral approach in which fixation device 12 is guided through the inferior vena cava IVC (see FIG. 1A), across the interatrial septum S, and into left atrium LA where fixation device 12 is advanced into the mitral valve MV. Also, in one example of treating TVR, fixation device 12 may be guided transfemorally through the inferior vena cava IVC to the right atrium RA where fixation device 12 is advanced to a desired position within the tricuspid valve TV.

[0134] FIG. 3B is an atrial-side view of fixation device 12 in one example of a desired orientation in relation to adjacent leaflets LF of an atrioventricular valve, such as the depicted mitral valve MV. The distal and proximal elements 20, 40 are positioned to be substantially perpendicular to the line of coaptation LOC. Thus, in the case of a mitral valve MV, fixation device 12 may be oriented perpendicular (+ / - 5 degrees) to a line of coaptation LOC between the posterior leaflet PL and anterior leaflet AL, and in the case of a tricuspid valve TV, fixation device 12 may be positioned perpendicular (+ / - 5 degrees) to a line of coaptation between the septal leaflet SL and the anterior leaflet AL, the septal leaflet SL and the posterior leaflet PL, or the anterior leaflet AL and the posterior leaflet PL, for example. Device 12 may be moved roughly along the line of coaptation LOC to the location of regurgitation. The leaflets LF may be held in place so that, during diastole, the leaflets LF remain in position between elements 20, 40 surrounded by openings O (also referred to herein as orifices) which result from the diastolic pressure gradient. Advantageously, leaflets LF are coapted such that their proximal or upstream surfaces face each other in a vertical orientation, parallel to the direction of blood flow through the valve. The upstream surfaces may be brought together so as to be in contactAtty Docket No. ABTEVA-0063PCT with one another or may be held slightly apart but will preferably be maintained in the vertical orientation in which the upstream surfaces face each other at the point of coaptation. This simulates the double orifice geometry of a standard surgical bow-tie repair. Color Doppler echo will show if the regurgitation of the valve has been reduced. If the resulting flow pattern is satisfactory, the leaflets LF may be fixed together in this orientation. If the resulting color Doppler image shows insufficient improvement in valve regurgitation, fixation device 112 may be repositioned. This may be repeated until an optimal result is produced wherein the leaflets LF are held in place.

[0135] FIGS. 4A-19C depict a fixation device 112 according to another embodiment of the present disclosure. Fixation device 112 may generally include a pair of distal elements 120, a pair of proximal elements 140, a coupling member 160, an actuator 113, and a stud 131. Distal elements 120 may include elongate arms 121 in which each arm has a proximal end portion 121a, which may be rotatably connected to the coupling member 160, and a free end 121b, as best shown in FIG. 4A. Free ends 121b may each have a rounded shape to minimize interference with and trauma to surrounding tissue structures according to one example. In one example, each free end 121b defines a curvature extending about two axes 126, 127. The first axis 126 may be a longitudinal axis of each respective arm 121. Additionally, arms 121 may each include an engagement surface 125 that may also be curved about first axis 126 and may extend at least partially along a length of arm 121 to the free end 121b. Thus, in some examples, engagement surfaces 125 may each have a cupped or concave shape which may maximize contact area engagement with tissue and may assist in grasping and holding valve leaflets. Such cupped or concave shape may further allow arms 121 to nest around shaft 111 of interventional tool 110 while in the closed position to minimize the profile of device 112. Thus, arms 121 may be at least partially cupped or curved inwardly about their longitudinal axes 126 which may form a concavity extending along axis 126 which may nest proximal elements 140 when in a lowered position thereof. The second axis 127 about which each free end 121b may be curved may extend perpendicular to first axis 126, as is also shown in FIG. 4A. The curvature about this second axis 127 may be a reverse curvature located at the most distal portion of free ends 121b. In addition to the dual curvature, free ends 121b may flare outwardly at their respective longitudinal edges. It is believed that both the reverse curvature and flare help create an atraumatic configuration that minimizes trauma to the tissue engaged therewith.Atty Docket No. ABTEVA-0063PCT

[0136] In the nonlimiting embodiment depicted, a transverse width across engagement surfaces 125 (which is in the direction of second axis 127 and determines the width of tissue engaged) may be at least about 2 mm, 3-10 mm in some examples, and about 4-6 mm in some examples. Tn some embodiments, a wider engagement may be desired wherein the engagement surfaces 125 are larger, for example about 2 cm, or multiple fixation devices 112 may be used adjacent to each other. Arms 121 may also have a length of about 6-12 mm (defined along first axis 126), and engagement surfaces 125 may be configured to engage a length of tissue of about 4-10 mm along the longitudinal axis 126 of arms 121 according to some examples. Also, as shown in the illustrated example, each arm 121 may include a plurality of openings 128 to enhance grip and to promote tissue ingrowth following implantation.

[0137] In one example, actuator 113 may include two link members or legs 130. Legs 130 may be comprised of a rigid or semi-rigid metal or polymer such as Elgiloy®, cobalt chromium or stainless steel, however any suitable material may be used. Each leg 130 may have a first end 132, which may be rotatably joined with one of the distal elements 120 at a riveted joint 135, and a second end 134, which may be rotatably joined with stud 131, as shown in FIG. 4A. Although the depicted embodiment shows both legs 130 pinned to stud 131 by a single rivet 135, it is also contemplated that each leg 130 may be individually attached to the stud 131 by a separate rivet, pin or the like. In other embodiments of actuator 113, actuator 113 may include a base 139, and second ends 134 of legs 130 may be rotatably joined with base 169, such as by one or more riveted joints 135, as best shown in FIG. 10B. An actuator rod 170 of delivery system 600 may be joinable with actuator 113 directly, such as via direct connection with base 139, or indirectly, such as via connection with stud 131, which itself may extend from base 139. In either of these embodiments, actuator rod 170 may be axially extendable and retractable in a proximal-distal direction to actuate actuator 113 and consequently rotate distal elements 120 between open, closed, and inverted positions, which are described further below. Additionally, coupling member 160, stud 131, and / or base 169 may comprise a center portion or center body of fixation device, for example.

[0138] Proximal elements 140 may, in some examples, be flexible, resilient, and cantilevered from a center of fixation device 112. For example, FIGS. 5 A and 5B depict a gripping device 1 14 according to an embodiment of the present disclosure that may generally include a pair of proximal elements 140, a base section 150, and a pair of arm bend features 153 partitioning proximal elements 140 from base section 150.Atty Docket No. ABTEVA-0063PCT

[0139] Proximal elements 140 may be in the form of elongate bodys 141 that each extend along a longitudinal axis A2 from a first end portion or fixed end 141a to a second end portion or free end 141b, as shown in FIG. 5 A. Each proximal element 140 may also have opposed side edges 142 that define a width transverse to the longitudinal axis A2. Such width may be less than the width of a corresponding distal element 120 such that proximal element 140 may be recessed within the concavity formed by engagement surface 125 of distal element 120 when proximal element 140 is moved into a lowered position, as described in more detail below.

[0140] Proximal elements 140 may also each have a first side or proximal side 143 and a second side or distal side 144. In one example, proximal elements 140 may include a plurality of openings 146 that may extend from proximal side 143 to distal side 144, as shown in FIG. 5 A. Such openings 146 may be used to couple a proximal element line, which is discussed further below, to a proximal element 140 for raising and lowering proximal element 140. Each proximal element 140 may also include one or more frictional elements 145 extending from distal side 144. For example, each proximal element 140 may include one or more rows of frictional elements 145 where frictional elements 145 in each row may be aligned in a direction transverse to longitudinal axis A2. Frictional elements 145 in such rows may also be aligned with frictional elements 145 in other rows in a lengthwise direction thereby forming columns of frictional elements 145. For example, in the embodiment depicted in FIGS. 5 A and 5B, each proximal element 140 may include four rows of two frictional elements 145. In other words, two columns of four frictional elements 145. In other embodiments, proximal elements 140 may include one to six rows of two to six frictional elements 145 per row, for example. However, in other embodiments, frictional elements 145 may be arranged in an offset relationship in a lengthwise and / or transverse direction such that at least some frictional elements 145 are not aligned with another frictional element 145 in such directions.

[0141] Frictional elements 145 may comprise frictional protrusions or tines having tapering pointed tips extending from distal side 144 of proximal elements 140. Frictional elements 145 may also be angled toward fixed end 141a of proximal element 140 which may help prevent frictional elements 145 from inadvertently snaring tissue during repositioning of fixation device 112. In one example, frictional elements 145 may be integral with or connected to a distal surface 144 of a proximal element 140 and protrude therefrom. In another example, as shown in FIG. 5A, frictional elements 145 may be formed from side edges 142, such as byAtty Docket No. ABTEVA-0063PCT cutting and bending the base material forming proximal elements 140, for example. It may be appreciated that any suitable frictional elements may be used, such as prongs, windings, bands, barbs, grooves, channels, bumps, surface roughening, sintering, high-friction pads, coverings, coatings, or a combination of these. However, it should be noted that some types of frictional elements that can be utilized may permanently alter or cause some trauma to the tissue engaged. Thus, it is preferable that frictional elements 145 be atraumatic and generally frictional rather than penetrative so as to not injure or otherwise affect the tissue in a clinically significant way.

[0142] Base section 150 may be connected to a center portion or center body of fixation device 112 such that proximal elements 140 extend outwardly therefrom. For example, base section 150 may be coupled to coupling member 160. In the embodiment depicted, base section 150 may include a first member 152, a second member 154, and a third member 156. First and third members 152, 156 may be connected to second member 154 to form a generally U-shaped or box-shaped structure which may allow a lock (discussed below) to be positioned between first and third members 152, 156. However, other shapes may be formed, such as a V-shape, a crescent shape, or semicircular, for example. In some embodiments, first and third members 152, 156 may be connected to second member 154 via base bend features 157, for example. Also, second member 154 may include an opening 158 extending therethrough for receipt of stud 131 and / or actuator rod 170, as shown in FIG. 5 A.

[0143] Arm bend features 153 may couple a respective proximal element 140 and base section 150. For example, an arm bend feature 153 can couple a proximal element 140 to first member 152 of base section 150, and another arm bend feature 153 can couple the other proximal element 140 to third member 156 of base section 150. As shown, arm bend features 153 may form a living hinge about which proximal elements 140 may bend relative to base section 150. In this regard, arm bend features 153 may be integral with proximal elements 140 and base section 150 and may bias proximal elements 140 to a relaxed position. As illustrated in FIG. 5B, proximal elements 140 may form a relaxed angle 149 formed between proximal sides 143 of each proximal element 140. Such relaxed angle 149 is formed when proximal elements 140 are in the relaxed position and may form an angle of about 85 degrees to 200 degrees (+ / - 5 degrees). For example, proximal elements 140 may fomr a relaxed angle of 180 degrees in the relaxed position. In another example, proximal elements 140 may form a relaxed angle of 185 degrees in the relaxed position. Although the embodiment depicted illustrates bend features 153 as living hinges, in other embodiments bend features 153 may comprise aAtty Docket No. ABTEVA-0063PCT biased hinge that modularly connects proximal elements 140 to base section 150. For example, proximal elements 140 may be separately formed from base section 150 and modularly connected to base section 150 via arm bend features 153 which may each comprise a spring biased hinge biasing a respective proximal element 140 to the relaxed position, for example.

[0144] Arm bend features 153 may also each include an elongate opening extending 151 along the longitudinal axis A2 which may furcate each arm bend feature 153, as illustrated in FIG. 5 A. Such an elongated opening 151 may have a uniform width extending along axis A2. However, in some embodiments, such as the embodiment depicted, elongate opening 151 may form a bowling-pin shape such that a width of opening 151 is narrower at one end (e.g., the end closest to free end 141b) than the other end (e.g., the end furthers from free end 141b) and is wider somewhere in between. Elongate opening 151 may also not be relegated to just arm bend feature 153 but may also extend from arm bend feature 153 to proximal element 140 and / or base body 150. The elongate opening 151 and corresponding furcation of arm bend features 153 may be configured (e.g., in size, shape, spacing, position, etc.) so as to provide the desired resiliency, fatigue resistance, and / or flexibility at the coinciding arm bend features 153.

[0145] Base bend features 157 and arm bend features 153 may be configured to give gripping device 1 16 a bent configuration when gripping device is in a relaxed state (z.e., when proximal elements are in the relaxed position), such that when gripping device 114 is forced into a stressed state (e.g., by bending proximal elements at one or more of the base and / or arm bend features 112). In the exemplary embodiment depicted, gripping device 114 may be formed from a metallic sheet of a spring-like material, such as a shape-memory metal (e.g., Nitinol) which may provide the bias of proximal elements 140 toward the relaxed position. Alternatively, gripping device 114 could be molded from a biocompatible polymer. Each proximal element 112 may, in one example, be configured to be at least partially recessed within the concavity of the distal element 120 when no tissue is present. When fixation device 112 is in the open position, each proximal element 140 may be separated from the engagement surface 125 near free end 121b of arm 121 and may slope toward engagement surface 125 near free end 121b with the free end 141b of proximal element 140 contacting engagement surface 125, as illustrated in FIGS. 4A and 1 IB. This arrangement may be facilitated by the dimensions of base section 150. For example, increasing or decreasing the respective lengths of first, second, and third members 152, 154, 156 of base section 150 may increase or decrease the separation distance between a proximal element 140 and corresponding distal element 120Atty Docket No. ABTEVA-0063PCT which may help accommodate a valve leaflet or other tissues of varying thicknesses. Further examples of gripping devices that may be utilized in fixation device 112 are described in more detail in U.S. Patent No. 11,096,691, the disclosure of which is incorporated by reference herein in its entirety.

[0146] In other embodiments proximal elements may be connected to or otherwise extend from distal elements rather than from a center of fixation device, like that of fixation device 112. For example, FIGS. 6A and 6B depict a gripping device 214 according to another embodiment of the present disclosure that may generally include a first arm 240, a second arm 250, and an arm bend feature 260 partitioning first arm 240 from second arm 250. Gripping device 214 may be made from a shape-memory-metal material, such as Nitinol, for example.

[0147] First arm 240 may constitute a proximal element of fixation device 112, like that of and as an alternative to proximal element 140 and may include one or more frictional elements 245 which may be similar to frictional elements 145 discussed above. Thus, a plurality of frictional elements 245 may extend from a distal side of first arm 240 such as in one or more rows and / or columns. In the embodiment depicted, a single row of three frictional elements 245 may be provided near a free end 241b of first arm 240. But, as mentioned above, first arm 240 may have any number of frictional elements 245, such as two, four, or six, for example. First arm 240 may also include a pair of elongate members 247 offset from each other to form a space 248 therebetween. Such space 248 may be configured to receive second arm 250, for example. Additionally, first arm 240 may include one or more openings 246, such as near free end 241b, as shown in FIG. 6A. Such opening 246 may be configured to receive a proximal element line for raising and lowering first arm 240.

[0148] Second arm 250 may be in the form of a beam or other elongate structure. Second arm 250 (also referred to herein as base section) may be configured to couple to a distal element 120. For example, in the embodiment depicted in FIGS. 6A and 6B, second arm 250 may be curved in a plane transverse to its longitudinal axis. For example, second arm 250 may be semi-cylindrical such that it may have a semi-circular profile. Thus, second arm 250 may have a convex surface 255 configured to conform to the cupped curvature of engagement surface 125 of a corresponding distal element 120. FIG. 6B illustrates second arm 250 coupled to proximal engagement surface 125 of distal element 120 such that it is generally recessed within distal element 120 and free ends 241b, 251b of first and second arms 240, 250 point in the general direction toward free end 121b of distal element 120. Thus, in some embodiments,Atty Docket No. ABTEVA-0063PCT second arm 250 may have a width configured to be positioned within the concavity of distal element 120 and secure to proximal engagement surface 125. In other embodiments, a second arm 250’ of an alternative gripping device 214’ may not be concave and may instead have a planar surface corresponding to a planar engagement surface 125’ of an alternative distal element 120’ and secured thereto, as illustrated in FIG. 6C. In further embodiments, distal element 120 may include a recess or pocket for receipt and securement of second arm 250, such as in a press-fit manner, for example. Second arm 250 may be secured to distal element 120 in any number of ways, such as via one or more sutures, welding, press-fit, fastener (e.g., rivet or screw) or the like. For example, a rivet, screw, or suture may pass through one or more openings 257 in second arm 250 and into distal element 120. A tissue fixation device, such tissue fixation device 112, may include a pair of gripping devices 214 with one coupled to each distal element 120 as mentioned above.

[0149] Arm bend feature 260 may be coupled to a fixed end 241 of first arm 240 and a fixed end 251a of second arm 250 such that first and second arms 240, 250 extend in the same general direction and may form a V-shape when first arm 240 is in an exemplary open or raised position, as illustrated in FIGS. 6B and 6C. As shown, arm bend feature 260 may form a living hinge about which first arm 240 may bend relative to second arm 250. In this regard, arm bend feature 260 may be integral with first arm 240 and second arm 250 so as to form a monolithic structure and may bias first arm 240 to a relaxed position. Such relaxed position may include second arm 250 extending through space 248 between elongate members 247 of first arm 240 to form an X-shape. However, it should be noted that such position can generally only be achieved when gripping device 214 is not coupled to distal element 120 as the presence of distal element 120 would prevent second arm 250 from passing into space 248. It should also be appreciated that in some embodiments of gripping device 214, arm bend feature 260 may be a spring loaded or otherwise biased hinge coupling separately formed first and second arms 240, 250.

[0150] Fixation device 114 may also have a covering 117, as shown in FIG. 4B. As depicted, covering 117 may encapsulate distal elements 120 and actuator 113. Thus, engagement surfaces 125 may be covered by covering 117 which may help minimize trauma on tissues and enhance primary fixation via additional friction to assist in grasping. Additionally, covering 117 on engagement surfaces 125 may facilitate tissue ingrowth to provide for secondary fixation to ensure long-term security. Covering 117 may be loosely fittedAtty Docket No. ABTEVA-0063PCT and / or may be flexible such that device 112 can freely move to various positions all the while covering 117 conforms to the contours of the device 112 and remains securely attached thereto. It may be appreciated that the covering 117 may cover specific parts of fixation device 112 while leaving other parts exposed. For example, proximal elements 140 may be exposed, while distal elements 120 and actuator 113 may be covered. However, in some embodiments, proximal elements 140 may be covered with covering 117 to enhance grip and tissue ingrowth following implantation. Preferably, when a covering 117 is used in combination with frictional elements 145 or other frictional features, such as those extending from proximal elements 140, such features may protrude through such covering 117 so as to contact any tissue engaged by proximal elements 140.

[0151] Covering 117 may be comprised of any biocompatible material, such as polyethylene terepthalate, polyester, cotton, polyurethane, expanded polytetrafluoroethylene (ePTFE), silicon, or various polymers or fibers and have any suitable form, such as a fabric (woven or unwoven), mesh, textured weave, felt, looped or porous structure. Generally, covering 117 has a low profile so as not to interfere with delivery through an introducer sheath or with grasping and coapting of leaflets or tissue. Covering 117 may alternatively be comprised of a polymer or other suitable materials dipped, sprayed, coated, or otherwise adhered to the surfaces of the fixation device 112. Optionally, a polymer coating may include pores or contours to assist in grasping the tissue and / or to promote tissue ingrowth. Any of the coverings 117 may optionally include drugs, antibiotics, anti -thrombosis agents, or anti-platelet agents such as heparin, COUMADIN® (Warfarin Sodium), to name a few. These agents may, for example, be impregnated in or coated on the coverings 117. These agents may then be delivered to the grasped tissues surrounding tissues and / or bloodstream for therapeutic effects.

[0152] FIGS. 7A-7C depict an exemplary coupling system 115 between fixation device 112 and delivery system shaft 111. As mentioned above, once the leaflets of a target valve are coapted in the desired arrangement, fixation device 112 may then be detached from delivery system 600 and left behind as an implant to hold the leaflets together in the coapted position. Such detachment may occur between coupling member 160 of fixation device 112 and a distal end of delivery shaft 111. Thus, coupling member 160 may be configured to be releasably coupled to shaft 1 11. Coupling member 160 may be disposed at a center of fixation device 112 and may extend proximally along it’s the longitudinal axis of fixation device 112. In the coupling system 115 depicted, shaft 111 may form a tubular upper shaft with a first matingAtty Docket No. ABTEVA-0063PCT surface 163 formed at a distal end thereof, and coupling member 160 may form a detachable lower tubular shaft with a second mating surface 162 formed at a proximal end thereof. Mating surfaces 162, 163 may be correspondingly shaped so that they interlock and form a joining line 165 when merged together, as shown in FIG. 7B. In this regard, mating surfaces 162, 163 may have any shape or curvature which allows or facilitates interlocking and later detachment. For example, in the depicted embodiment, mating surfaces 162, 163 define a joining line 165 with an S-shaped curvature.

[0153] Coupling system 115 may also include actuator rod 170 and stud 131 (or alternatively base 139) such that fixation device 112 may also be releasably coupled to delivery system 600 via connection between actuator rod 170 and stud 131. When shaft 111 is coupled to coupling member 160, they may collectively form an axial channel. Actuator rod 170 may pass through this channel to bridge the joining line 165, as shown in FIG. 7B. Actuator rod 170 may comprise a proximal extremity 171, a distal extremity 172, and a joiner 174. Distal extremity 172 may be smaller in diameter than proximal extremity 171 and may be optionally surrounded by a coil 173 which may serve to bias joiner 174 in a proximal direction. However, in some embodiments, actuator rod 170 may not have coil 173 or proximal and distal extremities 171 , 172 of differing diameters. Joiner 174 may be removably coupled with stud 131 of fixation device 112 via any one of various possible release mechanisms. For example, in the embodiment depicted, joiner 174 may be threadedly connected to stud 131 of fixation device 112. In this regard, joiner 174 may have internal threads 175 which mate with external threads 133 on stud 131. Alternatively, joiner 174 may have external threads which mate with internal threads of stud 131. As described previously, stud 131 may be connected with distal elements 120 so that advancement and retraction of stud 131, by means of actuator rod 170, manipulates distal elements 120. It is also contemplated that joiner 174 may be directly threadedly engaged with base 139 where no stud 131 is provided. Once detachment of fixation device 112 is desired, actuator rod 170 may be rotated until threads 175 of joiner 174 disengage threads 133 of stud 131. Actuator rod 170 may then be retracted to a position above mating surfaces 162, 163 which in turn allows coupling member 160 to separate from shaft 111 along joining line 165, as illustrated in FIG. 7C.

[0154] FIGS. 8A and 8B illustrate an alternative example of a coupling system. In this exemplary coupling system 315, shaft 311 of the delivery system (e.g., delivery system 600) may be releasably coupled with coupling member 360 via a detent mechanism, for example. InAtty Docket No. ABTEVA-0063PCT this regard, shaft 311 may form an upper tubular shaft with detent mechanism features and coupling member 360 may form a lower tubular shaft with detent mechanism features configured to releasably connect with the detent mechanism features of shaft 311. In the embodiment depicted, the detent mechanism may include one or more spring arms 361 integrally formed on shaft 311 and one or more receptacles 362 sized to receive spring arms 361 within coupling member 360. However, shaft 311 may include receptacles 362, while coupling member 360 may include spring arms 361, for example. As shown, spring arms 361 may have a flange-like engagement element 363 at a distal end thereof and are preferably biased inwardly, i.e., toward an interior shaft 311, as shown in FIG. 8B. Receptacles or apertures 362 may be configured to receive and mate with respective engagement elements 363 of spring arms 361, as shown in FIG. 8 A. Receptacles 362 may extend all the way through the wall of coupling member 360 and may be sized to snuggly fit both engagement elements 362. A snuggly fitting rod (such as actuator rod 370) may extend through shaft 311 and coupling member 360 and may outwardly deflecting the inwardly biased spring arm(s) 361 such that the engagement elements 363 are pushed into respective engagement with a corresponding receptacle 362 thereby coupling the shaft 311 to coupling member 360, as shown in the example of FIG. 8A. When desirable to detach fixation device 1 12 from delivery system 600, actuator rod 370 may be retracted to a position above spring ami(s) 361 and engagement features 363 thereof. This allows the inwardly biased spring arms 361 and corresponding engagement elements 363 to disengage from receptacles 362 thereby detaching shaft 31 1 and coupling member 360. As mentioned above, actuator rod 370 may be threadedly engaged to stud 131. Thus, actuator rod 370 may first be rotated to unthread its threads 375 from stud 131 and then retracted to release coupling member 360 according to an example of the disclosure.

[0155] As mentioned above, fixation device 112 may, in one example, be actuated through multiple positions within a mammalian body during a transcatheter procedure such as by extending and retracting actuator rod 170 when coupled to stud 131 and / or base 139. FIGS. 9A-9B, 10A-10B, 11A-1 IB, 12A-12B, and FIGS. 13A-13B illustrate several of these possible positions and in a sequence that may be utilized during a transcatheter procedure.

[0156] FIGS. A and 9B depict fixation device 112 in an example of a closed position or delivery position. Fixation device 112 may assume the closed position when being delivered through a guide catheter or sheath 3300 of steerable guide system 5, as shown in FIG. 9A. InAtty Docket No. ABTEVA-0063PCT the closed position, the opposed pair of distal elements 120 may be positioned so that engagement surfaces 125 thereof face each other. The cupped or concave shape of each ami 121 in this example allows arms 121 to surround shaft 111 and optionally contact each other on opposite sides of shaft 1 11. This provides a low profile for fixation device 1 12 so that it is readily passable through a delivery catheter 3300 and through any anatomical structures, such as those within the cardiovascular system.

[0157] FIGS. 10A-10B depict fixation device 112 in an example of an open position. Fixation device 112 may assume the open position for capturing and grasping leaflets of a heart valve. In an open position, distal elements 120 may be rotated so that engagement surfaces 125 thereof face a first direction such that engagement surfaces 125 are disposed at an acute angle relative to shaft 111. For example, the acute angle formed between each engagement surface 125 and shaft may be 45 degrees to 90 degrees. Stated differently, in the open position, engagement surfaces 125 of distal elements 120 may be oriented 90 degrees to 180 degrees relative to each other. However, it is generally preferable for arms to be positioned 120 degrees relative to each other (and 60 degrees relative to shaft 111) for capturing leaflets. Movement of fixation device 112 from the closed position to the open position may be achieved by advancing stud 131 distally relative to coupling member 160 by distally advancing actuator rod 170. Conversely, fixation device 112 may be moved from the open position to the closed position by retracting actuator rod 170 and retracting stud 131 proximally, according to one example of the disclosure.

[0158] As shown in FIG. 10B, proximal elements 140 (or proximal elements 240) may be in a raised or insertion position when fixation device 112 is in the open position to facilitate insertion of leaflets between distal and proximal elements 120, 140 for their capture. Proximal elements 140 are, in one example, biased toward distal elements 120. In this regard, proximal elements 140 may be moved inwardly toward shaft 111 and held against shaft 111 with the aid of proximal element lines 101 which can be in the form of sutures, wires, nitinol wire, rods, cables, polymeric lines, or other suitable structures, as shown in FIG. 10A. Thus, FIGS. 10A and 10B depict fixation device 112 in an insertion configuration in which proximal elements 140 are in a raised position and distal elements 120 are in an open position.

[0159] Once fixation device 112 has been positioned in a desired location against the valve leaflets, the leaflets may then be captured between proximal elements 140 and distal elements 120. FIGS. 11A and 11B illustrate fixation device 112 in an example of such aAtty Docket No. ABTEVA-0063PCT position. Here, proximal elements 140 are lowered toward engagement surfaces 125 so that proximal elements 140 are in a lowered or capture position, and the leaflets are held between distal and proximal elements 120, 140. Proximal elements 140 are, in one example, lowered into the lowered position while distal elements 120 remain in the open position. Thus, fixation device 112, as shown in FIGS. 11 A and 1 IB is in an example of a capture configuration which may be similar to the insertion configuration of FIGS. 10A and 10B, but with the difference being that proximal elements 140 are now lowered toward distal elements 120 by releasing tension on proximal element lines 101 to compress the leaflet tissue therebetween. At any time, the proximal elements 140 may be raised and the distal elements 120 adjusted or inverted to reposition fixation device 112 if regurgitation is not sufficiently reduced according to one example of the disclosure.

[0160] FIGS. 12A-12B depict an example of an inverted position of fixation device 112. Fixation device 112 may assume the inverted position to aid in repositioning or removal of fixation device 112. In one example of the inverted position, distal elements 120 may be further rotated from the open position, which may be achieved by advancing stud 131 further relative to the open position, so that the engagement surfaces 125 of distal elements 120 face outwardly, and free ends 121b point distally. Additionally, in some examples, engagement surfaces 125 of each arm 121 may form an obtuse angle relative to shaft 111. For example, the obtuse angle formed between each engagement surface 125 and shaft 111 may be 135 degrees to 180 degrees. Stated differently, in the inverted position, engagement surfaces 125 of distal elements 120 may be oriented 270 degrees to 360 degrees relative to each other.

[0161] Also, as shown in FIG. 12B, in one example proximal elements 140 are in their raised position against shaft 111 while distal elements 120 are in the inverted position by exerting tension on the proximal element lines 101. Thus, a relatively large space may be created between proximal and distal elements 140, 18 for repositioning. In addition, the inverted position allows withdrawal of the fixation device 112 through the valve while minimizing trauma to the leaflets. Engagement surfaces 125 provide an atraumatic surface for deflecting tissue as the fixation device is retracted proximally. It should be further noted that tines 145 of proximal elements 140 may, in some examples, be angled slightly in the distal direction (away from the free ends of the proximal elements 140), reducing the risk that tines 145 will catch on or lacerate tissue as fixation device 112 is withdrawn and while proximal elements 140 are in the raised position.Atty Docket No. ABTEVA-0063PCT

[0162] After the leaflets have been captured between distal and proximal elements 120,140, distal elements 120 may be relumed to or toward the closed position where they may be locked in place. An example of such locking is described further below. FIG. 13A illustrates fixation device 112 in the closed position wherein the leaflets (not shown) are captured and coapted. In one example, this is achieved by retraction of the stud 131 proximally relative to coupling member 160 so that the legs 130 of the actuator 113 apply an upwards force to distal elements 120 which in turn rotate distal elements 120 so that engagement surfaces 125 again face one another, similar to that of FIGS. 9 A and 9B, and so that distal elements 120 rotate proximal elements 140 in a direction toward shaft 111. However, because the leaflets are captured between distal and proximal elements 120, 140, it may be desirable to keep distal elements 120 at about 20 degrees to 60 degrees relative to each other so as to limit the amount of tension and stress on the native tissue. Thus, while fixation device 112 may be returned to the closed position, such closed position may not be as closed as in the initial delivery position.

[0163] As shown in FIG. 13B, fixation device 112 may then be released from shaft 111 of delivery system 600 while in the closed position. As mentioned, fixation device 112 may be releasably coupled to delivery system 600 via a coupling system (e.g., coupling system 115 or 315). When the coupling structures of such coupling system are released, proximal element lines 101 may remain attached to proximal elements 140 following detachment to function as a tether to keep the fixation device 112 connected with the delivery catheter 610 (see FIG. 16) for reconnection and repositioning. However, in other embodiments, proximal elements lines 101 may be released prior to release of fixation device 1 12 or concurrently with the release of fixation device 112, as described in more detail below.

[0164] FIG. 13C illustrates a released fixation device 112 in an example of a closed position. As shown, coupling member 160 remains separated from shaft 111 of delivery system 600, and proximal elements 140 are deployed so that tissue (not shown) may reside between proximal elements 140 and distal elements 120.

[0165] As mentioned above, proximal element lines or actuators 101 may be releasably coupled to proximal elements 140. In some examples, proximal element lines 101 may pass through an opening in proximal elements 140, such as openings 146 and 246 in the case of proximal element 240. In other examples, eyelets, which may be formed from one or more lengths of suture, may be coupled to proximal elements 140 and proximal element lines 101 may pass through such eyelets. Thus, proximal element lines 101 may be released fromAtty Docket No. ABTEVA-0063PCT proximal elements 140 prior to, concurrent with, or after release of fixation device 112 from delivery system 600 according to various examples.

[0166] In an exemplary embodiment of interventional tool 110, as shown in FIG. 14, a plurality of proximal element lines 101 a, 101b may extend through corresponding lumens 614a, 614b of shaft 111 of delivery system 600 (see FIG. 16) and may be coupled to proximal elements 140 of fixation device 112. Each of proximal element lines 101a and 101b may be elongated flexible threads, wire, cable, sutures, or lines extending through shaft 111, looped through proximal elements 140, and extending back through shaft 111 to a delivery device handle of delivery system 600. When detachment is desired, one end of each proximal element line 101a, 101b may be released from delivery system 600, and the other end pulled to draw the free end distally through shaft 111 and through proximal element 140 thereby releasing it. Also, in this arrangement, proximal element lines 101a and 101b may be independently or concurrently manipulated so as to independently or concurrently raise and lower proximal elements 140, respectively.

[0167] In another example, interventional tool 110' may be configured, as shown in FIG. 15 with respect to certain components thereof, such that proximal elements 140 may alternatively be supported by a single proximal element line 101 which may extend through both of the proximal elements 140. In this arrangement both proximal elements 140 may be raised and lowered concurrently by action of a single proximal element line 101. Whether proximal elements 140 are manipulated individually by separate proximal element lines 101 or jointly by a single proximal element line 101, the proximal element lines 101 may extend directly through openings (e.g., openings 146, 246) of the proximal elements 140 and / or through a layer or portion of a covering 117 on proximal elements 140, or through a suture loop / eyelet above or below a covering 117, for example.

[0168] In a further example, interventional tool 110” may be configured, as shown in FIG. 16, such that each proximal element line 101a, 101b may be releasably engaged with structures that are activated by removal of the actuator rod 170 that passes through coupling member 160 and shaft 111 such that release of proximal element lines 101a, 101b occurs concurrently with the release of fixation device 112 from delivery system 600. Thus, in one example, which is depicted in FIG. 16, each proximal element line 101a, 101b may have a first end portion 103a (e.g. , proximal end portion), which may be coupled to an actuator of a delivery system handle, a second end portion 103b e.g., distal end portion) which may be releasablyAtty Docket No. ABTEVA-0063PCT engages to shaft 111 via actuator rod 170, and an intermediate portion 103c which may be coupled to a proximal element 140. As described above and as illustrated in FIG. 7A, stud 131 may be releasably attached to actuator rod 170 which passes through coupling member 160 and shaft 11 1 of delivery system 600. In this way, actuator rod 170 is connectable with fixation device 112 and acts to manipulate fixation device 112 so as to move it through its various positions, which are described above. After the leaflets have been coapted, actuator rod 170 may be removed proximally from stud 131 which may thereby also release coupling member 160 from shaft 111, as described with respect to FIGS. 7A-7C and also FIGS. 8A and 8B with respect to coupling system 315. This action of actuator rod 170 may be utilized to release distal end portion 103b of each of proximal element lines 101a, 101b.

[0169] Exemplary features which may be implemented in interventional tool 110” to facilitate release of proximal element lines 101a, 101b in this manner are shown in FIGS. 17A- 17G. As depicted, an actuator rod 470 may be used as an anchor to restrict proximal movement of one or more proximal element lines 401. Proximal element line 401 has a distal end portion 403b which may include a catch element 405 (or catch), for example a trumpet 405 having a cone shape (see FIG. 17D) or other shapes, such as a ball 405’ having a spherical shape (see FIG. 17G), which can be sized to be received within shaft 411. As shown in the example of FIGS. 17B, shaft 411 may have spring arms 461 like that of the coupling system 315 of FIGS. 8A and 8B for releasing device 112 from shaft 411. However, shaft 411 may also have mating surfaces of FIGS. 7A and 7C. In any event, a portion of shaft 411 proximal of spring arms 461 (or mating elements 463), may have two slots 412a and 412b defined therein. Slot 412a can define holes 414a and 414b and slot 412b can define holes 414c and 414d. Holes 414a and 414c can be sized to receive catch element 405 of a pair of proximal element lines 401, respectively, therethrough and into slots 412a and 412b, respectively. Holes 414b and 414d can be sized to prevent catch element 405 of proximal element lines 401, respectively, from extending beyond slots 412a and 412b, respectively. The configuration of slots 412a and 412b and holes 414a-414d can allow for easier manufacture of the features in shaft 411. Slots 412a and 412b can be drilled to ensure that slots 412a and 412b do not pass the entire way through shaft 411. In this example configuration, catch elements 405 of proximal element lines 401 can be maintained within shaft 411 to manage the slack of proximal element lines 401.

[0170] In one example, catch element 405 of proximal element line 401 can be inserted into slot 412a through hole 414a beyond a longitudinal axis of shaft 411 and toward hole 414b,Atty Docket No. ABTEVA-0063PCT and catch element 405 of proximal element line 401 can be inserted into slot 412b through hole 414c beyond the longitudinal axis of shaft 411 and toward hole 414d prior to the insertion and coupling of the actuator rod 470 (which passes through shaft 411) with stud 131 of fixation device 1 12. With actuator rod 470 extending through shaft 41 1 , actuator rod 470 may directly engage catch elements 405 of lines a plurality of proximal element lines 401 thereby preventing their movement back out along the path through which they were inserted. For example, trumpets 405 can be inhibited from being advanced through holes 414b and 414d, respectively, and can be prevented from being pulled past actuator rod 470 and through holes 414a and 414c, respectively. Accordingly, the second end portions 403b of proximal element lines 401 can be held in place relative to shaft 414. Once the actuator rod 470 is decoupled from stud 131 and subsequently retracted, movement of catch elements 405 at the distal end portions of proximal element lines 401 is no longer restricted and proximal element lines 401 are free to move. Upon proximal retraction, proximal element lines 401 can thread through holes 414a and 414c, respectively, and decouple from the proximal elements 140.

[0171] In accordance with one example of the disclosed subject matter, slots 412a and 412b can be drilled at an angle towards the distal end of shaft 411 (see FIGS. 17E and 17F), e.g., with hole 414b formed distal to hole 414a on one side, and hole 414d formed distal to hole 414c on the other side. This example configuration of slots 412a and 412b can provide easier deployment of a plurality of proximal element lines 401 and can reduce friction.

[0172] Prior to securing second end portion 403b of each proximal element line 401 with the shaft 411, each proximal element line 401 can be coupled with a respective proximal element 140, such as in the manner described above with respect to FIG. 16. Thus, when proximal element lines 401 are actuated proximally, proximal element lines 401 can move proximal elements 140 relative to distal elements 120, thereby moving proximal elements 140 between their respective raised and lowered positions.

[0173] As mentioned above, fixation device 112 optionally includes a lock e.g., lock 116) for locking device 112 in a particular position, such as in any one of the aforementioned open, closed, and inverted positions or any position therebetween. It may be appreciated that according to various examples, lock 116 may be configured for both locking and unlocking which correspondingly allows device 112 to be both locked and unlocked. As described in more detail below with respect to various lock examples, such locks may have components disposed between coupling member 160 and base 139 which may be configured to selectivelyAtty Docket No. ABTEVA-0063PCT arrest proximal-distal movement of stud 131 / base 139 which consequently arrests movement of distal elements 120. Such locks may help provide end user control of the final arm angle of fixation device 112 for tailored and optimal results for each patient. Additionally, such locks may bring the leaflets and annulus together which may result in beneficial dimensional changes of the target valve which can prevent adverse remodeling of the heart, particularly for patients with heart failure.

[0174] FIGS. 14, 15, and 16A- 16C illustrate an embodiment of the lock 116. Lock 116 generally includes a housing 181, one or more wedging elements 180, a release harness 190, and a biasing member 189. Housing 181 may be positioned distal to coupling member 160 and may be free-floating, coupled to, or integral with coupling member 160, such as at a distal end thereof. Housing 181 may form a window 183 which may be defined at opposite sides with sloping or tapered surfaces 185 which slope inwardly toward stud 131 in a proximal to distal direction. Wedging elements 180 may be in the form of rolling elements, such as a pair of barbells, disposed on opposite sides of stud 131 and between sloping surfaces 185, as shown in FIGS. 18A and 18B. Each barbell 180 may have a pair of generally cylindrical caps 182 and a shaft 184 therebetween, as illustrated in the barbell cross-section of FIG. 16A. Barbells 180 and stud 131 are preferably comprised of cobalt chromium or stainless steel, however any suitable material may be used. Biasing member 189 may be a spring, such as a leaf spring, for example, and may be positioned at a proximal end of housing 181 between sloping surfaces 185 and proximal to barbells 180 such that spring 189 bears on barbells 180 and biases them in a distal direction. Thus, when barbells 180 are pushed distally by spring 189, they are correspondingly pushed inwardly and wedged against stud 131 by sloping surfaces 185, as illustrated by FIG. 18 A, which depicts barbells 180 in a proximal and unlocked position, and FIG. 18B, which depicts barbells 180 in a distal and locked position.

[0175] As shown in FIGS. 14, 15, and 18C, release harness 190 may be in the form of a ridged wire or rod that may extend proximally from stud 131 toward a proximal end of fixation device 112 and at opposite sides thereof. In this regard, release harness 190 may form a first portion or front portion 192a and a second portion or rear portion 192b. Each of first and second portions 192a, 192b may include a crest or closed proximal end 194 through which a lock line 102 may be threaded and engaged, as described below. Release harness 190 may also form hooked distal ends 196a, 196b which may extend between first and second portions 192a, 192b and between sloping surfaces 185 and stud 131, as shown in FIGS. 18A and 18B. Thus,Atty Docket No. ABTEVA-0063PCT hooked ends 196a and 196b may be moveable proximally-distally within window 183 formed between sloped surfaces 185 and stud 131. Additionally, hooked ends 196a and 196b may be positioned distal of barbells 180 such that pulling up on harness 190 moves hooked ends 196a, 196b proximally so as to push the respective barbells 180 against the bias of spring 189 and move them to their unlocked position.

[0176] Movement of harness 190 may be performed by one or more lock line 102 which may be coupled to harness 190 by such as by threading lock line 102 through and engaging one or more of proximal ends 194 of first and second portions 192a, 192b thereof, as shown in FIGS. 14 and 15. Such lock line 102 may have a first end 102a fixedly secured to a delivery system handle of delivery system 600 and a second end 102b releasably secured to a delivery system handle, as described in more detail below. In this regard, tension can be selectively applied to lock line 102 to unlock and lock the lock 116. Also, lock line 102 can be released from release harness 190 prior to, concurrently with, or after release of fixation device 112 from delivery system 600 which may be achieved by releasing the second end 102b from delivery system handle and pulling lock line 102 and its second end through shaft 111. Lock line 102 may be comprised of any suitable material, typically wire, nitinol wire, cable, suture, or thread, to name a few. In addition, lock line 102 may include a coating, such as parylene. Parylene is a vapor deposited pinhole free protective film which is conformal and biocompatible. It is inert and protects against moisture, chemicals, and electrical charge.

[0177] When an upwards force is applied to harness 190 by the lock line 102, hooked ends 196a, 196b may raise barbells 180 against spring 189, as shown in FIG. 18A. This may draw barbells 180 up along sloping surface 185 which un wedges barbells 180 from against stud 131. In this position, stud 131 is free to move. Thus, when lock line 102 is tensioned to raise or lift harness 190, lock 116 is in an unlocked position wherein stud 131 is free to move actuator 113 and therefore distal elements 120 to any desired position. Releasing tension in lock line 102 may, on the other hand, transition the lock 116 to a locked position, as shown in FIG. 18B. Thus, by releasing the upwards force on barbells 180 by hooked ends 192a, 192b, spring 189 forces barbells 180 downwards and wedges barbells 180 between a sloping surface 185 and stud 131. This restricts motion of stud 131, which in turn locks actuator 113 and therefore distal elements 120 in place. In addition, stud 131 may include one or more grooves or indentations 137 which may receive shaft 184 of each barbell 180. This may provide more rapid and positive locking by causing barbells 180 to settle in a definite position, increase the stability of lock 116Atty Docket No. ABTEVA-0063PCT by further preventing movement of barbells 180, as well as tangible indication to the user that each barbell 180 has reached a locking position. In addition, grooves 137 may be used to indicate the relative position of distal elements 120, particularly the distance between distal elements 120. For example, each groove 137 may be positioned to correspond with a 0.5- or 1.0-mm decrease in distance between distal elements 120. As stud 131 is moved, barbells 180 may contact grooves 137, and by counting the number of grooves 137 that are felt as stud 131 is moved, the user can determine the distance between distal elements 120 and can provide the desired degree of coaptation based upon leaflet thickness, geometry, spacing, blood flow dynamics and other factors. Thus, grooves 137 may provide tactile feedback to the user.

[0178] Lock 116 allows fixation device 112 to remain in an unlocked position when attached to delivery system 600 during grasping and repositioning and then maintain a locked position when left behind as an implant. It may be appreciated, however, that lock 116 may be repeatedly locked and unlocked throughout the placement of the fixation device 112 if desired. Once the final placement is determined, lock line 102 may be removed and fixation device 112 may be left behind.

[0179] FIGS. 19A-19C depict a lock 516 according to another embodiment of the present disclosure that may be incorporated into a fixation device 112 of the disclosure. In this embodiment, lock 516 also includes a housing 581, a spring 589, a release harness 590, and a wedging element 500. However, instead of sloping surfaces 185 as present in the example of locking element 116, housing 185 may include generally parallel sidewalls 585 and may include a finger or protrusion 587 extending from one of sidewalls 585 toward stud 131, as best shown in FIG. 19C. Such finger 587 may slope in a distal direction and may define a proximal notch 588. Also, as shown in FIG. 19C, first hooked end 596a of release harness 590 may be positioned distal of finger 587.

[0180] Furthermore, wedging element may comprise a binding lever or binding plate 500. As shown in FIG. 19B, binding plate 500 may have an oblong shape that may extend lengthwise between a first end 501 and a second end 502 thereof. An aperture 504 may be formed between first and second ends 501, 502 and may extend from a top planar surface 508 through a bottom planar surface 506 of binding plate 500. Binding plate 500 may be positioned between sidewalls 406 so that stud 131 passes through aperture 504 and so that first end 501 of binding plate 500 is positioned within notch 588 proximal of finger 587, as best shown in FIG. 19C. Thus, finger 587 may be positioned between first end 501 of binding plate 500 andAtty Docket No. ABTEVA-0063PCT first hooked end 596a of released harness 590. Also, spring 589 may be positioned proximal to binding plate 500 and provide downward or distal bias thereto. Binding plate 500 and stud 131 may be comprised of any suitable material. In some embodiments, binding plate 500 may have a higher hardness than stud 131. In other embodiments, binding plate 500 may be comprised of a flexible or semi-flexible material. Such flexibility may allow slight movement of stud 131 in the proximal and distal directions, therefore allowing slight movement of distal elements 120 when lock 516 is in the locked position. This may allow fixation device 112 to adjust in response to dynamic cardiac forces.

[0181] FIGS. 19A and 19C illustrate binding plate 500 in a locked position or configuration. In this regard, spring 589 pushes binding plate 500 in a distal direction. However, because first end 501 of binding plate 501 is positioned within notch 588, axial movement of first end 501 toward a distal end of housing 581 is prohibited while axial movement of second end 502 of binding plate 500 is permitted. Thus, finger 587 obstructs first end 501 from axial movement and creates a lever type movement of binding plate 500. Moreover, finger 587 obstructs first hooked end 596a of release harness 590 from axial movement resulting in a side-to-side pivoting of release harness 590 upon tension of lock line 102. This pivoting movement correspondingly results in second hooked end 596b of release harness moving proximally and controlling movement of second end 502 of binding plate 500. As such, when an upwards force is applied to harness 590 by lock line 102, second hooked end 596b of release harness 590 raises second end 502 of plate 500 against spring 589 so that planar surfaces 506, 508 of binding plate 500 become oriented substantially perpendicular to stud 131. This aligns aperture 504 with stud 131 allowing free movement of stud 131 in the proximal- distal direction. Thus, in this state, lock 516 is unlocked wherein stud 131 is free to move actuator 113 and therefore distal elements 120 to any desired position.

[0182] Release of harness 590 by lock line 102 transitions lock 516 back to the locked position. By releasing the upwards force on second end 502 of binding plate 500, spring 589 forces second end 502 of biding plate 500 downwards, which misaligns aperture 504 relative to stud 531, and correspondingly wedges binding plate 500 against stud 131, as best shown in FIG. 19C. This arrests movement of stud 131, which in turn locks actuator 113 and therefore distal elements 120 in place. It may be appreciated that binding plate 500 may have any suitable form to function as described above. For example, plate 500 may have a variety of shapes with or without planar surfaces 506, 508 and / or the aperture 504 may be of a variety of shapes andAtty Docket No. ABTEVA-0063PCT positioned in a variety of locations, to name a few. For example, binding plate 500 may not have a through-hole, like that of aperture 504, but may rather have a notch such that binding plate 500 does not encircle stud 131 but rather partially surrounds it. Further, it may be appreciated that any number of binding plates 500 may be present. Fach binding plate 500, in this regard, may provide an additional binding location which may enhance lock performance.

[0183] While the above-described nonlimiting examples of fixation device 112 may utilize a push-to-open, pull-to-close mechanism for opening and closing distal elements 120, it should be understood that a pull-to-open, push-to-close mechanism may alternatively be provided. For example, distal elements 120 may be coupled at their proximal ends to stud 131 rather than to coupling member 160, and legs 130 may be coupled at their proximal ends to coupling member 160 rather than to stud 131. In this example, when stud 131 is pushed distally relative to coupling member 160, distal elements 120 may close, while pulling on stud 131 proximally toward coupling member 160 may open distal elements 120. Regardless, the aforementioned lock examples may be configured to arrest stud to lock distal elements 120 in the desired position, as described.

[0184] It is to be understood that the fixation devices and components thereof described above are provided as examples are not to be considered as limiting to fixation devices suitable for use with other aspects of the disclosure.

[0185] The above-described examples of fixation device 112 may be utilized in a TEER procedure or any other tissue approximation procedures (e.g., procedures involving cardiac and non-cardiac tissues). A TEER procedure is a minimally invasive interventional procedure that aims to approximate cardiac valvular leaflets to reduce valvular regurgitation particularly in the mitral and triscupid valves. One of the challenges of this type of procedure is ensuring that the valve leaflets are adequately inserted into the fixation device, such as fixation device 112, for example, so that when the fixation device is deployed, it remains secured to the tissue and sufficiently reduces regurgitation. Current TEER techniques typically rely on echocardiography and fluoroscopy for visualization which typically capture fixed views of the target valve. Such visualization modalities, however, have inherent limitations that present challenges making leaflet capture and grasping one of, if not the most, challenging aspects of a TEER procedure. In particular, technique and technological limitations make it difficult to visually observe the leaflets within the fixation device during and after deployment so that the surgeon cannot directly observe how much leaflet is inserted into the fixation device or whetherAtty Docket No. ABTEVA-0063PCT a leaflet has been captured at all. Thus, surgeons typically assess leaflet capture through circumstantial observations that are heavily reliant on surgeon experience. For instance, a surgeon might detect changes in leaflet movement and reductions in backflow using color Doppler to assess whether a leaflet has been captured and evaluate the effectiveness of the capture.

[0186] Difficulties in visualizing leaflet capture can lead to poor leaflet securement and, ultimately, single leaflet device attachment (SLDA), where only one leaflet is captured by the fixation device, or complete detachment (implant embolization). For instance, if a leaflet is not inserted far enough between the proximal and distal elements (i.e., shallow leaflet insertion), the elements may lack the necessary force to properly grasp and retain the tissue, potentially causing leaflet slippage and leading to SLDA or implant embolization. Therefore, it is generally insufficient to merely capture valve tissue between the proximal and distal elements. Instead, the capture must be of sufficient quality to ensure the fixation device remains securely attached to the leaflet. The quality of tissue capture can be influenced by several factors, one of which is the magnitude of the pinch force applied to the tissue.

[0187] Finite element analysis has been performed to quantify the pinch force within corresponding proximal and distal elements to help determine how deep a leaflet may be inserted to achieve an adequality high probability that a leaflet will be permanently captured with limited or otherwise acceptable risk of SLDA or embolization. The force distribution resulting from this analysis for a first clamp 104 comprised of distal element 120 and proximal element 140 is shown in FIG. 20A and for a second, longer clamp 104’ comprised of distal element 120’ and proximal element 140’ is shown in FIG. 20B. As shown, the majority of the generated pinch force is applied to the tissue when approximately more than 50% of a maximum leaflet insertion depth is achieved. Thus, leaflet security is ensured, and leaflet capture is sufficient when a leaflet LF is inserted between proximal and distal elements to a depth of more than 50% of a maximum insertion depth. The maximum insertion depth Lgrip, as depicted in FIGS. 20A and 20B, is the maximum length along which a leaflet LF can be captured between the proximal and distal elements, such as proximal elements 120, 120’ and distal elements 140, 140’. The maximum insertion depth Lgrip may be measured between a crotch 105 (taking into account any fabric covering on the fixation device) formed between fixed ends 121a, 141a and free ends 121b, 141b of the respective distal elements 120, 120’ and proximal elements 140, 140’. Crotch 105 defines a closed end of clamps 104 and 104’. FreeAtty Docket No. ABTEVA-0063PCT ends 121b, 141b define an open end of clamps 104 and 104’. Although distal and proximal elements 120, 120’, 140, 140' typically capture tissue when each distal element 120, 120’ is at about 60 degrees relative to a longitudinal axis defined by shaft 111 (see FIG. 1 IB) (120 degrees relative each other) and are then moved to a final, closed position of 5 to 15 degrees (10 to 30 degrees relative each other), it should be noted that the pinch force generally does not change with the angle of the clamp 104, 104’ up to about the initial capture angle of 60 degrees. Thus, the pinch force will be approximately the same throughout the range of motion from initial capture to the final, closed position.

[0188] FIG. 21 illustrates a piezoelectric sensing system 700 according to an embodiment of the present disclosure. Sensing system 700 generally includes a signal processing unit 702, one or more piezoelectric sensors 720, and an interface 708 coupling sensors 720 to signal processing unit 700. As described further below, sensing system 700 can be integrated into a medical device or system and configured to detect and measure various conditions within a patient during a medical procedure.

[0189] Piezoelectric sensing system 700 may be configured in a pressure-sensing configuration in which at least one piezoelectric sensor is provided that includes a piezoelectric element made from one or more piezoelectric materials. In this configuration, mechanical forces applied to the piezoelectric element are converted into electrical signals. This conversion occurs as the applied pressure deforms the piezoelectric material, generating an electric charge proportional to the force. These electrical signals can then be processed to detect the application of pressure and analyze the magnitude of the applied forces.

[0190] Alternatively or additionally, piezoelectric sensing system 700 may be configured in an ultrasonic configuration. In this configuration, electrical current is applied to the piezoelectric element, causing it to vibrate and emit ultrasonic sound waves. The same piezoelectric element may also detect returning sound waves, converting them into corresponding electrical signals. This dual capability enables system 700 to function as both a transmitter and receiver (i.e., a transducer) of ultrasonic waves, allowing it to generate images and measure distances within a patient’s internal environment.

[0191] Signals generated by sensors 720 can be processed and converted into a readable output signal by signal processing unit 702, enabling a surgeon to assess conditions within the patient. As shown in FIG. 21, signal processing unit 702 generally includes a power source 704 and a signal processing module 706.Atty Docket No. ABTEVA-0063PCT

[0192] Power source 704 is configured to provide electrical energy to system 700, including any circuits that drive piezoelectric sensors 720 or process the generated signals. Power source 704 may be a DC power source, such as a battery or an external DC power adapter, for example. However, in some applications, an AC power source may be used, with AC to DC conversion implemented within system 700 for signal processing and sensor operation.

[0193] Signal processing module 706 is configured to receive and process signals generated by piezoelectric sensors 720. In this regard, signal processing module 706 handles one or more tasks, such as signal amplification, noise reduction, frequency filtering, and digital- to-analog conversion, for example. For instance, signal processing module 706 may include one or more amplifier circuits (e.g., operational amplifiers) to boost low-voltage signals to higher voltage levels, one or more filter circuits (e.g., low-pass and / or band-pass filters) to reduce or eliminate high-frequency noise that could interfere with signal interpretation, and / or an analog-to-digital converter (ADC) to transform analog signals into digital signals suitable for further processing by a processor or similar device. Additionally, in some configurations, signal processing module may incorporate a processor and memory to perform advanced signal processing tasks, such as Fourier Transform analysis and / or the application of machine learning algorithms for classifying patterns in the sensor output, for example.

[0194] As shown in FIG. 21, signal processing module 706 may communicate with an output device 710. This output device 710 may be a display (e.g., a monitor, touchscreen, projector, television, or other device capable of presenting information) or another visual indicator (e.g., LED array) that provides visual feedback to assist in a surgeon’s decisionmaking process. The results may be presented as raw data, such as pressure readings or signal magnitudes, or as processed interpretations of the signals generated by piezoelectric sensors 720, simplifying the decision-making process for the surgeon. Additionally, when multiple sensors 720 are utilized, signal processing module 706 can separate and analyze the signals from each sensor 720, outputting the results to output device 710. This enables the surgeon to identify which sensors 720 are activated and interpret the significance of the detected signals in real-time.

[0195] As shown in FIG. 21, sensor 720 represents one or more piezoelectric sensors, which may each be any one of various piezoelectric sensor types and / or configurations. For example, sensor 720 may be in the form of a standalone sensor (a single piezoelectric elementAtty Docket No. ABTEVA-0063PCT and corresponding electrical interface encased in an encapsulation) or arranged in a sensor array (a collection of multiple individual piezoelectric elements, each with a dedicated electrical interface, and collectively encased in a shared encapsulation). In this regard, the term “sensor” as used herein refers to a functional unit comprising a piezoelectric element (e.g., piezoelectric crystal or equivalent piezoelectric material) and an electrical interface (e.g., one or more electrodes) that together detect and transduce mechanical input (e.g., pressure, vibration, or force) into an electrical signal. This unit may operate independently (e.g., as a standalone sensor) or as part of an integrated array (e.g., a sensor array). Exemplary piezoelectric sensors that may be utilized in system 700 as standalone sensors or in a sensor array include, but are not limited to, Piezoelectric Micromachined Ultrasonic Transducers (“PMUTs”), which are a type of Micro-Electro-Mechanical Systems (“MEMS”).

[0196] Referring now in addition to FIGS. 22 A and 22B, which illustrate one example piezoelectric sensor 720’ that may be utilized in system 700. Sensor 720’ is a standalone sensor and generally includes a piezoelectric element 722, one or more electrodes 724, and an encapsulation 726. Piezoelectric element 722 forms the core of sensor 720’ and is configured to convert mechanical stress into an electrical signal. Piezoelectric element 720’ may be made from a piezoelectric ceramic such as quartz, lead zirconate titanate (PZT), or barium titanate, or alternatively, from a piezoelectric polymer, such as polyvinylidene fluoride (PVDF) or copolymers thereof.

[0197] Sensor 720’ may include one or more electrodes 724, but preferably at least two electrodes 724 positioned on opposite sides of piezoelectric element 722, as shown. These electrodes 724 enable the collection of electric charges generated by piezoelectric element 722 under mechanical stress. In some examples, electrodes 724 may be thin layers or films of conductive material, such as metals (e.g., gold, silver, platinum) or conductive polymers (e.g., polyaniline or poly(3,4-ethylenedioxythiophene), also referred to as PEDO T). Electrodes 724 ensure effective charge transfer while maintaining minimal interference with the deformation of the piezoelectric element 722. A lead 727 may be electrically coupled to each electrode 724 and extend therefrom to carry signals from electrodes 724 to signal processing unit 702.

[0198] Encapsulation 726 encases electrodes 724 and piezoelectric element 722, providing environmental protection and insulation. Additionally, encapsulation 726 forms a base layer 725a that connects to an underlying structure and a cover layer 726 that is exposed to the environment, where external forces may be applied to generate the intended deformationAtty Docket No. ABTEVA-0063PCT of piezoelectric element 722. Encapsulation 726 may be made from a flexible or rigid material, including biocompatible polymers (e.g., silicon, silicon nitride, silicon oxide, polyurethane, polyester, polypropylene, polyether block amide (“PEBAX”)), metals (e.g., titanium, stainless steel), or ceramics (e.g., alumina or zirconia).

[0199] Referring now in addition to FIGS. 23A and 23B, which depict a sensor array 730 comprising multiple piezoelectric sensors 720” which may be utilized in system 700. In the example shown, each sensor 720” includes a piezoelectric element 732 and a pair of electrodes 734a, 734b attached to opposite sides of piezoelectric element 732, as illustrated in FIG. 23B. Sensors 720” are arranged in a desired pattern, such as aligned rows and / or columns. In the depicted example, a plurality of sensors 720” are arranged in a single row and are collectively encased in an encapsulation 736. This row of sensors 720” may include two to four sensors 720”, for example. In other examples of sensor array 730, a second row of sensors 720” may be provided. Piezoelectric elements 732, electrodes 734a, 734b, and encapsulation 736 may be made from any of the materials described above in relation to sensor 720'.

[0200] As shown in FIG. 23 A, a set of leads 737a, 737b is electrically coupled to each sensor 720” to carry signals to signal processing unit 702. Each sensor 720” may have at least one dedicated lead, allowing the signals generated by each sensor 720” to be distinguished by signal processing unit 702. For example, first electrode 734a of each sensor 720” may be connected to a single lead 737a, while second electrode 734b of each sensor 720” may be connected to separate individual leads 737b, as shown in FIG. 23 A and FIG. 23B. This may allow signal processing unit 702 to distinguish signals generated by each sensor 720’ ’ . In other words, sensor array 730 allows sensors 720” to be spread out over an area in a consistent pattern which enables the detection of localized variations in conditions, such as pressure and / or force. By analyzing signals from individual sensors in the array 730, system 700 can create a spatial map of internal conditions, providing insights into how these variables are distributed across the monitored region.

[0201] Interface 708 between sensors 720 and signal processing unit 702 may be a hardwired interface or a wireless interface, for example. In a hardwired configuration, interface 708 may include one or more conductors, such as leads 727, 737a, 737b, which may carry electrical signals between sensors 720 and signal processing unit 702. Such configuration enables stable and reliable signal transmission with minimal noise interference. In a wireless configuration, interface 708 may additionally or alternatively include transmitters, receivers,Atty Docket No. ABTEVA-0063PCT and / or transceivers which may be enabled with any one of various wireless protocols (e.g., Bluetooth Low Energy (“BLE"), Near Field Communication (“NFC”), or Zigbee) to transmit signals from sensors 720 to signal processing unit 702.

[0202] Referring now in addition to FIG. 24, which illustrates an exemplary implementation of piezoelectric sensing system 700 in which one or more sensors 720 of sensing system 700 are coupled to one or more components of a fixation device 1012, which can be substituted for fixation device 1012 of FIG. 4, for example. Fixation device 1012 includes a first and second clamp 1004a, 1004b each comprised of a distal element 1020 and a proximal element 1040. Fixation device 1012 may also include a center portion 1060 disposed between each clamp 1004a, 1004b. When center portion 1060 is provided, first clamps 1004a extends outwardly relative to center portion 1060 for capturing a first tissue (e.g., a first valve leaflet), and second clamp 1004b extends outwardly relative to center portion 1060 for capturing a second tissue (e.g., a second valve leaflet).

[0203] The components of fixation device 1012 may be any of the components described above with respect to fixation device 112. In this regard, distal elements 1020 may be any of the aforementioned distal elements (e.g., distal elements 120) and may be operable via an actuator (e.g., actuator 113). Proximal elements 1040 may be any of the aforementioned proximal elements (e.g., proximal elements 140 or 240). Additionally, center portion 1060 may include a coupling member (e.g., coupling member 160 or 360) which is configured to releasably coupled to a catheter 1010. In another example, center portion 1060 may include a base (e.g., base 139) and / or a stud (e.g., 131) which may be coupled to fixation elements 1020 and may be configured to releasably coupled to an actuator rod (e.g., actuator rod 170) for actuation of distal elements 1020. In a further example, center portion 1060 may further include a lock (e.g., lock 116 or 515) configured to secure fixation elements 1020 in a selected position.

[0204] As illustrated in FIG. 24, one or more piezoelectric sensors 720a may be coupled to each distal element 1020, such as on an engagement surface (e.g., engagement surface 125) thereof. Thus, for example, when tissue is disposed within first clamp 1004a, and proximal element 1040 is moved into a lowered position to grasp tissue, the tissue is pressed into contact with distal element 1020 and sensor 720a. This pressure activates sensor 720a and generates a corresponding electrical signal which indicates that tissue is present within clamp and has been grasped. Additionally, the signal's characteristics can provide information about the magnitude of pressure, which may help the surgeon assess the quality of tissue interaction. Conversely, ifAtty Docket No. ABTEVA-0063PCT no signal is generated after proximal element 1040 is lowered (i.e., the orientation of FIG. 24), it indicates that tissue is either absent from first clamp 1004a or has not reached the location of sensor 720a. It should be noted that when proximal element 1040 is lowered toward a corresponding distal element 1020 to its greatest extent a gap may be formed between at least a portion of proximal element 1040 and distal element 1020 such that sensor 720a is not directly contacted by proximal element 1040 in the absence of tissue thus avoiding a potential false indication. However, in some examples, proximal element 1040 may directly contact sensor 720a in the absence of tissue. In such examples, the pressure applied by such direct contact may differ in magnitude than when tissue is present. Signal processing unit 702 may be configured to distinguish the differences in magnitude to provide the appropriate indication to the surgeon.

[0205] Additionally or alternatively, one or more sensors 720b, 720c may be coupled to each proximal element 1040. Each proximal element 1040 may have a plurality of frictional elements 1045, which may be like frictional elements 145 and 245, and an elongate body (e.g., arm 121 or 140). In one example, a sensor 720b may be coupled to one or more frictional elements 1045 of proximal element 1040. In another example, one or more sensors 720c may be coupled to an elongate body of proximal element 1040. In a further example, sensors 720b, 720c may be coupled to one or more frictional elements 1045 and the elongate body of proximal element 1040. Thus, when proximal element 1040 is lowered toward distal element 1020 to capture tissue, the one or more pressure sensors 720a, 720b are activated indicating the presence of tissue or are not activated indicating the absence of tissue within a respective clamp 1004a, 1004b.

[0206] Additionally or alternatively, one or more sensors 720d may be coupled to center portion 1060. As shown in FIG. 24, center portion 1060 is positioned between proximal elements 1040. When tissue is captured by clamps 1004a, 1004b, and clamps 1004a, 1004b are moved to a closed position adjacent to center portion 1060, tissue captured by clamps 1004a, 1004b may press against center portion 1060 and the one or more sensors 720d coupled thereto. If tissue is present within clamps 1004a, 1004b, sensors 720d coupled to center portion 1060 are activated to indicate the presence of the tissue. If tissue is not present within clamps 1004a, 1 04b, sensors 720d are not activated to indicate to the surgeon that regrasping may need to be performed.Atty Docket No. ABTEVA-0063PCT

[0207] FIG. 24 illustrates another exemplary implementation of piezoelectric sensing system 700 in which one or more sensors 720 of sensing system 700 are coupled to one or more components of an interventional system 1000 (or interventional tool as disclosed herein). Interventional system 1000 includes fixation device 1012 and a delivery catheter 1010. One or more sensors 720a-720d may be coupled to fixation device 1012 as described above. Additionally or alternatively, one or more sensors 720e may be coupled to a distal end of delivery catheter 1010. For example, the distal end of delivery catheter 1010 may include a shaft 1011 that is configured to releasably coupled to fixation device 1012, such as to center portion 1060. One or more sensors 720e may be coupled to shaft 1011 at respective locations between first and second clamps 1004a, 1004b. When tissue is captured or otherwise grasped by clamps 1004a, 1004b, and clamps 1004a, 1004b are moved to a closed position adjacent to shaft 1011, tissue captured by clamps 1004a, 1004b may press against shaft 1011 and sensors 720e coupled thereto. If tissue is present within clamps 1004a, 1004b (i.e., between distal and proximal elements 1020, 1040), sensors 720e are activated to indicate the presence of the tissue. If tissue is not present within clamps 1004a, 1004b or is not disposed to a desired depth between clamps 1004a, 1004b, sensors 720e will not be activated. The use of at least two sensors 720e disposed at opposite sides of shaft 101 1 provides a further indication to the surgeon whether tissue is present in both clamps 1004a, 1004b, in one clamp 1004a or 1004b, or in none of clamps 1004a, 1004b.

[0208] One or more sensors 720 may be located on any one of distal elements 1020, proximal elements 1040, center portion 1060, and catheter shaft 1011 and any combinations thereof. Providing sensors 720 on more than one component (e.g., on distal and proximal elements 1020, 1040), can provide redundancy and confidence that the signals being received are an accurate assessment of conditions within the patient.

[0209] Referring now in addition to FIGS. 25-39, which depict further exemplary sensor arrangements of interventional tool 1000 and fixation device 1012 thereof. In the following description of these sensor arrangement examples, reference to sensor 720 should be understood to include both standalone sensor 720’ or sensor 720” of sensor array 730 unless explicitly stated otherwise.

[0210] Referring now in particular to FIG. 25, which depicts a proximal element 1140 according to an example of fixation device 1012. Proximal element 1140 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned likeAtty Docket No. ABTEVA-0063PCT reference numerals but within a larger number series. Proximal element 1140 includes an elongate body 1141 and a plurality of frictional elements 1145. Elongate body 1141 defines a gripping length Lgrip extending from a first end 1141a (or fixed end) to a second end 1141b (or free end). In the example depicted, a sensor 720, which may be standalone sensor 720’, is positioned at a location between a midline ML of proximal element 1140 and fixed end 1141a of proximal element 1140. In other words, sensor 720 is positioned at a location beyond 50% of the grip length Lgrip of proximal element 1140 as measured from free end 1141b. Thus, when sensor 720 is activated by contact with tissue, such activation indicates that the tissue has been grasped and that the tissue extends at least to the location of sensor 720. Since sensor 720 is located at a location beyond 50% the grip length, the activation of sensor 720 may further indicate regrasping is not needed as the tissue may be considered sufficiently deep within clamp 1004a, 1004b to limit the risk of SLDA. The magnitude of the force measured by sensor 720 can further verify the quality of the grasp. For example, when a threshold force of 0.02 Ibf to 0.11 Ibf is measured, a sufficient grasp may be indicated, and a surgeon may then determine that a regrasping procedure is not needed. The threshold force may be tuned to account for the position of sensor 720 along proximal element 1140 such that the threshold force of a sensor 720 positioned closer to fixed end 1141 a may be higher than a threshold force of a sensor 720 positioned closer to free end. As such, a threshold force within a range of threshold forces (e.g., 0.02 Ibf to 0.11 Ibf) may be selected based on the position of sensor 720 on proximal element 1140, and the threshold force may differ for each position of sensor 720 along the grip length Lgrip.

[0211] Referring now in addition to FIG. 26, which depicts a proximal element 1240 according to another example of fixation device 1012. Proximal element 1240 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a sensor 720, which may be standalone sensor 720’, is positioned at the midline ML of proximal element. In other words, sensor 720 is positioned at 50% of the grip length Lgrip of proximal element 1240 as measured from free end 1241b. Thus, when sensor 720 is activated through contact with tissue, such activation indicates that tissue has been grasped and that the tissue extends to at least 50% of the total grip length Lgrip.

[0212] Referring now in addition to FIG. 27, which depicts a proximal element 1340 according to a further example of fixation device 1012. Proximal element 1340 is similar toAtty Docket No. ABTEVA-0063PCT proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 720a and a second sensor 720b are coupled to proximal element 1340. First and second sensors 720a, 720b may each be a standalone sensor, like sensor 720’, or may be part of a sensor array, like sensors 720’ ’ of sensor array 730. First and second sensors 720a, 720b in this example are coupled to elongate body 1341. First sensor 720a is positioned between a free end 1341b of proximal element 1340 and a midline ML of proximal element 1340. For example, first sensor 720a may be positioned between 0 and 25% of the grip length Lgrip as measured from free end 1341b. In another example, first sensor 720a may be positioned between 25% and 50% of the grip length Lgrip. Second sensor 720b is positioned between a fixed end 1341a of proximal element 1340 and the midline ML. For example, second sensor 720b may be positioned between 50% and 75% of the grip length Lgrip of proximal element 1340.

[0213] In operation, the activation of first sensor 720a but not second sensor 720b may indicate that tissue is present within a clamp 1004a, 1004b but has not reached a sufficient depth and that a regrasping procedure may be warranted. Similarly, regrasping may be indicated when proximal element 1340 is lowered in a grasping procedure and neither sensor 720a, 720b is activated. In contrast, the activation of both sensors 720a, 720b indicates that tissue is present within a corresponding clamp 1004a, 1004b and that the tissue has reached a sufficient depth such that clamp 1004a, 1004b may be moved to a closed position toward center portion 1060. Should second sensor 720b or first and second sensor 720a, 720b stop transmitting a signal while the clamp is closed, that may be an indication that the tissue has slipped and that the clamp 1004a, 1004b may need to be moved back to the open position and regrasping attempted.

[0214] Referring now in addition to FIG. 28, which depicts a proximal element 1440 according to another example of fixation device 1012. Proximal element 1440 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 820a and a second sensor 820b are coupled to proximal element 1440. First and second sensors 720a, 720b may each be a standalone sensor, like sensor 720’, or may be part of a sensor array, like sensors 720’ ’ of sensor array 730. First and second sensors 720a, 720b in this example are coupled to elongate body 1441. First sensor 720a is positionedAtty Docket No. ABTEVA-0063PCT between a free end 1441b of proximal element 1440 and a midline ML of proximal element 1440. For example, first sensor 720a may be positioned between 0 and 25% of the grip length Lgrip as measured from free end 1441b. In another example, first sensor 720a may be positioned between 25% and 50% of the grip length Lgrip. Second sensor 720b is positioned at the midline ML.

[0215] In operation, the activation of first sensor 720a but not second sensor 720b indicates that tissue is present between proximal element 1440 and a corresponding distal element (e.g., distal element 1020), but that the tissue may not be sufficiently deep thereby indicating that a regrasping operation may be warranted. Similarly, where neither sensor 720a, 720b is activated after lowering proximal element. However, the activation of both sensor indicates that tissue has reached at least 50% of the grip length Lgrip.

[0216] Referring now in addition to FIG. 29, which depicts a proximal element 1540 according to a further example of fixation device 1012. Proximal element 1540 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 720a is coupled to proximal element at the midline ML, and a second sensor 720b is coupled to proximal element 1540 at a location between the midline ML and a fixed end 1541a of proximal element 1540 (e.g., between midline ML and 75% of the grip length Lgrip).

[0217] In operation, the activation of first sensor 720a but not second sensor 720b indicates that tissue is present between proximal element 1540 and a corresponding distal element (e.g., distal element 1020), but has not reached second sensor 720b. In such circumstance, the surgeon may determine to perform a regrasping procedure. The magnitude of the force measured by sensor 720a can aid in this assessment. In contrast, the activation of both sensors 720a, 720b indicates that tissue has reached a sufficient depth to limit the risk of SLDA. The activation of both sensors 720a, 720b may provide additional confidence to the surgeon that tissue has been grasped up to the desired location.

[0218] Referring now in addition to FIG. 30, which depicts a proximal element 1640 according to an example of fixation device 1012. Proximal element 1640 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, first and second sensors 720a, 720b, which may each be standalone sensor 720’, are each coupled to aAtty Docket No. ABTEVA-0063PCT corresponding frictional element 1645a, 1645b of proximal element 1640. First sensor 720a and second sensor 720b may be positioned at any of the positions described above relative to midline ML but instead on a frictional element. Alternatively, as shown, first and second sensor 720a, 720b may be aligned in a direction transverse to a longitudinal axis of proximal element 1640 and coupled to frictional elements 1645a, 1645b at opposite sides of proximal element 1640. For example, first and second sensors 720a, 720b may be located at the midline or between the midline of proximal element 1640 and a fixed end thereof. Such positioning may provide redundancy. In this regard, the activation of both sensors 720a, 720b may provide additional confidence to the surgeon that tissue has been grasped up to the desired location. If only one of the sensors 720a, 720b is activated, it could be that one of the sensors 720a, 720b is not operable or that some other situation has occurred that may require troubleshooting. Magnitude measurements may further verify that tissue has nonetheless been appropriately grasped.

[0219] Referring now in addition to FIG. 31, which depicts a proximal element 1740 according to an example of fixation device 1012. Proximal element 1740 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. This example is similar to that of FIG. 30 with the exception that a first sensor 720a is coupled to the elongate body 1741 of proximal element 1740 and a second sensor 720b is coupled to a frictional element 1745 of proximal element 1440.

[0220] Referring now in addition to FIG. 32, which depicts a proximal element 1840 according to an example of fixation device 1012. Proximal element 1840 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 720a, a second sensor 720b, and a third sensor 720c are coupled to proximal element 1840, such as to the elongate body 1841 thereof. First sensor 720a is positioned between a free end 1841b (or second end) of proximal element 1840 and a midline ML of proximal element 1840 (e.g., between 0 and 25% or 25% and 50% of grip length Lgrip). Second sensor 720b is positioned at the midline ML. Third sensor 720c is positioned between the midline ML and a fixed end 1841a (or first end) of proximal element 1840 (e.g., between 50% and 75% of grip length Lgrip). This triple sensor configuration operates similar to the configurations of FIGS. 27-29 while providing enhanced resolution of the conditions at the target surgical site.Atty Docket No. ABTEVA-0063PCT

[0221] Referring now in addition to FIG. 33, which depicts a proximal element 1940 according to an example of fixation device 1012. Proximal element 1940 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 720a, a second sensor 720b, a third sensor 720c, and a fourth sensor 704d are coupled to a proximal element 1940, such as to the elongate body 1941 thereof. First and second electrodes 702a, 702b are positioned between a free end or second end 1941b of proximal element 1940 and a midline ML of proximal element 1940. For example, first sensor 720a may be positioned between 0 and 25% of the grip length Lgrip as measured from free end 1941b, and second sensor 720b may be positioned between 25% and 50% of the grip length Lgrip. Third sensor 720c is positioned at the midline ML. Fourth sensor 720d is positioned between the midline ML and a fixed end 1941b (or first end) of proximal element 1940 (e.g., between 50% and 75% of grip length Lgrip). This quadruple sensor configuration operates similar to the configurations of FIGS. 27-29 while providing enhanced resolution of the conditions at the target surgical site and added redundancy at each half of the grip length Lgrip.

[0222] Referring now in addition to FIG. 34, which depicts a proximal element 2040 according to an example of fixation device 1012. Proximal element 2040 is similar to proximal element 240 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this regard, proximal element 2040 is coupled to an arm bend feature 2060 which is coupled to a base 2050. Base 2050 may be coupled to a corresponding distal element (e.g., distal element 1020). Additionally, proximal element 2040 includes first and second side portions 2047 (or elongate members) which define a space 2048 (or window) therebetween. One or more sensors 720 may be coupled to base, and / or one or more sensors 720 may be coupled to proximal element 2040 at the depicted locations. For example, a sensor 720, such as sensor 720’, may be coupled to one or more frictional elements 2045.

[0223] Additionally or alternatively, one or more sensors 720 may be coupled to one or both side portions 2047. For example, one or both side portions 2047 may include a single sensor 720 at any location relative to midline ML as described with respect to FIGS. 25 and 26. In another example, one or both side portions 2047 may include a pair of sensors 720 at any location relative to midline ML as described with respect to FIGS. 27-29. In a furtherAtty Docket No. ABTEVA-0063PCT example, one or both side portions 2047 may include three sensors 720 at any location relative to midline ML as described with respect to FIG. 32.

[0224] Referring now in addition to FIG. 35, which depicts a distal element 2120 according to an example of fixation device 1012. Distal element 2120 is similar to distal element 120 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals. Additionally, unlike distal element 120, distal element 2120 may have wing portions 2123 extending laterally outwardly therefrom and extending along the grip length Lgrip between a first end 2121a (or fixed end) and a second end 2121b (or free end).

[0225] One or more sensors 720 may be coupled to distal element 2120 in addition to or as an alternative to any one of the aforementioned proximal element sensor configurations. For example, a single sensor 720 may be coupled to an engagement surface 2125 at any location relative to a midline ML of distal element 2120 as described with respect to FIGS. 25 and 26. In another example, a pair of sensors 720 may be coupled to engagement surface 2125 at any location relative to midline ML as described with respect to FIGS. 27-29. In a further example, three sensors 720 may be coupled to engagement surface 2125 at any location relative to midline ML as described with respect to FIG. 32. In another example, four sensors 720 may be coupled to engagement surface 2125 at any location relative to midline ML as described with respect to FIG. 33.

[0226] Additionally or alternatively, one or more sensors 720 may be coupled to one or both wing extensions 2123, such as at the midline ML, between free end 2121b and the midline ML, and / or between the midline ML and fixed end 2121a.

[0227] Although each of the foregoing example sensor configurations on proximal and distal elements are shown and described as being on a single proximal element or a single distal element, it should be understood that in a fixation device, such as fixation device 1012, the same electrode configurations may be implemented on the other proximal and distal element in the fixation device.

[0228] Referring now in addition to FIG. 36, which depicts a distal end of an interventional tool 2200 which includes a catheter shaft 2211 and a fixation device 2212. Fixation device 2212 and catheter shaft 2211 can be similar to that of interventional tool 1000 except as explicitly stated. In this regard, fixation device 2212 includes a central portion 2260 which, in this example, is coupling member for coupling fixation device 2212 to catheter shaft 2211. One or more sensors 720, such as standalone sensor 720’, may be coupled to couplingAtty Docket No. ABTEVA-0063PCT member 2260. For example, a first sensor 720a may be positioned at one side of coupling member 2260, and a second sensor 720b may be positioned an opposite side of coupling member 2260. In operation, when it is suspected that tissue has been captured by fixation device 2212 (e.g., by visualizing leaflet behavior in fluoroscopic and / or echocardiographic images), first and second distal elements 2220a, 2220b may be closed into a position adjacent to coupling member 2260. If tissue is captured by fixation device 2212, the tissue will contact sensors 720a, 720b which activates sensors 720a, 720b and indicates or otherwise confirms tissue capture. Sensors 720a, 720b may be positioned along a length of coupling member 2260 such that when distal elements 2220a, 2220b are closed, such as to an angle of 10 to 30 degrees between them, sensors 720a, 720b may be located at a position that is at 50% (+ / - 5%) or greater than 50% the length of the corresponding distal elements 2220a, 2220b.

[0229] Referring now in addition to FIG. 37, which depicts an interventional tool 2300 which includes a catheter shaft 2311 and a fixation device 2312. Fixation device 2312 and catheter shaft 2311 are similar to that of interventional tool 1000 except as explicitly stated. In this regard, fixation device 2312 includes a central portion 2360 which is coupling member for coupling fixation device 2312 to catheter shaft 2311. One or more sensors 720, such as standalone sensor 720’, may be coupled to catheter shaft 231 1. For example, a first sensor 720a may be positioned at one side of catheter shaft 2311, and a second sensor 720b may be positioned an opposite side of catheter shaft 2311. In operation, when it is suspected that tissue has been captured by fixation device 2312 (e.g., by visualizing leaflet behavior in fluoroscopic and / or echocardiographic images), first and second distal elements 2320a, 2320b may be closed into a position adjacent to catheter shaft 2311. If tissue is captured by fixation device 2312, the tissue will contact sensors 720a, 720b which activates sensors 720a, 720b and indicates or otherwise confirms tissue capture.

[0230] Additionally, in some examples, the fixation device 2212 of FIG. 36 may be combined with the catheter 2311 of FIG. 37 such that sensors 720 are positioned on both a catheter shaft and a fixation device coupling member.

[0231] Referring now in addition to FIG. 38, which depicts a fixation device 2412. Fixation device 2412 is similar to fixation device 1012 except as explicitly stated. In this regard, fixation device 2412 includes a central portion 2260 which, in this example, is a compressible coaptation body. Coaptation body 2460 extends outwardly relative to a central axis of fixation device 2412 and may taper inwardly in a proximal to distal direction. Coaptation body 2412 isAtty Docket No. ABTEVA-0063PCT positioned between distal elements 2420a, 2420b when distal elements 2420a, 2420b are in a closed position. When tissue is captured by distal elements 2420a, 2420b and associated proximal elements (e.g., proximal elements 1040) and distal elements 2420a, 2420b are closed adjacent to coaptation body 2460, coaptation body 2460 compresses inwardly and provides an additional seal between opposing tissues (e.g., valve leaflets).

[0232] One or more sensors 720, such as standalone sensor 720’, may be coupled to coaptation body 2460. For example, a first sensor 720a may be positioned at one side of coaptation body 2460, and a second sensor 720b may be positioned an opposite side of coaptation body 2460. Such sensors 720a, 720b may be activated by the compression of coaptation body 2460 or by direct pressure by tissue captured by distal elements 2420a, 2420b to indicate tissue has indeed been captured. Sensors 720a, 720b may be positioned along a length of coaptation body 2460 such that when distal elements 2420a, 2420b are closed, such as to an angle of 10 to 30 degrees between them, sensors 720a, 720b may be located at a position that is at 50% (+ / - 5%) or greater than 50% the length of the corresponding distal elements 2420a, 2420b.

[0233] Referring now in addition to FIG. 39, which is a schematic cross-section representative of the examples of FIGS. 36-38. Tn this regard, a center portion 2560 is representative of coupling member 2260 of FIG. 36, catheter shaft 2311 of FIG. 37, and coaptation body 2460 of FIG. 38. As shown, center portion 2560 is positioned between opposing clamps 2504a, 2504b each comprised of a distal element 2520 and a proximal element 2540. A first plane Pl bisecting center portion 2560 is positioned approximately equidistant between first and second clamps 2504a, 2504b. As second plane P2 is oriented perpendicular the first plane Pl and intersects first and second clamps 2504a, 2504b.

[0234] In the example depicted, first and second sensors 720a, 720b, such as sensor 720’, may be positioned at opposite sides of center portion 2560 and between first and second planes Pl, P2, such as 45 degrees offset therefrom, for example. Such orientation of sensors 720a, 720b prevents sensors 720a, 720b from being contacted by proximal elements 2540 when clamps 2504a, 2504b are moved to a closed position. However, tissue extending from each clamp 2504a, 2504b is allowed to contact sensors 720a, 720b thereby activating sensors 720a, 720b and indicating that tissue capture has occurred. Additionally, by positioning sensors 720a, 720b at these locations, first sensor 720a is configured to detect tissue within first clamp 2504a, and second sensor 720b is configured to detect tissue within second clamp 2504b.Atty Docket No. ABTEVA-0063PCT

[0235] Referring now in addition to FIGS. 40 A and 40B, which depict another exemplary piezoelectric sensor 820 that may be utilized in system 700. Sensor 820 is a strip sensor characterized by a flexible and elongate structure with a thinner profile compared to sensors 720’ and 720”. For example, sensor 820 may have a length-to- width ratio of at least 2:1, where the length L is depicted in FIG. 40A, and the width is measured transverse to the length L. Sensor 820 generally includes a piezoelectric element 822, a pair of electrodes 824, and an encapsulation 826. Piezoelectric element 822 is configured to convert mechanical stress into an electrical signal and is made from a flexible piezoelectric material, such as PVDF or copolymers thereof, for example.

[0236] Electrodes 824 are positioned along opposite sides of piezoelectric element 822, as shown in FIG. 40B. These electrodes 824 enable the collection of electric charges generated by piezoelectric element 822. To maintain the elongate and flexible structure of sensor 820, electrodes 824 may be made from thin and flexible conductive materials, such as metallic inks (e.g., silver or gold ink) or conductive polymers (e.g., PEDOT), for example. A lead 827 may be electrically coupled to each electrode 824 and extend from sensor 820 to transmit the generated signals to signal processing unit 702.

[0237] Encapsulation 826 encases piezoelectric element 822 and electrodes 824, providing environmental protection and electrical insulation. Encapsulation 826 may be in the form of a thin, flexible coating and can be made from biocompatible materials such as silicone, polyurethane, or parylene, for example. Additionally, encapsulation 826 may help maintain the structural integrity of sensor 820 while allowing it to flex and conform to non-planar surfaces.

[0238] The elongate shape and flexible characteristic of sensor 820 enables it to be used on curved or irregular surfaces. Additionally, its low-profile nature minimizes interference with the functionality of the structure to which it is attached. Furthermore, the strip configuration allows sensor 820 to monitor pressure, strain, or other mechanical forces over a larger surface area compared to standalone or array-based sensors like sensors 720’ and 720” . This capability makes strip sensor 820 particularly beneficial for applications involving distributed sensing across elongated or flexible regions.

[0239] Referring now in addition to FIG. 41, which illustrates an exemplary implementation of sensors 820 in a fixation device 2612. Sensors 820 may be utilized within sensing system 700 and may be coupled to one or more components of a fixation device 2612. Fixation device 2612 is like fixation device 1012 in that it includes a first and second clampAtty Docket No. ABTEVA-0063PCT2604a, 2604b each comprised of a distal element 2620 and a proximal element 2640. Additionally, fixation device 2612 may also include a center portion 2660 disposed between each clamp 2604a, 2604b. Also, like fixation device 1012, each of the components of fixation device 2612 (e.g., distal elements 2620, proximal elements 2640, and center portion 2660) may be any of the components described above with respect to fixation device 112.

[0240] As illustrated in FIG. 41 , one or more piezoelectric sensors 820a may be coupled to each distal element 2620, such as on an engagement surface (e.g., engagement surface 125) thereof. In this regard, strip sensor 820 may extend along a portion of a length of each distal element 2620 or an entire length of each distal element 2620. This allows sensor 820a to detect tissue engagement with any part of the length occupied by strip sensor 820a. Thus, for example, when tissue is disposed within first clamp 2604a, and proximal element 2640 is moved into a lowered position for grasping, the tissue is pressed into contact with distal element 2620. If the tissue is located along any portion of strip sensor 820a, the pressure from the grasping of the tissue activates sensor 820a and generates a corresponding electrical signal which indicates that tissue is present within clamp 2604a and within the region of sensor 820a. Additionally, the signal's characteristics can provide information about the magnitude of pressure, which may help the surgeon assess the quality of tissue interaction.

[0241] Additionally or alternatively, one or more sensors 820b may be coupled to each proximal element 2640. Each proximal element 2640 may have a plurality of frictional elements 2645, which may be like frictional elements 145 and 245, and an elongate body (e.g., arm 121 or 140). In one example, one or more sensors 820b may be coupled to the elongate body of each proximal element 2040 such that sensor 820b extends along a portion of a length of each corresponding proximal element 2040 or along an entire length of thereof. Due to the elongate structure of strip sensor 820b, sensor 820b may not be suitable to be coupled to frictional elements 2645. However, it is contemplated that sensor 820b may be modified such as by shaping portions of strip sensor 820b (e.g., providing ribbons extending from a main body of sensor 820b) to extend from the elongate body of proximal portion 2614 onto some or all frictional elements 2645. Thus, when proximal element 2640 is lowered toward distal element 2620 to capture tissue, sensor 820b is activated when the tissue comes into contact with a region occupied by sensor 820b indicating the presence of tissue in that region. Conversely, when sensor 820b is not activated, that is an indication that tissue has not been grasped or reached that region of proximal element 2640.Atty Docket No. ABTEVA-0063PCT

[0242] Additionally or alternatively, one or more sensors 820c may be coupled to center portion 2660. As shown in FIG. 41, center portion 2660 is positioned between proximal elements 2640. For example, one or more strip sensors 820c may be positioned on center portion 2660 such that each sensor 820c extends about a portion or an entirety of a perimeter of center portion 2660. When tissue is captured by clamps 2604a, 2604b, and clamps 2604a, 2604b are moved to a closed position adjacent to center portion 2660, tissue captured by clamps 2604a, 2604b may press against center portion 2660 and the one or more sensors 820c coupled thereto. If tissue is present within clamps 2604a, 2604b, sensors 820c are activated to indicate the presence of the tissue. If tissue is not present within clamps 2604a, 2604b, sensors 820c are not activated to indicate to the surgeon that regrasping may need to be performed.

[0243] FIG. 41 further illustrates another exemplary implementation in which one or more sensors 820a-820c are coupled to one or more components of an interventional system 2600 (or interventional tool). Interventional system 2600 includes fixation device 2612 and a delivery catheter 2610. One or more sensors 820a-820c may be coupled to fixation device 2612 as described above. Additionally or alternatively, one or more sensors 820d may be coupled to a distal end of delivery catheter 2610. For example, distal end of delivery catheter 2610 may include a shaft 261 1 that is configured to releasably couple to fixation device 2612, such as to center portion 2660. One or more sensors 820d may be coupled to shaft 2611. For example, one or more sensors 820d may extend about a portion or an entirety of a perimeter of shaft 2611, as illustrated in FIG. 41. When tissue is captured by clamps 2604a, 2604b, and clamps 2604a, 2604b are moved to a closed position adjacent to shaft 2611, tissue captured by clamps 2604a, 2604b may press against shaft 2611 and sensors 820d coupled thereto. If tissue is present within clamps 2604a, 2604b, sensors 820d are activated to indicate the presence of the tissue. If tissue is not present within clamps 2604a, 2604b or is not disposed to a desired depth between clamps 2604a, 2604b, sensors 820d will not be activated.

[0244] It is noted that utilizing such strip sensors 820 in the manner described above within a cardiovascular system to detect tissue engagement, signals generated by each sensor 820 may indicate an oscillating force due to the cardiac cycle of systole and diastole. Such force reading may not reflect tissue contact with sensor 820. As such, corrections can be made such as by waiting for time varying pressure signals to dissipate after contact with the tissue, or signal processing unit 702 may be configured to subtract the cardiac pressure effect by other patient monitoring occurring concomitantly (e.g., dynamic pigtail pressure reading in theAtty Docket No. ABTEVA-0063PCT cardiac chambers or other systemic blood pressure measurements based on arterial compliance).

[0245] One or more sensors 820 may be located on any one of distal elements 2620, proximal elements 2640, center portion 2660, and catheter shaft 261 1 and any combinations thereof. Providing sensors 820 on more than one component (e.g., on distal and proximal elements 2620, 2640), can provide redundancy and confidence that the signals being received provide an accurate assessment of conditions within the patient.

[0246] Referring now in addition to FIGS. 42-50, which depict further exemplary sensor arrangements of interventional tool 2600 and fixation device 2612 thereof.

[0247] Referring now in addition to FIG. 42, which depicts a proximal element 2740 according to an example of fixation device 2612. Proximal element 2740 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. Proximal element 2740 includes an elongate body 2741 and a plurality of frictional elements 2745. Elongate body 2741 defines a gripping length Lgrip extending from a first end 2741a (or fixed end) to a second end 2741b (or free end). In the example depicted, a sensor 820 is positioned at a location between a midline ME of proximal element 2740 and fixed end 2741 a of proximal element 2740. Since sensor 820 is a strip sensor, it may extend along a designated length within this region (i.e., between the midline ML and fixed end 2741a). Thus, in one example configuration, sensor 820 may extend along the length extending from midline ML to 75% of the grip length Lgrip as measured from free end 2741b. In another example configuration, sensor 820 may extend along the length extending from 75% of the grip length Lgrip as measured from free end 2741b to fixed end 2741a. In a further example configuration, sensor 820 may extend along the length extending from the midline ML to fixed end 2741a. Thus, if tissue enters into a clamp 2640a, 2640b in a direction from free end 2741b towards fixed end 2741a, sensor 820 will be activated when the tissue is located within any of these regions thereby indicating that the tissue has been grasped and that the tissue is located in the region of sensor 820. Since the region occupied by sensor 820 in each of these example configurations is located beyond 50% the grip length Lgrip, the activation of sensor 820 may further indicate regrasping is not needed as the tissue may be considered sufficiently deep within clamp 2640a, 2640b to limit the risk of SLDA. The magnitude of the force measured by sensor 720 can further verify the quality of the grasp.Atty Docket No. ABTEVA-0063PCT

[0248] Referring now in addition to FIG. 43, which depicts a proximal element 2840 according to an example of fixation device 2612. Proximal element 2840 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 820a and a second sensor 820b are coupled to proximal element 2840. First sensor 820a is positioned at a location between a free end 2841b of proximal element 28040 and a midline ML of proximal element 2840. Since first sensor 820a is a strip sensor, it may extend along a designated length within this region (i.e., between free end 2841b and midline ML). Thus, in one example configuration, first sensor 820a may extend along a length extending from free end 2841b to 25% of the grip length Lgrip as measured from free end 1341b. In another example configuration, first sensor 820a may be extend along a length extending from 25% to 50% of the grip length Lgrip. In a further example configuration, first sensor 820a may extend along a length extending from free end 2841b to midline ML.

[0249] Additionally, second sensor 820b is positioned at a location between midline ML of proximal element 2840 and fixed end 2841a of proximal element 2840. Since second sensor 820b is a strip sensor, it may extend along a designated length within this region (i.e., between the midline ML and fixed end 2841a). Thus, in one example configuration, second sensor 820b may extend along the length extending from midline ML to 75% of the grip length Lgrip as measured from free end 2841b. In another example configuration, sensor 820b may extend along the length extending from 75% of the grip length Lgrip as measured from free end 2841b to fixed end 2841a. In a further example configuration, second sensor 820b may extend along the length extending from the midline ML to fixed end 2841a. Thus, in some examples, first and second sensors 820a, 820b may be positioned back-to-back along a longitudinal axis LA of proximal element 2840.

[0250] In operation, the activation of first sensor 820a but not second sensor 820b may indicate that tissue is present within a clamp 2604a, 2604b at the first region of first sensor 820a but has not reached a sufficient depth to reach the region of second sensor 820b. In such circumstance, a regrasping procedure may be warranted. Similarly, regrasping may be indicated when proximal element 2840 is lowered in a grasping procedure and neither sensor 820a, 820b is activated. In contrast, the activation of both sensors 820a, 820b indicates that tissue is present within a corresponding clamp 2604a, 2604b and that the tissue has reached a sufficient depth such that clamp 2604a, 2604b may be moved to a closed position toward centerAtty Docket No. ABTEVA-0063PCT portion 2660. Should second sensor 820b or first and second sensor 820a, 820b stop transmitting a signal while the clamp 2604a, 2604b is closed, that may be an indication that the tissue has slipped out of at least one of these regions and that the clamp 2604a, 2604b may need to be moved back to the open position and regrasping attempted.

[0251] Referring now in addition to FIG. 44, which depicts a proximal element 2940 according to an example of fixation device 2612. Proximal element 2940 is similar to proximal element 140 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals but within a larger number series. In this example configuration, a first sensor 820a, a second sensor 820b, a third sensor 820c, and a fourth sensor 820d are coupled to a proximal element 2940, such as to the elongate body 2941 thereof. Since sensors 820a- 820d are each strip sensors, they each extend along a designated length of proximal element 2940. Thus, in the example depicted, first sensor 820a extends along a length extending from free end 2941b to 25% of the grip length Lgrip as measured from free end 2941b. Second sensor 820b extends along a length extending from 25% to 50% of the grip length Lgrip. Third sensor 820c extends along a length extending from 50% to 75% of the grip length Lgrip. Fourth sensor 820d extends along a length extending from 75% of the grip length Lgrip to fixed end 2941 a. This configuration enables the surgeon to gain insight into the conditions within each quadrant of proximal element 2940 during a grasping procedure.

[0252] Referring now in addition to FIG. 45, which depicts a proximal element 3040 according to an example of fixation device 2612, which can be substituted for fixation device 112, for example. In this regard, proximal element 3040 is coupled to an arm bend feature 3060 which is coupled to a base 3050. Base 3050 may be coupled to a corresponding distal element (e.g., distal element 3050). Additionally, proximal element 3040 includes first and second side portions 3047 (or elongate members) which define a space 3048 (or window) therebetween. One or more sensors 820 may be coupled to base 3050, and / or one or more sensors 820 may be coupled to one or more side portions 3047 proximal element 3040 at the depicted locations. For example, one or both side portions 3047 may include a first sensor 820 at any location relative to midline ML as described with respect to FIG. 42. In another example, one or both side portions 3047 may include a pair of sensors 820a, 820b at any location relative to midline ML as described with respect to FIGS. 43.

[0253] Referring now in addition to FIG. 46, which depicts a proximal element 3120 according to an example of fixation device 2612, which can be substituted for fixation deviceAtty Docket No. ABTEVA-0063PCT112, for example. Referring now in addition to FIG. 46, which depicts a distal element 3120 according to an example of fixation device 2612. Distal element 3120 is similar to distal element 120 and can be used interchangeably, and accordingly, like elements are assigned like reference numerals. Additionally, unlike distal element 120, distal element 3120 may have wing portions 3123 extending laterally outwardly therefrom and extending along the grip length Lgrip between a first end 3121a (or fixed end) and a second end 3121b (or free end).

[0254] One or more sensors 820 may be coupled to distal element 3120 in addition to or as an alternative to any one of the aforementioned proximal element sensor configurations. For example, a single sensor 820 may be coupled to an engagement surface 3125 at any location relative to a midline ML of distal element 3120 as described with respect to FIGS. 42. In another example, a pair of sensors 820 may be coupled to engagement surface 325 at any location relative to midline ML as described with respect to FIGS. 43. In a further example, four sensors 820 may be coupled to engagement surface 3125 at any location relative to midline ML as described with respect to FIG. 44.

[0255] Additionally or alternatively, one or more sensors 820 may be coupled to one or both wing extensions 3123, such as between free end 3121b and the midline ML, and / or between the midline ML and fixed end 3121 a.

[0256] Although each of the foregoing example sensor configurations on proximal and distal elements are shown and described as being on a single proximal element or a single distal element, it should be understood that in a fixation device, such as fixation device 2612, the same electrode configurations may be implemented on the other proximal and distal element in the fixation device.

[0257] Referring now in addition to FIG. 47, which depicts an interventional tool 3200 which includes a catheter shaft 3211 and a fixation device 3212. Fixation device 3212 and catheter shaft 3211 are similar to that of interventional tool 2600 and can be similarly configured and operate in a similar manner. In this regard, fixation device 3212 includes a central portion 3260 which, in this example, is coupling member for coupling fixation device 3212 to catheter shaft 3211. A sensor 820 is coupled to coupling member 3260. Since sensor 820 is a strip sensor with an elongate structure, sensor may be wrapped about at least a portion of a perimeter coupling member 3260, as illustrated. However, in other examples, sensor 820 may extend along the length of coupling member 3260. In further examples, more than one strip sensor 820 may be provided and may either be stacked adjacent to one another or in anAtty Docket No. ABTEVA-0063PCT offset relationship relative to one another. In operation, when it is suspected that tissue has been captured (e.g., by visualizing leaflet behavior in fluoroscopic and / or echocardiographic images) by fixation device 3212, first and second distal elements 3220a, 3220b may be closed into a position adjacent to coupling member 3260. If tissue is captured by fixation device 3212, the tissue will contact sensor 820 which activates sensor 820 and indicates or otherwise confirms tissue capture. Sensor 820 may be positioned at a location along the length of coupling member 3260 such that when distal elements 3220a, 3220b are closed, such as to an angle of 10 to 30 degrees between them, sensor 820 may be located at a position that is at 50% (+ / - 5%) or greater than 50% the length of the corresponding distal elements 3220a, 3220b.

[0258] Referring now in addition to FIG. 48, which depicts an interventional tool 3300 which includes a catheter shaft 3311 and a fixation device 3312. Fixation device 3312 and catheter shaft 3311 are similar to that of interventional tool 2600 and can otherwise be similarly configured and operate in a similar manner. In this regard, fixation device 3312 includes a central portion 3360 which is coupling member for coupling fixation device 3312 to catheter shaft 3311. A sensor 820 is coupled to catheter shaft 3311. Since sensor 820 is a strip sensor with an elongate structure, sensor may be wrapped about at least a portion of a perimeter catheter shaft 3260, as illustrated. However, in other examples, sensor 820 may extend along the length of catheter shaft 3211. In further examples, more than one strip sensor 820 may be provided and may either be stacked adjacent to one another or in an offset relationship relative to one another. In operation, when it is suspected that tissue has been captured by fixation device 3212 (e.g., by visualizing leaflet behavior in fluoroscopic and / or echocardiographic images), first and second distal elements 3220a, 3220b may be closed into a position adjacent to catheter shaft 3211. If tissue is captured by fixation device 3212, the tissue will contact sensor 820 which activates sensors 820 and indicates or otherwise confirms tissue capture.

[0259] Additionally, in some examples, the fixation device 3212 of FIG. 46 may be combined with the catheter 3311 of FIG. 47 such that sensors 820 are positioned on both a catheter shaft and a fixation device coupling member.

[0260] Referring now in addition to FIG. 49, which depicts a fixation device 3412. Fixation device 3412 is similar to fixation device 2612 and can otherwise be similarly configured and operate in a similar manner. In this regard, fixation device 3412 includes a central portion 3460 which, in this example, is a compressible coaptation body. Coaptation body 3460 extends outwardly relative to a central axis of fixation device 3412 and may taperAtty Docket No. ABTEVA-0063PCT inwardly in a proximal to distal direction. Coaptation body 3460 is positioned between distal elements 3420a, 3420b when distal elements 3420a, 3420b are in a closed position. When tissue is captured by distal elements 3420a, 3420b and associated proximal elements (e.g., proximal elements 1040) and distal elements 3420a, 3420b are closed adjacent to coaptation body 3460, coaptation body 3460 compresses inwardly and provides an additional seal between opposing tissues (e.g., valve leaflets).

[0261] A sensor 820 is coupled to coupling member 3460. Since sensor 820 is a strip sensor with an elongate structure, sensor may be wrapped about at least a portion of a perimeter coaptation body 3460, as illustrated. However, in other examples, sensor 820 may extend along the length of coaptation body 3460. In further examples, more than one strip sensor 820 may be provided and may either be stacked adjacent to one another or in an offset relationship relative to one another. In operation, when it is suspected that tissue has been captured by fixation device 3412 (e.g., by visualizing leaflet behavior in fluoroscopic and / or echocardiographic images), first and second distal elements 3420a, 3420b may be closed into a position adjacent to coaptation body 3460. If tissue is captured by fixation device 3412, the tissue will contact sensor 820 which activates sensor 820 and indicates or otherwise confirms tissue capture. Sensor 820 may be positioned at a location along the length of coaptation body 3460 such that when distal elements 3420a, 3420b are closed, such as to an angle of 10 to 30 degrees between them, sensor 820 may be located at a position that is at 50% (+ / - 5%) or greater than 50% the length of the corresponding distal elements 3420a, 3420b.

[0262] Referring now in addition to FIG. 50, which is a schematic cross-section representative of the examples of FIGS. 47-49. In this regard, a center portion 3560 is representative of coupling member 3260 of FIG. 47, catheter shaft 3311 of FIG. 48, and coaptation body 3460 of FIG. 49. As shown, center portion 3560 is positioned between opposing clamps 3504a, 3504b each comprised of a distal element 3520 and a proximal element 3540. A first plane Pl bisecting center portion 3560 is positioned approximately equidistant between first and second clamps 3504a, 3504b. As second plane P2 is oriented perpendicular the first plane Pl and intersects first and second clamps 3504a, 3504b.

[0263] In the example depicted, sensor 820 may extend about a portion of center portion 3560 and may intersect first plane Pl, but not second plane P2. For example, sensor may extend along an arc length of about 90 degrees from a first side of first plane Pl to a second side of plane Pl. Such arrangement of sensor 820 prevents 820 from being contacted byAtty Docket No. ABTEVA-0063PCT proximal elements 3540 when clamps 3504a, 3504b are moved to a closed position while allowing tissues extending from clamps 3504a, 3504b to contact sensor. The magnitude of the force registered by sensor 820 may be used by sensing system 700 to determine if tissue is captured by both clamps 3504a, 3504b, or only one of clamps 3504a, 3504b.

[0264] Referring now in addition to FIG. 51, which depicts another exemplary piezoelectric sensor 920 that may be utilized in system 700. Sensor 920 is in the form of a piezoelectric ultrasound transducer. In this regard, sensor 920 is configured to operate as both a transmitter and receiver of ultrasonic sound waves. Sensor 920 generally includes a housing 926, a backing layer 921, a piezoelectric element 922, a matching layer 923, and an acoustic lens 925.

[0265] Piezoelectric element 922 is configured to convert electrical signals into mechanical vibrations, thereby generating ultrasonic sound waves, and conversely, to detect returning sound waves and convert them into corresponding electrical signals. This dual functionality allows sensor 920, in conjunction with signal processing unit 702, to generate images and / or measure distances within a patient' s internal environment. Piezoelectric element 922 forms the core of sensor 920 and may be made from a piezoelectric ceramic material, such as lead zirconate titanate (PZT) or barium titanate, for example. In some configurations, piezoelectric element 922 may be made from a piezoelectric polymer, such as PVDF. Piezoelectric element 922 is positioned within housing 926, which provides mechanical support and protection for the internal components of sensor 920.

[0266] Backing layer 921 is disposed at a first side (or rear side) of piezoelectric element 922 and is configured to absorb and dissipate extraneous acoustic energy, thereby preventing echoes and enhancing the resolution of sensor 920. Backing layer 921 may be made from a material with high acoustic impedance, such as an epoxy resin embedded with metal powders, which effectively dampens vibrations and improves the sensitivity of sensor 920.

[0267] Matching layer 923 is disposed at a second side (or front side) of piezoelectric element 922 and is configured to match the acoustic impedance between piezoelectric element 922 and the surrounding medium (e.g., tissue or blood). This impedance matching enhances the efficiency of sound wave transmission and reception. Matching layer 923 may be made from a biocompatible material with an acoustic impedance similar to that of tissue or fluid (e.g., blood), such as polyurethane or a silicone -based material.Atty Docket No. ABTEVA-0063PCT

[0268] Acoustic lens 925 is positioned at the front of sensor 920 and is configured to direct ultrasonic waves generated by piezoelectric element 922 into the surrounding tissue or fluid (e.g., blood) and to gather returning signals for redirection back to the piezoelectric element 922. Lens 925 controls the width and shape of the ultrasonic waves as they exit sensor 920 and re-enter sensor 920 from the surrounding environment. Acoustic lens 925 may be made from a biocompatible material such as polycarbonate or optical-grade silicone for durability and acoustic transparency.

[0269] Referring now in addition to FIG. 52, which depicts an exemplary implementation of sensors 920. In this example, an interventional system 3600 (or interventional tool) includes a fixation device 3612 and a delivery catheter 3610. Delivery catheter 3610 may have a main body 3612 with a plurality of lumens extending therethrough and a shaft 3611 extending distally from main body 3612. Fixation device 3612 may include any other aspects of and may operate similar to any of the aforementioned fixation devices (e.g., fixation device 112, 1012, or 2612). Thus, in some examples, fixation device 3612 may have one or more sensors (e.g., sensor 720 or 820) coupled thereto as described with respect to fixation devices 1012 and 2612.

[0270] As illustrated, a first sensor 920a and a second sensor 920b are coupled to the distal end of the main body 3612 of the delivery catheter 3610. Each sensor 920a, 920b is arranged to emit ultrasonic waves directed toward a corresponding clamp 3604a, 3604b when the clamps 3604a, 3604b are in an open position. For instance, a first piezoelectric ultrasonic sensor 920a is oriented toward a first clamp 3604a, while a second piezoelectric ultrasonic sensor 920b is directed toward a second clamp 3604b. These ultrasonic waves are emitted at an acute angle relative to a longitudinal axis of catheter shaft 3611, as shown in FIG. 52. For example, distal elements 3620 may be oriented 60 degrees (+ / - 5 degrees) relative to shaft 3611 when in an open position. Sensors 920a, 920b may be arranged such that waves emanating therefrom are directed perpendicular (+ / - 5 degrees) to their respective distal elements 3620 in the open position. As such, in this example, the acute angle may be 30 degrees (+ / - 5 degrees). Leads 927 may extend from each sensor 920a, 920b and extend through catheter 3610, such as one or more of the lumens thereof, to a signal processing unit, such as signal processing unit 702.

[0271] The ultrasonic waves directed at clamps 3604a, 3604b are reflected back to sensors 920a, 920b, enabling the generation of ultrasound images of clamps 3604a, 3604b andAtty Docket No. ABTEVA-0063PCT adjacent tissues. This capability allows for distance measurements between sensors 920a, 920b and clamps 3604a, 3604b to be obtained. Such distance measurements may further aid in determining whether or not tissue is captured between clamps 3604a, 3604b. Furthermore, the reflected waves can provide additional information regarding tissue within the clamps. For example, by analyzing the signal strength, frequency, and time-of- flight of the reflected waves, signal processing unit 702 can identify whether tissue is positioned within the clamps 3604a, 3604b to the desired depth and assess the thickness or density of the tissue. In the example depicted, each sensor 920a, 920b operates independently, allowing real-time imaging and feedback on tissue interaction. Such real-time imaging may be in the form of M-mode signals, for example.

[0272] Referring now in addition to FIG. 53, which depicts another exemplary implementation of sensors 920. In this example, a first sensor 920a’ and a second sensor 920b’ are movable relative to a catheter 3610’ of an interventional system 3600’ between a nested position (see sensor 920a’ in FIG. 53) and an extended position (see sensor 920b’ in FIG. 53). In the nested position, each sensor 920a’, 920b’ is docked within a main body 3612’ of catheter 3610’, providing a compact profile for navigation and deployment through the vasculature or other constrained anatomical pathways. Once catheter 3610’ is positioned at the target site (e.g., at a mitral valve or a tricuspid valve), sensors 920a’, 920b’ are independently or concurrently extended from main body 3612’ toward their respective clamps 3604a. 3604b and the target tissue (e.g., one or more valve leaflets). This extendable configuration may enable sensors 920a’, 920b’ to capture higher-resolution ultrasonic images by reducing the distance between each sensor 920a’, 920b’ and the area of interest. By being closer to clamps 3604a, 3604b, sensors 920a’, 920b’ may more accurately measure distances, detect tissue presence, and assess tissue properties, such as thickness or density.

[0273] 1'he movement of sensors 920a’, 920b’ between the nested and extended positions may be controlled via a mechanical mechanism integrated into interventional system. For example, a rigid wire or the like may be used to push and pull each respective sensor 920a’, 920b’ relative to catheter 3610’ . When the procedure is complete, sensors 920a’, 920b’ may be retracted into main body 3612’, ensuring a streamlined configuration for removal or repositioning.

[0274] Any one of the above-described exemplary implementations of sensing system 700 may be combined with any one of the other exemplary implementations. For example, theAtty Docket No. ABTEVA-0063PCT proximal element sensor arrangements of FIGS. 25-34 and 42-45 may be combined with any of the distal element sensor arrangements described with respect to FIGS. 35 and 46. Moreover, any of the center body and / or catheter sensor arrangements described with respect to FIGS. 36- 39 and 47-50 may be combined with the proximal element sensor arrangements of FIGS. 25- 34 and 42-45 and / or distal element arrangements of FIGS. 35 and 46. Furthermore, the piezoelectric ultrasonic sensor examples of FIGS. 51-53 may be utilized in conjunction with any of the proximal sensor arrangements of FIGS. 25-34 and 42-45 and / or distal element sensor arrangements of FIGS. 35 and 46.

[0275] According to the foregoing examples, piezoelectric sensing system 700 includes signal processing unit 702, one or more sensors 720, and an interface 708 between sensors 720 and signal processing unit 702. Sensors 720 may be any one or more of sensors 720’, 720”, 820, and 920. Thus, reference to sensors 720 in the following discussion includes any of such sensors 720’, 720”, 820, and 920. System 700 may include output device 710 for presenting discernable information from signal processing unit 702, aiding in surgeon decision-making.

[0276] In one exemplary implementation of piezoelectric sensing system 700, system 700 may be integrated into a fixation device, such as fixation device 1012, 2612, or 3612. In this regard, sensors 720 may be coupled to any one of the components thereof as described above. Additionally, signal processing unit 702 may also be coupled to any one of these fixation devices 1012, 2612, and 3612, such as to center portion 1060, 2660, 3660 thereof. In this example, signal processing unit 702 may process signals from each sensor 720 and then transmit an output signal to output device via a wireless protocol or via a hardwired connection through a delivery catheter (e.g., delivery catheter 1010, 2610, 3610), for example.

[0277] In another exemplary implementation of piezoelectric sensing system 700, sensors 720 may be coupled to a fixation device (e.g., fixation device 1012, 2612, or 3612) as described above and may communicate with signal processing unit 702 positioned external to the patient. Thus, in this example, a transmitter may be coupled to center portion (e.g., center portion 1060, 2660, or 3660) and may be configured to wirelessly transmit signals generated by sensors 720 to an extracorporeally located signal processing unit 702.

[0278] In a further exemplary implementation of piezoelectric sensing system 700, system 700 may be integrated with a medical system, such as the interventional system 3700 depicted in FIGS. 54-56B. Interventional system 3700 includes fixation device 3712 and a delivery system 3750. Fixation device 3712 may be any of fixation device 1012, 2612, andAtty Docket No. ABTEVA-0063PCT3612. Delivery system 3750 generally includes a delivery device handle 3751 and delivery catheter 3710 extending from handle 3751. Delivery catheter 3710 is representative of delivery catheters 1010, 2610, and 3610. Delivery device handle 3751 includes a plurality of controls 3753a, 3753b, 3753c for controlling fixation device 3712, such as proximal elements 3740 and distal elements 3720, and for disconnecting fixation device 3712 from a shaft 3711 of catheter 3710 so as to leave fixation device 3712 within a patient as an implant.

[0279] In one example, sensors 720 may be coupled to fixation device 3712 and / or catheter 3710 in accordance with any of the foregoing examples described above with respect to FIGS. 24-53. Additionally, signal processing unit 702 may be coupled to delivery handle 3751, such as embedded therein or separately connected (e.g., via a cable). In this example, interface 708 between signal processing unit 702 and sensors 720 may be a hardwired interface which may extend from implant 3712, through catheter 3710 to catheter handle 3751. For example, gripper lines 3701 may be comprised of insulating wiring which may extend through catheter 3710 and have the dual functions of providing an electrical connection between sensors 720 and control unit 702 and raising and lowering proximal elements 3740. Alternatively, electric conductors (e.g., leads or traces) may extend through catheter 3710 and into a center portion 3760 of fixation device 3712. When fixation device 3712 is disconnected from delivery catheter 3710 during a procedure, interface 708 between sensors 720 and control unit 702 may be disconnected and sensors 720 may be left within fixation device 3712 after disconnection between catheter 3710 and fixation device 3712.

[0280] As mentioned, signal processing unit 702 may be disposed in delivery device handle 3751. In this example, signal processing unit 702 may be coupled via a cable or otherwise to other external devices, such as output device 710. In another example, delivery device handle 3751 may include output device 710. For example, as shown in FIG. 54, such output device may be an LED array 3755 that turns on or off when any one of sensors 720 indicate has been captured by fixation device 3712.

[0281] In another example, signal processing unit 702 may be positioned external to delivery system 3700. In such example, signal processing unit 702 may be coupled to hardwiring within delivery system 3750 via a cable or otherwise so as to electrically couple signal processing unit with sensors 720.

[0282] FIGS. 51A and 5 IB depict one example of a disconnectable interface at a coupling 3715 (or coupler) between a delivery catheter 3710 and fixation device 3712. In thisAtty Docket No. ABTEVA-0063PCT example, delivery system 3750 includes an actuator rod 3770 like actuator rod 370 for actuating distal elements 3720. Delivery catheter 3710 includes a shaft 3711, like shaft 311, with two or more spring arms 3761 which are inwardly biased. Spring arms 3761 include projections or feet 3763 extending outwardly therefrom. Fixation device 3712 includes a coupling member 3760, like coupling member 360. Coupling member 3760 includes receptacles or apertures 3762 which are configured to receive projections 3763 for connection between shaft 3711 and coupling member 3760. As depicted, actuator rod 3770 extends distally through shaft 3711 and coupling member 3760 to urge spring arms 3761 outwardly which moves spring arms 3761 into engagement with coupling member 3760 and projections 3763 into receptacles 3762. Actuator rod 3770 is moveable proximally to a position proximal relative to spring arms 3761 which allows the bias of spring arms 3761 to move spring arms 3761 inwardly and disengage coupling member 3760 and thereby disconnect shaft 371 1 from fixation device 3712.

[0283] Shaft 3770 includes conductors 3703 (e.g., leads or traces) extending through catheter 3710 to delivery handle 3751 and which may be coupled to signal processing unit 702. Coupling member 3760 includes conductors 3709 (e.g., leads or traces) which extend through fixation device 3712 and are connected to sensors 720. Spring arms 3761 include electrical terminals or contact pads 3705 on an exterior thereof. Coupling member 3760 includes electrical terminals or contact pads 3707 on an interior thereof. Such terminals 3705, 3707 are connected to the respective conductors 3703, 3709 of shaft 3711 and coupling member 3760. When actuator rod 3770 moves distally within shaft 3711 and coupling member 3760, spring arms 3761 move outwardly such that terminals 3705 of shaft 371 1 contact terminals 3707 of coupling member 3760 thereby forming an electrical connection and electrically coupling signal processing unit 702 with sensors 720. When actuator rod 3770 moves proximally to disconnect shaft 3711 from coupling member 3760, spring arms 3761 move inwardly severing the electrical connection between terminals 3705, 3707 of shaft 3711 and coupling member 3760.

[0284] FIG. 57 illustrates an exemplary method 3800 according to the present disclosure. In the exemplary method 3800, a fixation device may be delivered 3802 to a target location within a patient. The fixation device may be any of the fixation devices described above (e.g., fixation device 1012, 2312, 2412, 2512, 2612, 3212, 3312, 3412, 3512, or 3612). The target location may be within a heart valve, such as a tricuspid valve or a mitral valve, for example. The method may also include directing 3804 a first tissue (or first leaflet) into a spaceAtty Docket No. ABTEVA-0063PCT between a first proximal element and a first distal element of a first clamp of the fixation device, and a second tissue (or a second leaflet) into a space between a second proximal element and a second distal element of a second clamp of the fixation device. The method may also include closing 3806 the first and second clamps by moving the first and second proximal elements towards the respect first and second distal elements, and measuring 3808 a response of a first piezoelectric sensor associated with the first clamp and a second piezoelectric sensor associated with the second clamp. The method may also include determining 3810 the presence or absence of tissue within the respective first and second clamps based on the measured response each of the first and second piezoelectric sensors.

[0285] In one example, the first and second piezoelectric sensors are pressure sensors, and the measured response of each of the first and second piezoelectric sensors is a direct mechanical pressure response based on mechanical pressure applied to the first piezoelectric sensor and the second piezoelectric sensor. The measured response is indicative of the presence of tissue at the location of the first piezoelectric sensor or the absence of tissue at the location of the first piezoelectric sensor. The measured response of the second piezoelectric sensor is a pressure response based on pressure applied to the second piezoelectric sensor and is indicative of the presence of tissue at the location of the second piezoelectric sensor or the absence of tissue at the location of the second piezoelectric sensor. Thus, the determining step 3810 can include determining a depth of tissue insertion within the respective first and second clamps. The method may also include correcting the measured response based on a measured blood pressure of the patient. Correcting the pressure response may include subtracting the measured blood pressure from the signal from each of the first and second piezoelectric sensors.

[0286] In another example, the first and second piezoelectric sensors are ultrasonic sensors, and the measured response of each of the first and second piezoelectric sensors is an acoustic pressure wave response based on reflected waves received by the first and second piezoelectric sensors. In one implementation, the measured response of each of the first and second piezoelectric sensors is an M-mode response providing real-time acoustic images of the respective first and second clamps and any tissue disposed therein. In this implementation the determining step 3810 may include observing the real-time acoustic images of the first and second clamps and assessing the presence or absence of tissue within the clamps.

[0287] Referring now to FIGS. 58A-62D, which depict further embodiments of piezoelectric sensing system 700 in which one or more piezoelectric sensors are coupled to aAtty Docket No. ABTEVA-0063PCT ring of a fixation device. The ring may be a radio-opaque ring (also referred to herein as an RO ring) positioned at a distal end of a delivery catheter shaft. The ring may be configured to receive a sensor package having one or more sensor arrays directed toward respective clamps of the fixation device. The sensor arrays may include one or more piezoelectric sensors configured to emit ultrasonic waves toward and receive reflected waves from tissue captured within the clamps of the fixation device. In this regard, the sensor arrays may have a collective width that is greater than a width of the proximal elements such that the sensor arrays may detect tissue extending beyond side edges of the proximal elements.

[0288] The ring may be connected to the delivery catheter shaft such that the ring rotates with the delivery catheter shaft. In this configuration, sensor arrays disposed on the sensor package may maintain a fixed rotational alignment with the proximal elements of the fixation device. The sensor package may include one or more sensor-bearing surfaces oriented to direct ultrasonic beams toward detection zones on the proximal elements. A sensor-bearing surface may be characterized by its curvature in two reference planes: a first plane parallel to a central axis of the sensor package, and a second plane perpendicular to the central axis of the sensor package. In some embodiments, the sensor package may include a sensor-bearing surface that is curved in both the first plane and the second plane. For example, a dome surface or a semi-spherical surface may be curved in both the first plane parallel to the central axis and the second plane perpendicular to the central axis. In other embodiments, the sensor package may include a sensor-bearing surface that is curved in the second plane perpendicular to the central axis but is not curved in the first plane parallel to the central axis. For example, a conical surface extending circumferentially about the central axis is curved in the second plane but has a linear profile in the first plane. In a further example, more than one conical sensor-bearing surface may be provided, such as two or more conical surfaces having different taper angles relative to the central axis. In still other embodiments, the sensor package may include one or more planar sensor-bearing surfaces that are not curved in either the first plane or the second plane. Such planar sensor-bearing surfaces may be angled relative to the central axis. The following sections describe various embodiments of the ring and sensor package in further detail.

[0289] Referring now to FIGS. 58A-58I, a delivery catheter may include a ring and a sensor package according to an embodiment of the present disclosure. As shown in FIG. 58A, a ring 4030 may include a sensor package 4050 disposed therein, and a fixation device 4012Atty Docket No. ABTEVA-0063PCT may be releasably coupled to a distal shaft 4010 of a delivery catheter (e.g., delivery catheter 3711 of FIG 54). It is noted that ring 4030 may have a circular cross-section but this is not required, and the ring 4030 may have an alternate uniform or non-uniform cross-sectional shape. In this embodiment, sensor package 4050 includes a sensor-bearing surface 4058 on which first and second sensor arrays 4070a, 4070b are disposed. The surface 4058 may have a non- planar configuration and may be curved in two planes: a first plane parallel to a central axis of sensor package 4050, and a second plane perpendicular to the central axis. In one example, surface 4058 is a dome surface that is curved in both the first and second planes. In another example, surface 4058 is a semi-spherical surface that is also curved in both the first and second planes. As best shown in FIG. 58B, first and second sensor arrays 4070a, 4070b may be disposed on opposite sides of delivery catheter shaft 4010 and may be aligned with respective clamps 4014a, 4014b of fixation device 4012 such that ultrasonic waves emitted by sensors 4072 in the arrays 4070a, 4070b are directed toward tissue captured within clamps 4014a, 4014b (only one sensor of the array is labeled for ease of illustration, however, it is to be understood that each array 4070a, 4070b includes a plurality of sensors as shown). Dome surface 4058 provides a continuous curved sensor-bearing surface that allows the sensor arrays 4070a, 4070b to be oriented toward clamps 4014a, 4014b of fixation device 4012. This dome configuration can orient sensors 4072 at multiple angles relative to fixation device 4012 to facilitate visualization over wide field of view.

[0290] Ring 4030 may be disposed at a distal end of delivery catheter shaft 4010 and may be releasably coupled to fixation device 4012. Ring 4030 may be a radio-opaque ring made from a stainless steel material, such as 304 SS, 316L, or 316LVM. As shown in FIG. 58A, ring 4030 may include a head 4034, a body 4032 extending proximally from head 4034, and a shaft 4036 extending proximally from body 4032. Head 4034 may have a larger diameter than body 4032, and body 4032 may have a larger diameter than shaft 4036. Shaft 4036 and body 4032 may be configured to couple to a delivery catheter (e.g., delivery catheter 3711). However, other configurations for coupling to the delivery catheter are contemplated. For example, in some embodiments, shaft 4036 may not be included, and body 4032 may be configured to as the only feature that couples directly to the delivery catheter.

[0291] Head 4034 may have an outer diameter sized to facilitate retraction of the fixation device 4012 into a steerable guide catheter. In one example, the outer diameter of head 4034 may be about 0.004 inches larger than a diameter of the guide catheter, such that ringAtty Docket No. ABTEVA-0063PCT4030 may guide the fixation device 4012 during retraction. In one example, the outer diameter of head 4034 may be about 0.212 inches.

[0292] Head 4034 may be configured to receive sensor package 4050. In this regard, head 4034 may include a cavity 4038 sized and shaped to receive sensor package 4050, as shown in FIG. 58C. Cavity 4038 is disposed at a distal side of head 4034 and opens in a distal direction. Head 4034 may also include a distal surface 4035 surrounding cavity 4038. As also shown in FIGS. 58C and 58D, cavity 4038 may include a planar inner surface 4048 and conical inner surface 4040 extending circumferentially about planar inner surface 4048. Conical inner surface 4040 may taper inwardly in a proximal direction and may be configured to interface with a corresponding conical surface on sensor package 4050 to assist with positioning sensor package 4050 within cavity 4038. In one example, the sensor package 4050 may be centered within cavity 4038.

[0293] As shown in FIG. 58C, ring 4030 may include a major lumen 4042 at a center thereof configured for passage of delivery catheter shaft 4010. Ring 4030 may also include a plurality of minor lumens arranged about major lumen 4042. In one example, ring 4030 may include four minor lumens 4044 for control lines, such as lock lines (e.g., lock line 102) or proximal element lines (e.g., proximal element line 101 a, 101b), arranged at 90-degree intervals about major lumen 4042. Ring 4030 may also include four minor lumens 4046 for sensor electrical wires arranged at 45-degree offsets from minor lumens 4044. Thus, ring 4030 may include a total of eight minor lumens arranged about major lumen 4042 at 45-degree intervals. However, more or fewer lumens are possible depending on sensor requirements and fixation device control requirements. In some embodiments, 1 to 8 electrical wires per quadrant may be routed through the minor lumens for the sensor arrays. The minor lumens 4046 for sensor wires may be positioned at locations between 0 degrees and 90 degrees within each quadrant, while certain positions, such as at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock, may be dedicated to fixation device control lines. Ring 4030 may be connected to the delivery catheter such that minor lumens 4044, 4046 of ring 4030 align with corresponding lumens in the delivery catheter.

[0294] Now referring to FIGS. 58G-58I, sensor package 4050 may be disposed within cavity 4038 of ring 4030 and may include one or more sensor-bearing surfaces 4058 on which sensor arrays 4070a, 4070b are disposed. Sensor package 4050 may be made from a ceramic material, an engineering polymer, or a flexible printed circuit board (PCB) material, forAtty Docket No. ABTEVA-0063PCT example. Sensor package 4050 may be coupled to ring 4030 via medical-grade adhesives, ultrasonic welding, or a press-fit connection. Flush mounting of sensor package 4050 within ring 4030 may be advantageous so that the sensors 4072 do not interfere with clip functions, such as opening and closing thereof.

[0295] As shown in FIG. 58G, sensor package 4050 may include a planar surface 4052 at a proximal side thereof configured to mate with a corresponding planar inner surface 4048 of ring 4030. Sensor package 4050 may optionally include a conical surface 4054 extending from planar surface 4052 and tapering outwardly in a distal direction. Conical surface 4054 may be configured to interface with conical inner surface 4040 of ring 4030 to assist with centering sensor package 4050 within cavity 4038. Sensor package 4050 may further include a cylindrical surface 4056 extending distally from conical surface 4054 for further mating with head 4034 within cavity 4038.

[0296] Sensor package 4050 may include a dome surface 4058 extending distally from cylindrical surface 4056, as best shown in FIG. 58G. Dome surface 4058 may provide a sensorbearing surface on which sensor arrays 4070a, 4070b are disposed. Dome surface 4058 may have a radius of curvature in a range of about 0.05 inches to about 0.15 inches. In one example, the radius of curvature may be in a range of about 0.08 inches to about 0.12 inches.

[0297] The curvature of dome surface 4058 may cause sensors 4072 disposed at different locations on dome surface 4058 to direct ultrasonic beams at different angles toward clamps 4014a, 4014b of fixation device 4012. Sensors 4072 disposed at a central region of dome surface 4058 (i.e., closer to a central axis of sensor package 4050) may direct beams more directly distally, whereas sensors 4072 disposed at peripheral regions of dome surface 4058 (i.e., further from the central axis) may direct beams at angles that are more outwardly directed toward the respective clamps 4014a, 4014b. This may allow sensor arrays 4070a, 4070b disposed on dome surface 4058 to cover a range of detection angles allowing visualization of leaflet capture between open and closed positions of fixation device 4012.

[0298] The curvature of dome surface 4058 may also allow sensors 4072 to be disposed at different heights relative to ring 4030. Sensors 4072 disposed at a more proximal location on dome surface 4058 may be at a different height than sensors 4072 disposed at a more distal location on dome surface 4058. This height differential may affect the angle at which ultrasonic beams are directed toward clamps 4014a, 4014b. The sensor package 4050 is disposed within cavity 4038 of ring 4030 such that the sensor-bearing dome surface 4058 extends distally fromAtty Docket No. ABTEVA-0063PCT ring head 4034 while the mating surfaces (planar surface 4052, conical surface 4054) are seated within the cavity. This configuration positions sensor package 4050 clear of clip arm movement paths while providing sensor arrays 4070a, 4070b with an unobstructed line of sight toward proximal elements 4016a, 4016b. Additionally, this arrangement may offer options for mounting arrayed sensors 4072 at various heights on the dome surface 4058, which may allow sensor package 4050 to direct beams toward multiple detection zones on proximal elements 4016a, 4016b.

[0299] Sensor package 4050 includes a central opening 4060 extending therethrough for passage of delivery catheter shaft 4010, as shown in FIGS. 58G and 58H. Central opening 4060 is coaxial with major lumen 4042 of ring 4030 when sensor package 4050 is disposed therein. Sensor package 4050 may also include a plurality of peripheral openings 4062 configured to align with minor lumens 4044 of ring 4030 for passage of fixation control lines (e.g., proximal element lines and lock lines). As shown in FIG. 58H, openings 4062 may be arranged about and optionally interconnected to central opening 4060.

[0300] In the example depicted, sensor package 4050 may include a first sensor array 4070a and a second sensor array 4070b disposed on dome surface 4058, as shown in FIGS. 58B, 58H, and 581. First and second sensor arrays 4070a, 4070b may be disposed on opposite sides of delivery catheter shaft 4010 and may be aligned with respective clamps 4014a, 4014b of fixation device 4012. In this configuration, first sensor array 4070a may be directed toward a first clamp 4014a, and second sensor array 4070b may be directed toward a second clamp 4014b. The sensor arrays 4070a, 4070b may be configured such that ultrasonic waves emitted by sensors 4072 in the arrays are directed toward tissue captured within clamps 4014a, 4014b when the clamps are in an open position (e.g., at 120 degrees) relative to each other.

[0301] As used herein, the term "sensor array" refers to a discrete group of two or more sensors arranged in a defined spatial pattern on a sensor-bearing surface. In some examples, the sensors within a sensor array may be equally spaced from one another. In other examples, the sensors within a sensor array may be arranged in a rectangular pattern, a circular pattern, a linear pattern, or other geometric arrangement. Each sensor array is spatially separated from other sensor arrays on the sensor-bearing surface.

[0302] As shown in FIG. 581, first sensor array 4070a may be disposed on dome surface 4058 and may be directed toward first clamp 4014a of fixation device 4012. First sensor array 4070a may include a plurality of sensors 4072 arranged in a pattern, such as a rectangularAtty Docket No. ABTEVA-0063PCT pattern with a long dimension extending outwardly away from delivery catheter shaft 4010 at opposite sides thereof. First sensor array 4070a may surround or be disposed adjacent to an opening 4062 for a control line associated with first clamp 4014a. Second sensor array 4070b may be disposed on dome surface 4058 opposite first sensor array 4070a and may be directed toward second clamp 4014b of fixation device 4012. Second sensor array 4070b may be configured similarly to first sensor array 4070a. While the example depicted includes a rectangular-shape array, other sensor array patterns are contemplated, such as circular patterns or other geometric arrangements.

[0303] Each sensor array 4070a, 4070b may include a plurality of individual sensors 4072. Sensors 4072 may be piezoelectric sensors, such as piezoelectric micromachined ultrasonic transducers (PMUTs). PMUTs may utilize a thin piezoelectric layer on a micromachined diaphragm placed over a silicon substrate. PMUTs may operate in a frequency range of about 1 MHz to about 10 MHz and may provide a miniaturized sensor suitable for the spatial constraints of sensor package 4050. PMUTs may be advantageous for their miniaturized size, scalability, and compatibility with semiconductor manufacturing processes that are repeatable and reproducible. Each sensor array may include 1 to 25 sensors 4072. Thus, sensor package 4050 may include a total of 2 to 50 sensors across first and second sensor arrays 4070a, 4070b. In other embodiments, sensors 4072 may be lead zirconate titanate (PZT) sensors.

[0304] PMUT and PZT sensors are both based on piezoelectric principles, but they have different structures, fabrication methods, and operating characteristics. PMUT sensors utilize thin-film piezoelectric materials integrated on silicon substrates, whereas PZT sensors utilize bulk ceramic materials. The MEMS-based configuration of PMUT sensors enables miniaturization and integration with semiconductor processes, whereas PZT sensors are generally larger in size and less compatible with CMOS processes. PMUT sensors may be manufactured using semiconductor processes that allow wafer-level batch production, whereas PZT sensors are typically manufactured by sintering and machining of ceramics.

[0305] PMUT and PZT sensors also differ in their operating principles. PMUT sensors operate in a diaphragm mode in which the piezoelectric element bends or flexes rather than expanding and contracting uniformly. PZT sensors operate in a thickness mode in which the piezoelectric element expands and contracts. PMUT sensors may operate in a frequency range of about 1 MHz to about 10 MHz, whereas PZT sensors may operate in a frequency range from kHz to tens of MHz.Atty Docket No. ABTEVA-0063PCT

[0306] PMUT sensors are applicable for sensors 4072 of sensor package 4050 because they offer a miniaturized size suitable for the spatial constraints of sensor package 4050 and can be arranged in arrays on small silicon substrates. For example, up to 25 PMUT sensors may be arranged on a small silicon substrate for each of sensor arrays 4070a, 4070b. The semiconductor manufacturing processes used to fabricate PMUT sensors may be repeatable and reproducible, which are advantageous for transcatheter applications. However, PZT sensors may also be utilized for sensors 4072. Both PMUT and PZT sensors may be configured to emit ultrasonic waves toward tissue captured within clamps 4014a, 4014b of fixation device 4012 and receive reflected waves therefrom to detect the presence and extent of tissue within fixation device 4012.

[0307] As described above, sensor package 4050 is disposed within cavity 4038 at the distal end of ring 4030. Referring now to FIGS. 58E and 58F, which illustrate a standoff distances between ring 4030 and fixation devices of different sizes. Standoff distance may be defined between free ends of distal elements and distal surface 4035 of head 4034 when the fixation device is in a closed position such that the clamps are at their highest point (i.e., zenith) relative to ring 4030. Having a suitable standoff distance provides clearance such that the fixation device may open and close freely without interference from sensor package 4050. The standoff distance may vary depending on the clamp length of the fixation device, as discussed below.

[0308] Referring now to FIG. 58E, ring 4030 and sensor package 4050 may be used with a first fixation device 4112. First fixation device 4112 includes first and second clamps 4114a, 4114b each defining a first clamp length El. Such clamp length LI may be about 9mm, for example. In such example, the first standoff distance DI between distal surface 4035 of head 4034 and free ends 4119 of clamps 4114a, 4114b may be about 0.23 inches, or about 5.8mm. In some embodiments, the first standoff distance DI may be within a range of plus or minus 5% of these values.

[0309] Referring now to FIG. 58F, ring 4030 and sensor package 4050 may be used with a second fixation device 4212 having a second clamp length L2 which is greater than LI. For example, second clamp length L2 may be about 12mm. In such example, the second standoff distance D2 between distal surface 4035 of head 4034 and free ends 4219 of clamps 4214a, 4214b may be about 0.146 inches, or about 3.7mm. In some embodiments, the second standoff distance DI may be within a range of plus or minus 5% of these values.Atty Docket No. ABTEVA-0063PCT

[0310] Electrical wires from sensors 4072 may be routed through minor lumens 4046 of ring 4030 and through delivery catheter shaft 4010 to a signal processing unit, such as signal processing unit 702, as discussed further below. Sensors 4072 may be pre-mounted on sensor package 4050 with electrical wires that may be bonded, welded, or pressed onto sensor package 4050. In some embodiments, 1 to 8 wires per quadrant may be routed for the sensor arrays 4070a, 4070b.

[0311] As shown in FIG. 581, sensor package 4050 may be disposed within cavity 4038 of head 4034 such that planar surface 4052 mates with a planar inner surface 4048 of ring 4030, conical surface 4054 optionally interfaces with conical inner surface 4040 for centering, and dome surface 4058 is exposed at a distal side of ring 4030. Delivery catheter shaft 4010 extends through major lumen 4042, central opening 4060, and so that delivery catheter shaft 4010 can releasably couple to a coupling member 4024 of fixation device 4012. Ring 4030 rotates with delivery catheter shaft 4010 such that first and second sensor arrays 4070a, 4070b maintain alignment with first and second clamps 4014a, 4014b, respectively.

[0312] Referring now to FIGS. 59A and 59B, a ring may include a sensor package according to another embodiment of the present disclosure. As shown in the bottom perspective view of FIG. 59A, a ring 4330 may include a head 4334, a body 4332 extending proximally from head 4334, and a shaft 4336 extending proximally from body 4332. Ring 4330 may be similar to ring 4030 described above with respect to FIGS. 58A-58I. A sensor package 4350 may be similarly disposed in head 4334 of ring 4330. Sensor package 4350 also includes a dome surface 4358.

[0313] However, sensor package 4350 differs from sensor package 4050 in that sensor package 4350 includes four sensor arrays 4370a, 4370b, 4370c, 4370d arranged in quadrants on dome surface 4358. First sensor array 4370a and second sensor array 4370b may be directed toward a first clamp, and third sensor array 4370c and fourth sensor array 4370d may be directed toward a second clamp. Each sensor array 4370a, 4370b, 4370c, 4370d may include one or more sensors 4372, such as piezoelectric sensors (only a few sensors 4372 are referenced for ease of illustration). In one example, each sensor array may include one to twenty-five sensors 4372 arranged in a plurality of rows, for example, in a rectangular pattern. However, other array patterns are possible, such as circular patterns or other geometric configurations.

[0314] As also shown in FIG. 59A, sensor package 4370 may include openings 4362 for control lines (such as lock lines and proximal element lines) and for passage of a catheterAtty Docket No. ABTEVA-0063PCT shaft, such as delivery catheter shaft 4310. In the depicted example, openings 4362 may intersect to form a single opening (e.g., the non-limiting example of FIG. 59A includes an opening 4362 having a plus-shape). However, in other examples, discrete openings may be provided for each control line and for the catheter shaft.

[0315] FIG. 59B illustrates the relationship of sensor arrays 4370a-4370d relative to a gripping device 4380 of an exemplary fixation device that includes first and second proximal elements 4382a, 4382b. A shown, first and second planes Pl, P2 are arranged orthogonal to each other and each bisect ring 4330 and sensor package 4350. Additionally, second plane P2 extends along a length of first and second proximal elements 4382a, 4382b and bisects their respective width Wl. In this regard, first and second planes PI, P2 divide dome surface 4358 into four quadrants, with each quadrant including a respective sensor array 4370a, 4370b, 4370c, 4370d. As shown, first sensor array 4370a is positioned at a first side of second plane P2 and is directed toward first proximal element 4382a. Second sensor array 4370b is positioned at a second, opposite side of second plane P2 and is also directed toward first proximal element 4382a. Third sensor array 4370c is positioned at the first side of second plane P2 and is directed toward second proximal element 4382b. Fourth sensor array 4370d is positioned at the second side of second plane P2 and is also be directed toward second proximal element 4382b.

[0316] As further shown in FIG. 59B, first and second proximal elements 4382a, 4382b each have a first width Wl defined between side edges 4384 thereof. First and second sensor arrays 4370a, 4370b have a collective second width W2, and third and fourth sensor arrays 4370c, 4370d also have a collective second width W2. As various examples of the disclosure include sensor arrays having a variable width that may or may not correspond to the shape of the dome surface 4358, widths Wl and W2 are a maximum measurement as measured parallel to first plane Pl and perpendicular to second plane P2. Second width W2 is greater than first width Wl such that sensor arrays 4370a, 4370b, 4370c, 4370d extend beyond one or more side edges 4384 of proximal elements 4382a, 4382b. This width relationship facilitates directing ultrasonic beams toward and beyond the side edges 4384 of proximal elements 4382a, 4382b to define the width component of the detection zone, which assists in assessing the adequacy of tissue capture. It should be noted that this width relationship may be applicable to all of the sensor array and sensor package examples described herein.Atty Docket No. ABTEVA-0063PCT

[0317] A space 4390 may be provided between first sensor array 4370a and second sensor array 4370b along which a portion of first proximal element 4382a may extend. In other words, the first sensor array 4370a may be separated from the second sensor array 4370b by space 4390 having a length equal to or greater than Wl . Similarly, a space 4392 may be provided between third sensor array 4370c and fourth sensor array 4370d along which a portion of second proximal element 4382b may extend. In other words, the third sensor array 4370c may be separated from the fourth sensor array 4370d by space 4392 having a length equal to or greater than Wl. This configuration may reduce complexity and cost by omitting sensors in regions where the solid metal structure of proximal elements 4382a, 4382b would otherwise block ultrasonic beams from the sensors 4372. Because the proximal elements 4382a, 4382b are formed from solid metal, ultrasonic beams directed at the proximal elements would be blocked rather than passing through to detect tissue. Accordingly, the spaces between sensor arrays correspond to regions where the proximal elements 4382a, 4382b are located, and the sensor arrays themselves are positioned to direct beams toward the side edges 4384 of the proximal elements 4382a, 4382b.

[0318] Sensor arrays 4370a, 4370b, 4370c, 4370d disposed on sensor package 4350 may be configured to direct ultrasonic beams toward specific detection zones on proximal elements 4382a, 4382b of gripping device 4380. A detection zone may be defined as a region where the sensor arrays 4370a, 4370b, 4370c, 4370d are configured to observe tissue. A detection zone may have a width component and a length component defined by the direction in which the ultrasonic beams are emitted from the sensor arrays 4370a, 4370b, 4370c, 4370d. The width component and the length component may be a function of the dimensions of the sensor arrays 4370a, 4370b, 4370c, 4370d and the angles at which the sensors 4372 are oriented, which may be a function of the geometry of the sensor-bearing surface (e.g., dome surface 4358). Because ultrasonic beams do not pass through the solid metal structure of the proximal elements 4382a, 4382b, the detection zone is focused at and / or adjacent to the side edges 4384 where tissue can be detected without obstruction from the gripper structure. The width component is defined as the extent to which the detection zone extends transversely beyond the side edges 4384 of the proximal element 4382a, 4382b, and may be expressed as a percentage of the proximal element width Wl. A collective width component refers to the combined extent to which the detection zone extends beyond both side edges 4384 of a proximal element 4382a, 4382b. In one example, the collective width component may extendAtty Docket No. ABTEVA-0063PCT beyond the side edges 4384 by a total distance corresponding to about 50% of the proximal element width W 1. In other examples, the collective width component may extend beyond the side edges 4384 by a total distance corresponding to about 25% to about 75% of the proximal element width Wl . The length component is defined relative to the length of the proximal element 4382a, 4382b. In some examples, the length component may extend along the entire length of the proximal element 4382a, 4382b. In other examples, the length component may extend along less than the entire length of the proximal element 4382a, 4382b. For example, the length component may overlap with 50% of the length of the proximal element 4382a, 4382b as measured from the free end thereof. In other examples, the length component may overlap with 25% of the proximal element length as measured from the free end, or 75% of the proximal element length as measured from the free end. Assessing tissue presence along the length component allows tissue insertion depth to be evaluated to ensure tissue is properly grasped within the gripper to prevent leaflet detachment.

[0319] A single sensor 4372 or a phased array of sensors 4372 may transmit signals that are directed toward both side edges 4384 of the proximal element 4382a, 4382b to detect the presence of tissue or leaflets extending beyond the proximal element 4382a, 4382b. As described above, the detection zone is focused at and / or adjacent to the side edges 4384 because ultrasonic beams do not pass through the solid metal structure of the proximal elements 4382a, 4382b. The width component of the detection zone may thus extend beyond side edges 4384 of proximal elements 4382a, 4382b to encompass regions where captured tissue may be present.

[0320] The length component of the detection zone may extend along the length of proximal elements 4382a, 4382b. As described above, sensor arrays 4370a, 4370b, 4370c, 4370d may be arranged in rectangular patterns. This arrangement may allow sensor arrays 4370a, 4370b, 4370c, 4370d to detect tissue along the length of each proximal element 4382a, 4382b, which may provide information regarding the depth of tissue insertion within the clamp. As described with respect to FIGS. 20A and 20B, tissue insertion to at least 50% of the grip length Lgrip may be associated with sufficient pinch force for secure tissue capture and reduced risk of single leaflet device attachment (SLDA). The sensor arrays 4370a, 4370b, 4370c, 4370d may be configured to detect tissue presence at or beyond this depth threshold, thereby confirming clinically adequate tissue insertion. If tissue is present in the detection zone, anAtty Docket No. ABTEVA-0063PCT output signal from sensors 4372 may change accordingly. If no tissue is present in the detection zone, the output signal may remain unchanged.

[0321] The quadrant arrangement of sensor arrays 4370a, 4370b, 4370c, 4370d may provide several benefits. By positioning two sensor arrays toward each clamp, sensor package 4350 may detect tissue at multiple locations along the length of each proximal element 4382a, 4382b. This may provide more detailed information regarding the position and extent of tissue captured within each clamp. Additionally, the arrangement of sensor arrays 4370a, 4370b, 4370c, 4370d at opposite sides of each proximal element 4382a, 4382b may allow detection of tissue extending beyond side edges 4384 of the proximal elements 4382a, 4382b, which may assist in assessing whether tissue has been adequately captured.

[0322] Referring now to FIG. 60, which depicts a ring 4430 and a sensor package 4450 according to another embodiment of the present disclosure. It is noted that ring 4030 may have a circular cross-section but this is not required and the ring 4030 may have an alternative uniform or non-uniform cross-sectional shape. Ring 4430 is similar to ring 4030 except as explicitly stated. Additionally, sensor package 4450 is similar to sensor package 4050 described above in that it is disposed in a cavity of head 4434, includes a central opening for passage of a catheter shaft, and includes openings for control lines. However, unlike sensor package 4050, sensor package 4450 includes conical sensor-bearing surfaces 4452, 4454.

[0323] Ring 4430 may include a head 4434, a body 4432 extending proximally from head 4434, and a shaft 4436 extending proximally from body 4432. Head 4434 may have a larger diameter than body 4432, and body 4432 may have a larger diameter than shaft 4436. A delivery catheter shaft 4410 may extend through ring 4430 and may be releasably coupled to a fixation device 4412. Fixation device 4412 may include a coupling member 4424, a first clamp 4414a, and a second clamp 4414b. First clamp 4414a may include a first proximal element 4416a and a first distal element 4418a. Second clamp 4414b may include a second proximal element 4416b and a second distal element 4418b. Fixation device 4412 may be similar to fixation device 112 described above.

[0324] Sensor package 4450 may be disposed in head 4434 of ring 4430. As mentioned above, sensor package 4450 may include conical sensor-bearing surfaces rather than a dome surface. Unlike the dome surface which is curved in both a first plane parallel to the central axis and a second plane perpendicular to the central axis, the conical sensor-bearing surfaces 4558, 4560 are curved in the second plane perpendicular to the central axis A but have a linearAtty Docket No. ABTEVA-0063PCT profile in the first plane parallel to the central axis. In this regard, sensor package 4450 may include a first conical surface 4452 and a second conical surface 4454. First and second conical surfaces 4452, 4454 may each extend circumferentially about center axis A of sensor package 4450 and may each taper in a distal direction toward center axis A. The intersection of first and second conical surfaces 4452, 4454 may form a pyramid-type structure extending distally from ring 4430.

[0325] Sensor package 4450 may include first conical surface 4452 and second conical surface 4454, each extending circumferentially about a center axis of sensor package 4450. First conical surface 4452 may extend from an outer edge of sensor package 4450 and taper in a distal direction toward the center axis at a first taper angle. Second conical surface 4454 may extend from first conical surface 4452 and taper in a distal direction toward the center axis at a second taper angle. The first taper angle may be steeper than the second taper angle.

[0326] The differing taper angles of first conical surface 4452 and second conical surface 4454 may direct ultrasonic beams at different angles toward clamps 4414a, 4414b of fixation device 4412. Sensors 4472 disposed on first conical surface 4452 may direct beams at a first angle corresponding to the steeper first taper angle, and sensors 4472 disposed on second conical surface 4454 may direct beams at a second angle corresponding to the shallower second taper angle.

[0327] In addition to the axial beam angles provided by the differing taper angles, the circumferential curvature of first conical surface 4452 and second conical surface 4454 may orient sensors 4472 disposed thereon at diverging angles in a plane perpendicular to the center axis of sensor package 4450. This circumferential curvature may expand the width component of the detection zone beyond the physical footprint of the sensor arrays 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, enabling detection of tissue extending laterally beyond the side edges of proximal elements 4416a, 4416b.

[0328] This dual-angle configuration may allow sensor package 4450 to detect tissue at various clamp positions between open and closed configurations. For example, the shallower angle of second conical surface 4454 may be suited for detecting tissue when clamps 4414a, 4414b are in a more open position (about 120 degrees between clamps 4414a, 4414b), while the steeper angle of second conical surface 4452 may be suited for detecting tissue when clamps 4414a, 4414b are in a more closed position (e.g., 10-60 degrees between clamps 4414a, 4414b). Additionally, the dual-angle configuration may enable detection of tissue at different locationsAtty Docket No. ABTEVA-0063PCT along the length of proximal elements 4416a, 4416b. This multi-angle detection capability may be beneficial for detecting leaflet insertion and monitoring for potential leaflet slippage during a TEER procedure.

[0329] In the example depicted in FIG. 60, sensor package 4450 includes a plurality of sensor arrays 4470a, 4470b, 4470c, 4470d, 4470e, 4470f distributed across first and second conical sensor-bearing surfaces 4452, 4454. In one example, the sensor package 4450 includes two or more arrays 4470a-f. Each sensor array 4470a, 4470b, 4470c, 4470d, 4470e, 4470f may include one or more sensors 4472, such as piezoelectric sensors as described above. In one example, each sensor array may include one to twenty-five sensors 4472. The sensors 4472 in each array may be arranged in a rectangular pattern. However, other array patterns are possible, such as circular patterns or other configurations.

[0330] The six sensor arrays 4470a, 4470b, 4470c. 4470d, 4470e, 4470f may be arranged such that three sensor arrays are directed toward each clamp 4414a, 4414b of fixation device 4412. First sensor array 4470a, second sensor array 4470b, and third sensor array 4470c may be directed toward first clamp 4414a and first proximal element 4416a thereof. Fourth sensor array 4470d, fifth sensor array 4470e, and sixth sensor array 4470f may be directed toward second clamp 4414b and second proximal element 4416b thereof. This arrangement may provide enhanced coverage of each clamp 4414a, 4414b by distributing sensors across both conical surfaces 4452, 4454.

[0331] First sensor array 4470a may be disposed on first conical surface 4452 and may have a rectangular shape with a long dimension extending perpendicular to a width of first clamp 4414a. Second sensor array 4470b and third sensor array 4470c may be disposed on second conical surface 4454 and may also extend lengthwise perpendicular relative to first clamp 4414a. Second sensor array 4470b and third sensor array 4470c may be separated by an opening passing through sensor package 4450 for a control line, such as a proximal element line that controls first proximal element 4416a.

[0332] Fourth sensor array 4470d, fifth sensor array 447 Oe, and sixth sensor array 4470f may be arranged in a similar manner relative to second clamp 4414b. Fourth sensor array 4470d may be disposed on first conical surface 4452 and may have a rectangular shape with a long dimension extending perpendicular to a width of second clamp 4414b. Fifth sensor array 4470e and sixth sensor array 4470f may be disposed on second conical surface 4454 and may also extend lengthwise perpendicular relative to second clamp 4414b. Fifth sensor array 4470eAtty Docket No. ABTEVA-0063PCT and sixth sensor array 4470f may be separated by an opening passing through sensor package 4450 for a control line, such as a proximal element line that controls second proximal element 4416b.

[0333] Sensor package 4450 may be disposed in head 4434 of ring 4430 such that first and second conical surfaces 4452, 4454 face distally toward fixation device 4412. The sensor arrays 4470a, 4470b, 4470c disposed on first and second conical surfaces 4452, 4454 may be aligned with first clamp 4414a such that ultrasonic waves emitted by sensors 4472 therein are directed toward first proximal element 4416a. Similarly, the sensor arrays 4470d, 4470e, 4470f disposed on first and second conical surfaces 4452, 4454 may be aligned with second clamp 4414b such that ultrasonic waves emitted by sensors 4472 therein are directed toward second proximal element 4416b. Because ring 4430 rotates with the delivery catheter shaft 4410, the sensor arrays 4470a, 4470b, 4470c, 4470d, 4470e, 4470f may remain aligned with their respective clamps 4414a, 4414b during rotation of delivery catheter shaft 4410.

[0334] Referring now to FIGS. 61A-61C, which depict a ring 4530 and a sensor package 4550 according to another embodiment of the present disclosure. Ring 4530 is similar to ring 4030 in that it includes a body 4532, head 4534, and shaft 4536. Sensor package 4550 is similar to sensor package 4450 described above with respect to FIG. 60 in that it includes conical sensor-bearing surfaces 4558, 4560 and is disposed in a cavity of the ring head 4534. However, unlike sensor package 4450, sensor package 4550 exemplifies a differing sensor array arrangement. In this regard, sensor package 4550 includes four sensor arrays 4570a- 4570d, and each sensor array spans from the first conical surface 4558 to the second conical surface 4560.

[0335] As shown in FIGS. 61 A and 61B, sensor package 4550 may be disposed in head4534 of ring 4530. In this regard, sensor package 4550 may include one or more mating surfaces extending from a proximal side to a distal side thereof. For example, at a proximal side of sensor package 4550, a planar surface 4552 may be provided for mating with a planar inner surface of ring 4530. Extending distally from planar surface 4552, a conical surface 4554 may be provided for mating with an inner conical surface of ring 4530, which may assist in centering sensor package 4550 within head 4534 of ring 4530. Additionally, a cylindrical surface 4556 may extend distally from conical surface 4554.

[0336] Sensor package 4550 also includes two or more conical sensor-bearing surfaces.For example, sensor package 4550 includes a first conical surface 4558 extending distally fromAtty Docket No. ABTEVA-0063PCT cylindrical surface 4556 which tapers in a distal direction toward a central axis A of sensor package 4550 at a first taper angle. First conical surface 4558 may be an outer conical surface and may extend circumferentially about central axis A.

[0337] Additionally, sensor package 4550 may include a second conical surface 4560 extending distally from first conical surface 4558 and may taper in a distal direction toward central axis A at a second taper angle. Second conical surface 4560 may be an inner conical surface and may extend circumferentially about central axis A. As with sensor package 4450, the first taper angle of first conical surface 4558 may be steeper than the second taper angle of second conical surface 4560.

[0338] As shown in FIG. 61A, central axis A of sensor package 4550 may be coaxial with central opening 4562 for passage of a catheter shaft. A first angle a may be measured from central axis A to first conical surface 4558. First angle a may be in a range of about 195 degrees to about 215 degrees from central axis A (or about 23 degrees to about 27 degrees from a horizontal plane perpendicular to central axis A). A second angle P may be measured from central axis A to second conical surface 4560. Second angle may be in a range of about 95 degrees to about 105 degrees from central axis A (or about 9 degrees to about 11 degrees from the horizontal plane perpendicular to central axis A).

[0339] The angular relationships of first and second conical surfaces 4558, 4560 may be beneficial for detecting leaflet insertion and potential leaflet slippage during a TEER procedure. The shallower angle P of second conical surface 4560 may direct ultrasonic waves at an angle suited for detecting tissue when clamps are in a more open position, while the steeper angle a of first conical surface 4558 may direct ultrasonic waves at an angle suited for detecting tissue when clamps are in a more closed position. Additionally, the different angles may enable detection of tissue at different locations along the length of proximal elements 4582a, 4582b. By detecting tissue across a range of clamp positions and locations, sensor package 4550 may provide information regarding both the initial insertion of a leaflet and any subsequent slippage of the leaflet during the procedure.

[0340] Sensor package 4550 may include four sensor arrays 4570a, 4570b, 4570c, 4570d. Each sensor array 4570a, 4570b, 4570c, 4570d may include one or more sensors 4572, such as piezoelectric sensors. In one example, each sensor array may include one to twenty- five sensors 4572. The sensors 4572 in each array may be arranged in a rectangular pattern. However, other array patterns are possible, such as circular patterns or other configurations.Atty Docket No. ABTEVA-0063PCT

[0341] Unlike sensor package 4450 of FIG. 60, in which six sensor arrays are distributed across the two conical surfaces with each array disposed on only one conical surface, sensor package 4550 includes four sensor arrays that each span from first conical surface 4558 to second conical surface 4560. This spanning arrangement may allow each sensor array 4570a, 4570b, 4570c, 4570d to detect tissue at multiple angles corresponding to both conical surfaces 4558, 4560. It may also maximize the number of sensors positioned on package 4450 and provide uninterrupted monitoring along the span of each array.

[0342] As shown in FIG. 6 IB, openings 4564 for control lines and the catheter shaft may be arranged in a plus-shape, essentially dividing the sensor arrays 4570a, 4570b, 4570c, 4570d into quadrants. First and second sensor arrays 4570a, 4570b may be directed toward a first clamp, and third and fourth sensor arrays 4570c, 4570d may be directed toward a second clamp.

[0343] First sensor array 4570a and second sensor array 4570b may each extend from first conical surface 4558 to second conical surface 4560 and may be directed toward a first clamp of a fixation device. First and second sensor arrays 4570a, 4570b may be offset from each other so as to form a space 4590 therebetween, as best shown in FIG. 61B. This space 4590 may correspond to a region along which a portion of a first proximal element 4582a extends. First and second sensor arrays 4570a, 4570b may each be arranged in a rectangular pattern with the length of the rectangular array extending parallel to a length of first proximal element 4582a.

[0344] Third sensor array 4570c and fourth sensor array 4570d may each extend from first conical surface 4558 to second conical surface 4560 and may be directed toward a second clamp of the fixation device. Third and fourth sensor arrays 4570c, 4570d may be arranged in a similar manner to first and second sensor arrays 4570a, 4570b, but on an opposite side of central axis A. Third and fourth sensor arrays 4570c, 4570d may be offset from each other so as to form a space 4592 therebetween, as best shown in FIG. 61B. This space 4592 may correspond to a region along which a portion of a second proximal element 4582b extends. Third and fourth sensor arrays 4570c, 4570d may each be arranged in a rectangular pattern with the length of the rectangular array extending parallel to a length of second proximal element 4582b.

[0345] Referring now to FIG. 61C, which depicts the relationship of sensor arrays 4570a, 4570b, 4570c, 4570d relative to a gripping device 4580 that includes first and secondAtty Docket No. ABTEVA-0063PCT proximal elements 4582a, 4582b. First and second planes Pl, P2 are shown in relation to ring 4530 and sensor package 4550. First plane Pl and second plane P2 are orthogonal and each bisect ring 4530 and sensor package 4550. Second plane P2 extends along a length of first and second proximal elements 4582a, 4582b and bisect their respective widths Wl . First and second planes Pl, P2 divide the sensor arrays 4570a, 4570b, 4570c, 4570d into quadrants.

[0346] First and second proximal elements 4582a, 4582b each have a first width Wl defined between side edges 4584 thereof. First and second sensor arrays 4570a, 4570b have a collective second width W2, and third and fourth sensor arrays 4570c, 4570d also have a collective second width W2. Widths Wl and W2 are measured parallel to first plane Pl and perpendicular to second plane P2. Second width W2 is greater than first width Wl such that sensor arrays 4570a, 4570b, 4570c, 4570d extend beyond side edges 4584 of proximal elements 4582a, 4582b. This width relationship facilitates directing ultrasonic beams toward and beyond the side edges 4584 of proximal elements 4582a, 4582b to define the width component of the detection zone, which may assist in assessing the adequacy of tissue capture.

[0347] Sensor package 4550 may be disposed in head 4534 of ring 4530 such that planar surface 4552 mates with a planar inner surface of ring 4530 and conical surface 4554 mates with an inner conical surface of ring 4530 for centering. First and second conical surfaces 4558, 4560 may face distally toward a fixation device. The sensor arrays 4570a, 4570b disposed on first and second conical surfaces 4558, 4560 may be aligned with a first clamp such that ultrasonic waves emitted by sensors 4572 therein are directed toward first proximal element 4582a. Similarly, the sensor arrays 4570c, 4570d disposed on first and second conical surfaces 4558, 4560 may be aligned with a second clamp such that ultrasonic waves emitted by sensors 4572 therein are directed toward second proximal element 4582b.

[0348] The four-array spanning configuration of sensor package 4550 may provide several benefits. By having each sensor array 4570a, 4570b, 4570c, 4570d span from first conical surface 4558 to second conical surface 4560, each array may detect tissue at multiple angles corresponding to both conical surfaces. This may provide comprehensive information regarding the position and extent of tissue captured within each clamp. The spanning arrangement may also simplify manufacturing and reduce the total number of sensor arrays compared to sensor package 4450 of FIG. 60 while still providing multi-angle detection capability.Atty Docket No. ABTEVA-0063PCT

[0349] Referring now to FIGS. 62A-62D, which depict a ring 4630 and sensor packages 4650a, 4650b according to another embodiment of the present disclosure. In one example, ring 4630 may be configured similar to ring 4030 in that it includes a body 4632, head 4634, and shaft 4636. However, sensor packages 4650a, 4650b include an alternative configuration having sensor-bearing surfaces 4652a, 4652b. In this example, sensor-bearing surfaces 4652a, 4652b have an angled planar configuration rather than the dome surface configuration of FIGS. 58A-58I or the conical surface configuration of FIG. 60. Unlike the dome surface which is curved in both a first plane parallel to the central axis and a second plane perpendicular to the central axis, and unlike the conical surfaces which are curved in the second plane but linear in the first plane, the angled planar sensor-bearing surfaces 4652a, 4652b are not curved in either the first plane or the second plane. Instead, the angled planar sensor-bearing surfaces 4652a, 4652b are flat surfaces that are angled relative to the central axis A. As shown in FIGS. 62A-62D, two separate sensor packages 4650a, 4650b may be provided, each having a planar sensor surface that is angled distally toward a catheter shaft 4610. Together, first and second planar sensor surfaces 4652a, 4652b may form a V-shape when viewed in front elevation. In the embodiment depicted, the planes of the first and second planar sensor surfaces 4652a, 4652b converge, but the surfaces themselves do not converge. However, in other examples, the surfaces themselves may converge.

[0350] Ring 4630 may include a head 4634, a body 4632 extending proximally from head 4634, and a shaft 4636 extending proximally from body 4632. A delivery catheter shaft 4610 may extend through ring 4630 and may be releasably coupled to a fixation device 4612. Fixation device 4612 may include a coupling member 4624, a first clamp 4614a having a first proximal element 4616a and a first distal element 4618a, and a second clamp 4614b having a second proximal element 4616b and a second distal element 4618b. Fixation device 4612 may be similar to fixation device 112 described above.

[0351] First sensor package 4650a may include first planar sensor surface 4652a, which may be a flat, angled sensor-bearing surface disposed at a first side of delivery catheter shaft 4610. First planar sensor surface 4652a may be angled such that it extends distally toward delivery catheter shaft 4610 and faces toward first clamp 4614a. Second sensor package 4650b may include second planar sensor surface 4652b, which may be a flat, angled sensor-bearing surface disposed at a second side of delivery catheter shaft 4610, opposite first planar sensorAtty Docket No. ABTEVA-0063PCT surface 4652a. Second planar sensor surface 4652b may be angled such that it extends distally toward delivery catheter shaft 4610 and faces toward second clamp 4614b.

[0352] As shown in FIG. 62B, a central axis A may extend axially along ring 4630 and delivery catheter shaft 4610. An angle a may be measured from central axis A to each of first planar sensor surface 4652a and second planar sensor surface 4652b. Angle a may be in a range of about 190 degrees to about 210 degrees from central axis A (or about 15 degrees to about 25 degrees from a horizontal plane perpendicular to central axis A, + / - 5 degrees). The angular relationship of first and second planar sensor surfaces 4652a, 4652b may be symmetrical about central axis A.

[0353] As shown in FIGS. 62A-62D, sensor packages 4650a, 4650b may be two separate structures, each having one of the planar sensor surfaces 4652a, 4652b. In other embodiments, a single, unitary sensor package may be provided having both first planar sensor surface 4652a and second planar sensor surface 4652b. In either configuration, the sensor package or packages may be coupled to ring 4630, such as to head 4634 thereof. In some embodiments, ring 4630 may include a cavity 4638 for receipt of the sensor package or packages, similar to the cavities described with respect to the foregoing embodiments. In other embodiments, sensor packages 4650a, 4650b may be coupled to an outer surface of head 4634.

[0354] Sensor packages 4650a, 4650b may collectively include two sensor arrays 4670a, 4670b. with one sensor array on each sensor package. First sensor array 4670a may be disposed on first planar sensor surface 4652a and may be directed toward first clamp 4614a. Second sensor array 4670b may be disposed on second planar sensor surface 4652b and may be directed toward second clamp 4614b. Each sensor array 4670a, 4670b may include one or more sensors 4672, such as piezoelectric sensors. In various examples, each sensor array 4670a, 4670b may include one to twenty-five sensors 4672. The sensors 4672 in each array may be arranged in a rectangular pattern with a long dimension extending perpendicular to a width of the corresponding clamp 4614a, 4614b. However, other array patterns are possible, such as circular patterns, shapes having irregular widths, or other configurations.

[0355] As shown in FIG. 62C, sensor packages 4650a, 4650b may include openings 4662 for control lines, such as proximal element lines 101a and lock line 102. One opening 4662 may extend through first sensor package 4650a for passage of a proximal element line that controls first proximal element 4616a. Another opening 4662 may extend through second sensor package 4650b for passage of a proximal element line that controls second proximalAtty Docket No. ABTEVA-0063PCT element 4616b. A central opening 4660 may be defined between first and second sensor packages 4650a, 4650b for passage of delivery catheter shaft 4610.

[0356] Sensor packages 4650a, 4650b may be coupled to ring 4630 such that first and second planar sensor surfaces 4652a, 4652b face distally toward fixation device 4612. Because ring 4630 rotates with delivery catheter shaft 4610, sensor arrays 4670a, 4670b may remain aligned with their respective clamps 4614a, 4614b during rotation of delivery catheter shaft 4610. The angled planar configuration may provide several benefits, including simplified manufacturing compared to curved or conical surfaces and reduced complexity and cost while still providing detection capability for tissue captured by each clamp 4614a, 4614b.

[0357] As mentioned above with respect to FIGS. 59B and 61C, the collective width of the sensor arrays may be greater than the width of the corresponding proximal elements. This width relationship is an optional, but beneficial feature of all of the sensor array and sensor package examples disclosed herein as it facilitates directing ultrasonic beams toward and beyond the side edges (e.g., side edges 4384 of FIG. 59B and side edges 4584 of FIG. 61C) of the proximal elements to define the width component of the detection zone, thereby enabling detection of tissue extending beyond the side edges. In this regard, a first width W1 may be defined as the width of the first and second proximal elements 4382a, 4382b, 4582a, or 4582b measured between side edges 4384 or 4584 thereof, and a second width W2 may be defined as the collective width of the sensor arrays (e.g., sensor arrays 4370a, 4370b, 4370c, 4370d, 4570a, 4570b, 4570c, or 4570d). Second width W2 may be greater than first width W1 such that the sensor arrays extend beyond the side edges 4384 or 4584 of the proximal elements 4382a, 4382b, 4582a, or 4582b. This may allow the sensor arrays to detect tissue that extends beyond the edges of the proximal elements, which may assist in assessing the adequacy of tissue capture, which may be during a TEER procedure, for example. Although the width relationship is explicitly illustrated in FIGS. 59B and 61C with respect to the second dome embodiment and second conical embodiment, the same width relationship may be implemented in the dome surface example of FIGS. 58A-58I, the conical surface example of FIG. 60, and the angled planar surface example of FIGS. 62A-62D.

[0358] The sensor arrays (e.g., sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a, or 4670b) of the sensor packages 4050, 4350, 4450, 4550, or 4650 described herein may include one or more piezoelectric sensors (e.g., sensors 4072, 4372, 4472, 4572, or 4672). In oneAtty Docket No. ABTEVA-0063PCT example, the piezoelectric sensors may be Piezoelectric Micromachined Ultrasonic Transducers (PMUTs), which are a type of Micro-Electro-Mechanical Systems (MEMS). PMUT sensors may be beneficial for transcatheter applications because they offer a miniaturized size and can be scalable.

[0359] In another example, the piezoelectric sensors 4072, 4372, 4472, 4572, or 4672 may be lead zirconate titanate (PZT) sensors. PZT sensors utilize bulk ceramic material and operate in a thickness mode in which the piezoelectric element expands and contracts. PZT sensors may operate in a frequency range from kHz to tens of MHz.

[0360] Each sensor array 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a, or 4670b may include one to twenty-five sensors 4072, 4372, 4472, 4572, or 4672. For a clip delivery system (CDS) having two clamps 4014a, 4014b, 4114a, 4114b, 4214a, 4214b, 4414a, 4414b, 4614a, or 4614b, a total of four to one hundred sensors may be utilized. The number of sensors may be selected based on the desired detection range, with a higher number of sensors providing a wider detection range. One or more of the sensors in each array may be arranged in a rectangular pattern, such as with the long extension of the rectangular array extending perpendicular to the width of the corresponding proximal element 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b. However, other array patterns are possible, such as circular patterns or other configurations. Additionally, the number of sensor arrays per sensor package may vary. For example, sensor packages 4050 and 4650 may include two sensor arrays, sensor packages 4350 and 4550 may include four sensor arrays, and sensor package 4450 may include six sensor arrays. The number of sensor arrays may be selected based on factors such as the desired detection coverage, the geometry of the sensor-bearing surface, and manufacturing considerations.

[0361] Rings 4030, 4330, 4430, 4530, or 4630 may be made from stainless steel, such as 304 stainless steel, 316L stainless steel, and / or 316LVM stainless steel. The sensor packages 4050, 4350, 4450, 4550, or 4650 may be made from various materials suitable for the sensor mount or carrier. For example, ceramics, engineering polymers, or flexible printed circuit boards (PCBs) may be used to construct the sensor substrate forming at least a portion of the sensor packages. The PMUT sensor arrays (e.g., sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a,Atty Docket No. ABTEVA-0063PCT or 4670b) may utilize a thin piezoelectric layer on a micromachined diaphragm, which may be placed over a silicon substrate.

[0362] Electrical wires from the sensors 4072, 4372, 4472, 4572, or 4672 may be routed through openings (e.g., openings 4062 in FIG. 58A-58I, openings 4362 in FIGS. 59A-59B, or corresponding openings in other embodiments) in the ring 4030, 4330, 4430, 4530, or 4630 so that such wires may be routed through a delivery catheter to a delivery catheter handle (e.g., handle 3751) and / or an external control system. As described above with respect to rings 4030, 4330, 4430, 4530, or 4630, such rings may include minor lumens (e.g., minor lumens 4044 as shown in FIG. 58C, or corresponding minor lumens in other embodiments) for sensor wires arranged at intervals about a major lumen for the catheter shaft 4010, 4310, 4410, 4510, or 4610. These holes may be adjusted in size or relocated to any location between 0 degrees and 90 degrees in one of four quadrants on the ring, allowing the wires to be fed directly through the holes. Holes at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock positions may be suitable arrangements for proximal element line and lock lines. In some examples, one to eight wires per quadrant may be routed for the arrayed sensors through the minor lumens 4046. The ring 4030, 4330, 4430, 4530, or 4630 may be connected to a delivery catheter shaft 4010, 4310, 4410, 4510, or 4610 (DC shaft) that has matching hole locations.

[0363] Referring now in addition to FIGS. 58A-62D and FIG. 21, the sensor packages 4050, 4350, 4450, 4550, and 4650 of the ring sensor embodiments described above may be integrated with piezoelectric sensing system 700. In this regard, each sensor array (e.g., sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a, and 4670b) may include one or more piezoelectric sensors 4072, 4372, 4472, 4572, or 4672, such as PMUTs or PZT sensors, which may be configured to emit ultrasonic waves toward respective proximal elements (e.g., first proximal elements 4016a, 4382a, 4416a, 4582a, or 4616a, and second proximal elements 4016b, 4382b, 4416b, 4582b, or 4616b) and receive reflected waves therefrom. The sensors within each array may be electrically coupled to signal processing unit 702 via leads extending through the minor lumens of the ring 4030, 4330, 4430, 4530, or 4630, and through a delivery catheter shaft (e.g., delivery catheter shaft 4010, 4310, 4410, 4510, or 4610) to a delivery device handle (e.g., delivery device handle 3751 of FIG. 54).

[0364] Signal processing unit 702 may be configured to receive signals from the sensor(s) 720 (e.g., signals from arrays of the sensor package 4050, 4350, 4450, 4550, or 4650Atty Docket No. ABTEVA-0063PCT and process the received signals to generate output signals indicative of conditions at the target site. In one example, signal processing unit 702 may be disposed within a delivery device handle (e.g., delivery device handle 3751). In another example, signal processing unit 702 may be positioned external to the delivery system and coupled thereto via a cable or wireless connection. The processed signals generated from signal processing module 706 may be transmitted to output device 710 for presentation to a surgeon, enabling real-time assessment of tissue capture during a TEER procedure. Power source 704 may provide electrical energy to the sensor arrays disclosed herein and signal processing module 706, and interface 708 may couple the sensor arrays to signal processing unit 702.

[0365] Referring now in addition to FIGS. 63-65, signal processing module 706 of signal processing unit 702 may be configured to process signals from the sensor arrays of the sensor package 4050, 4350, 4450, 4550, or 4650 and generate one or more types of output signals for presentation on output device 710. The output signals may include B-scan signals, M-scan signals, and tissue capture indicator signals, each of which provides different information to assist the surgeon in assessing tissue capture.

[0366] FIG. 63 illustrates an exemplary B-scan display output that may be generated by signal processing module 706 and presented on output device 710. B-scan, also referred to as brightness mode scanning, provides a two-dimensional cross-sectional image of the region being interrogated by the sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f. 4570a, 4570b. 4570c, 4570d, 4670a, or 4670b. B-scan may be generated using a transducer array (i.e., multiple sensors 4072, 4372, 4472, 4572, or 4672 arranged in an array pattern), wherein the reflected signals from each sensor may be combined to generate the B-scan image. The B-scan display may present a sector scan view having a fan-shaped or wedge-shaped field of view, with grayscale representation indicating the relative densities of structures within the field of view. Brighter regions may indicate denser structures such as the proximal elements 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b, the distal elements 4018a, 4018b, 4418a, 4418b, 4618a, or 4618b, and captured tissue, while darker regions may indicate fluid such as blood.

[0367] In operation, the B-scan display may be used to assess and confirm that enough leaflet is grasped within the gripper. When tissue is present between the proximal and distal elements of each clamp 4014a, 4014b, 4114a, 4114b, 4214a, 4214b, 4414a, 4414b, 4614a, or 4614b, the B-scan image may show increased brightness in the region between the clampAtty Docket No. ABTEVA-0063PCT elements corresponding to the increased density of the captured tissue. The B-scan display may also enable the surgeon to assess the depth of tissue insertion by observing how far the tissue extends toward the fixed ends of the proximal and distal elements. Additionally, the B-scan display may reveal the thickness and structure of the captured tissue, which may assist in determining whether the tissue capture is of sufficient quality for successful fixation.

[0368] FIG. 64 illustrates an exemplary M-scan display output that may be generated by signal processing module 706 and presented on output device 710. M-scan, also referred to as motion mode scanning, provides a one-dimensional representation of tissue movement over time. The M-scan display may be generated using a single sensor element or a sensor array (e.g., sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d. 4670a, or 4670b), with the reflected signals plotted against time to show motion of structures within the field of view. In the M-scan display, time may be represented along a horizontal axis and depth may be represented along a vertical axis, with bright lines indicating the positions of tissue interfaces at each point in time.

[0369] In operation, the M-scan display may be used to assess and confirm that enough leaflet is grasped within the gripper. When tissue is captured between the proximal and distal elements of the clamps 4014a, 4014b, 4114a, 41 14b, 4214a, 4214b, 4414a, 4414b, 4614a, or 4614b, the M-scan display may show characteristic wave-like motion patterns corresponding to the cyclical movement of the captured leaflet tissue through systolic and diastolic phases of the cardiac cycle. Multiple cardiac cycles may be observed on a single M-scan display, providing a continuous record of tissue motion. The presence of such repeating motion patterns may confirm that tissue has been captured, while the amplitude and frequency of the motion may provide information about the nature of the captured tissue. Conversely, the absence of tissue motion patterns or irregular patterns may indicate that tissue has not been captured or has slipped out of the clamp.

[0370] FIG. 65 illustrates an exemplary tissue capture indicator display that may be generated by signal processing module 706 and presented on output device 710. The tissue capture indicator may provide a simplified visual representation of tissue capture status, which may be easier to interpret than B-scan or M-scan displays during a procedure. As shown in FIG. 65, the tissue capture indicator may include a depth scale indicating the depth of field being interrogated by the sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a, or 4670b. The displayAtty Docket No. ABTEVA-0063PCT may show regions of varying attenuation, including a region of low attenuation corresponding to liquid (e.g., blood) appearing relatively dark, and a solid white block region of high attenuation corresponding to solid structures such as the proximal and distal elements of a fixation device and any tissue captured therebetween.

[0371] In operation, the tissue capture indicator may function as follows. When the sensor arrays emit ultrasonic waves toward the proximal elements 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b and receive reflected waves therefrom, the signal processing module 706 may analyze the reflected waves to generate a visual representation of tissue capture. As the density of the region between the clamp elements (i.e., proximal elements and distal elements) increases due to the presence of tissue between the distal elements 4018a, 4018b, 4418a, 4418b, 4618a, or 4618b and the proximal elements 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b, the solid white block increases in size.

[0372] The solid white block indicator may be particularly useful for confirming successful tissue capture. Beams from all sensors may be directed towards specific detection zones at and / or adjacent to the side edges of the proximal elements. If tissue is present in the detection zone, the length of the solid white block would increase. If there is no tissue present, then there would be no change in the length of the solid white block. This provides a clear, intuitive indication of whether tissue has been captured between the proximal and distal elements. As described with respect to FIGS. 20A and 20B, tissue insertion to at least 50% of the grip length Lgrip may be associated with sufficient pinch force for secure tissue capture and reduced risk of single leaflet device attachment (SLDA). The depth scale shown on the display may assist the surgeon in assessing whether tissue has been inserted to at least this threshold depth.

[0373] In some examples, the tissue capture indicator may include separate indicators for each clamp of the fixation device 4012, 4112, 4212, 4412, or 4612. For example, a first indicator may correspond to the first clamp 4014a, 4114a, 4214a, 4414a, or 4614a and may reflect signals from sensor arrays directed toward the first proximal element 4016a, 4382a, 4416a, 4582a, or 4616a, while a second indicator may correspond to the second clamp 4014b, 4114b, 4214b, 4414b, or 4614b and may reflect signals from sensor arrays directed toward the second proximal element 4016b, 4382b, 4416b, 4582b, or 4616b. This configuration enables the surgeon to independently assess tissue capture in each clamp and identify situations where only one leaflet has been captured (i.e., SLDA).Atty Docket No. ABTEVA-0063PCT

[0374] Referring now in addition to FIG. 57, the sensor packages 4050, 4350, 4450, 4550, or 4650 of FIGS. 58A-62D may be used in accordance with method 3800. In the delivering step 3802, a fixation device 4012, 4112, 4212, 4412, or 4612 having a ring 4030, 4330, 4430, 4530, or 4630 with a sensor package 4050, 4350, 4450, 4550, or 4650 disposed therein may be delivered to a target location within a patient, such as within a mitral valve or a tricuspid valve.

[0375] In the directing step 3804, a first tissue (e.g., a first valve leaflet) may be directed into a space between a first proximal element 4016a, 4382a, 4416a, 4582a, or 4616a and a first distal element 4018a, 4418a, or 4618a of a first clamp 4014a, 4114a, 4214a, 4414a, or 4614a of the fixation device, and a second tissue (e.g., a second valve leaflet) may be directed into a space between a second proximal element 4016b, 4382b, 4416b, 4582b, or 4616b and a second distal element 4018b, 4418b, or 4618b of a second clamp 4014b, 4114b, 4214b, 4414b, or 4614b of the fixation device. During this step, the sensor arrays (e.g., sensor arrays 4070a, 4070b, 4370a, 4370b, 4370c, 4370d, 4470a, 4470b, 4470c, 4470d, 4470e, 4470f, 4570a, 4570b, 4570c, 4570d, 4670a, or 4670b) of the sensor package may emit ultrasonic waves toward the respective proximal elements when the distal elements are in an open position. The ultrasonic waves may be directed at angles corresponding to the sensor-bearing surfaces of the sensor package, such as the dome surface 4058 or 4358, the first and second conical surfaces 4452, 4454, 4558, or 4560, or the planar sensor surfaces 4652a or 4652b.

[0376] In the closing step 3806, the first and second clamps 4014a, 4014b, 4114a, 41 14b, 4214a, 4214b, 4414a, 4414b, 4614a, or 4614b may be closed by moving the first and second proximal elements 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b toward the respective first and second distal elements 4018a, 4018b, 4418a, 4418b, 4618a, or 4618b. As the clamps close, any tissue disposed between the proximal and distal elements may be compressed, which may increase the density of material in the detection zone observable by the sensor arrays.

[0377] In the measuring step 3808, a response may be measured from the sensor arrays of the sensor package 4050, 4350, 4450, 4550, or 4650. The sensor arrays may emit ultrasonic waves toward the clamps and receive reflected waves therefrom. The reflected waves may be converted to electrical signals by sensors 4072, 4372, 4472, 4572, or 4672 and processed by signal processing module 706 to generate output signals, which may include B-scan signals (FIG. 63), M-scan signals (FIG. 64), and / or tissue capture indicator signals (FIG. 65).Atty Docket No. ABTEVA-0063PCT

[0378] In the determining step 3810, the presence or absence of tissue within the respective first and second clamps 4014a, 4014b, 4114a, 4114b, 4214a, 4214b, 4414a, 4414b, 4614a, or 4614b may be determined based on the measured response from the sensor arrays. In one example, the B-scan display (FIG. 63) may be observed to assess and confirm that enough leaflet is grasped within the gripper. In another example, the M-scan display (FIG. 64) may be observed to assess and confirm that enough leaflet is grasped within the gripper based on characteristic motion patterns. In a further example, the tissue capture indicator (FIG. 65) may be observed, wherein if tissue is present within the detection zone at and / or adjacent to the side edges of the proximal elements, the length of the solid white block would increase. Conversely, if there is no tissue present, then there would be no change to the solid white block.

[0379] The sensor package configuration of the ring 4030, 4330, 4430, 4530, or 4630 may provide advantages for tissue detection during a TEER procedure. Because the sensor arrays are disposed on the sensor package 4050, 4350, 4450, 4550, or 4650 within the ring at a location distal to the proximal elements 4016a, 4016b, 4382a, 4382b, 4416a, 4416b, 4582a, 4582b, 4616a, or 4616b, the sensor arrays may have a direct line of sight to the tissue capture region when the clamps are in the open position. Additionally, because the ring rotates with the delivery catheter shaft 4010, 4310, 4410, 4510, or 4610, the sensor arrays may remain aligned with the respective proximal elements throughout the procedure, ensuring consistent detection regardless of device orientation. Furthermore, the sensor-bearing surfaces of the sensor package (e.g., dome surface 4058 or 4358, first conical surface 4452 or 4558, second conical surface 4454 or 4560, or planar sensor surfaces 4652a or 4652b) may be angled to direct ultrasonic beams toward specific zones of the proximal elements to help assess and confirm that enough leaflet is grasped within the gripper.

[0380] Although the subject matter disclosed herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications set forth in this disclosure. It is therefore to be understood that numerous modifications may be made to the exemplary embodiments and that other arrangements may be devised, such as combining one or more features of one embodiment with another embodiment or features from a plurality of embodiments, as an example. Thus, the exemplary embodiments herein are not intended to be exhaustive or to limit the disclosed subject matter to such embodiments.

Claims

Atty Docket No. ABTEVA-0063PCTCLAIMS1. A system for securing tissue comprising: a fixation device comprising: a center portion, and a first clamp extending outwardly from the center portion and having: a first distal element being moveable between an open and a closed position and having a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end, and and a first proximal element being moveably disposed opposite the first distal element and having a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end of the first proximal element; and a piezoelectric sensing system comprising: a first piezoelectric sensor coupled to one of the first distal element, the first proximal element, and the center portion, a signal processing unit having a power source and a signal processing module, the signal processing module being configured to receive signals from the first piezoelectric sensor corresponding to a parameter associated with pressure, process the received signals, and generate an output signal indicative of the parameter, and an interface configured to couple the first piezoelectric sensor to the signal processing unit for transmitting the signals from the first piezoelectric sensor to the signal processing unit.

2. The system of claim 1, wherein the first piezoelectric sensor is coupled to one of the first proximal element and first distal element and is positioned between the midline and the fixed end thereof.

3. The system of claim 1, wherein the first piezoelectric sensor is coupled to one of the first proximal element and the first distal element and positioned at the midline thereof.

4. The system as in any of the preceding claims, wherein the piezoelectric sensing system further includes a second piezoelectric sensor.

5. The system of claim 4, wherein the second piezoelectric sensor is coupled to at least one of the first proximal element and first distal element and is positioned between the free end and the midline thereof.Atty Docket No. ABTEVA-0063PCT6. The system of claim 4, wherein the second piezoelectric sensor is coupled to one of the first proximal element and the first distal element and is positioned at the midline thereof.

7. The system as in any one of the preceding claims, wherein the first proximal element includes a plurality of frictional elements extending therefrom, and the first piezoelectric sensor is coupled to one of the frictional elements.

8. The system as in any one of the preceding claims, wherein the first proximal element includes a first side portion, a second side portion, and a window disposed between the first and second side portions, and the first piezoelectric element is disposed on the first side portion.

9. The system as in any one of the preceding claims, wherein the first distal element includes an elongate body and first and second wing portions extending laterally outwardly from the elongate body, and the first piezoelectric element is disposed on the first wing portion.

10. The system as in claims 5 or 6, wherein the piezoelectric sensing system includes a sensor array, and the first and second piezoelectric sensors are included in the sensor array.

11. The system of claim 7, wherein: the first and second piezoelectric sensor each include a piezoelectric element and first and second electrodes positioned at opposite sides of the piezoelectric element, and the sensor array includes an encapsulation enclosing both the first and second piezoelectric sensors.

12. The system of claim 10, wherein the piezoelectric element of each of the first and second piezoelectric sensors is made from one of quartz, lead zirconate titanate (PZT), barium titanate, and polyvinylidene fluoride (PVDF).

13. The system of claim 10, wherein the sensor array includes a first lead, a second lead, and a third lead, the first lead is coupled to the first electrode of each of the first and second piezoelectric sensors, the second lead is coupled to the second electrode of the first piezoelectric sensor, and the third lead is coupled to the second electrode of the second piezoelectric sensor.Atty Docket No. ABTEVA-0063PCT14. The system of claim 1, wherein the first piezoelectric sensor is a strip sensor having a width and a length, the length of the first piezoelectric sensor being at least twice the width.

15. The system of claim 14, wherein the first piezoelectric sensor is coupled to one of the first proximal element and first distal element and extends along a length extending from the midline to 75% of the length as measured from the free end thereof.

16. The system of claim 14, wherein the first piezoelectric sensor is coupled to one of the first proximal element and first distal element and extends along a length extending from the midline to the fixed end thereof.

17. The system as in claims 15 or 16, wherein the piezoelectric sensing system further includes a second piezoelectric sensor, the second piezoelectric sensor being a strip sensor having a width and a length, the length of the second piezoelectric sensor being at least twice the width.

18. The system of claim 17, wherein the second piezoelectric sensor is coupled to one of the first proximal element and first distal element and extends along a length extending from the midline to 25% of the length as measured from the free end thereof.

19. The system of claim 17, wherein the second piezoelectric sensor is coupled to one of the first proximal element and first distal element and extends along a length extending from the free end to the midline thereof.

20. The system as in any of claims 14-19, wherein the first piezoelectric sensor has a piezoelectric element is made from PVDF.

21. The system of claim 4, wherein the second piezoelectric sensor is coupled to the first proximal element and the first distal element and is positioned at the midline thereof.

22. The system of claim 1, wherein the center portion includes a coupling member configured to be releasably coupled to a delivery catheter, and the first piezoelectric sensor is coupled to the coupling member.

23. The system of claim 1, wherein the center portion includes a compressible coaptation body extending radially outwardly relative to a longitudinal axis of the fixation device and being compressible radially inwardly, and the first piezoelectric sensor is coupled to the coaptation body.

24. The system as in claims 22 or 23, further comprising a second piezoelectric sensor coupled to the center portion.Atty Docket No. ABTEVA-0063PCT25. The system of claim 24, wherein a first plane bisects the center portion, a second plane is oriented perpendicular to the first plane and intersects the first clamp, and the first and second piezoelectric sensors are disposed at opposite sides of the center portion between the first and second planes.

26. The system as in claims 22 or 23, wherein the first piezoelectric sensor is a strip sensor having a length and a width, the length of the first piezoelectric sensor being at least twice the width, and the first piezoelectric sensor extends about at least a portion of a perimeter of the center portion.

27. The system of claim 1, further comprising a delivery system, the delivery system including a delivery handle and a delivery catheter extending from the delivery handle.

28. The system of claim 27, wherein the signal processing unit is disposed within the delivery handle.

29. The system of claim 28, wherein the interface is a hardwired interface extending from the first piezoelectric sensor, through the delivery catheter, and to the signal processing unit within the handle.

30. The system of claim 29, wherein the delivery catheter includes a shaft having a plurality of spring arms each having first electrical terminal and an actuator rod extendable through the shaft, and the center portion of the fixation device includes a coupling member having second electrical terminals corresponding with the first electrical terminals, wherein moving the actuator rod in a first direction urges the spring arms into engagement with the coupling member and the first electrical terminals into engagement with the second electrical terminals, and moving the actuator rod in a second direction disengages the spring arms from the coupling member and the first electrical terminals from the second electrical terminals.

31. The system of claim 28, wherein the delivery system includes a first proximal element line extending from the delivery catheter and is releasably coupled to the first proximal element, the first proximal element line comprised of insulated wiring and being configured to electrically couple the first piezoelectric sensor to the signal processing unit.

32. The system as in any of claims 27-31, wherein the delivery handle includes an LED array having an LED associated with the first piezoelectric sensor.Atty Docket No. ABTEVA-0063PCT33. The system as in any of the preceding claims, further comprising a second distal element extending from the center portion, and a second proximal element disposed opposite the second distal element.

34. A system for securing tissue comprising: a delivery system comprising: a delivery handle, and a delivery catheter extending from the delivery handle; a fixation device releasably coupled to the delivery catheter and comprising: a center portion, and a first clamp extending outwardly from the center portion and having: a first distal element being moveable between an open and a closed position and having a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end, and a first proximal element being moveably disposed opposite the first distal element and having a fixed end, a free end, a length extending therebetween, and a midline equidistant between the free end and the fixed end of the first proximal element; and a first piezoelectric ultrasonic transducer coupled to the delivery catheter, the first piezoelectric ultrasonic transducer being configured to emit ultrasonic waves toward the first clamp when the first distal element is in the open position and receive reflected waves from the first clamp when in the open position.

35. The system of claim 34, wherein the first piezoelectric ultrasonic transducer has a first position in which the first piezoelectric ultrasonic transducer is nested within the delivery catheter, and a second position in which the first ultrasonic transducer is extended from the delivery catheter in a direction toward the first clamp when the first distal element is in the open position.

36. The system as in claim 34 or 35, wherein the fixation device includes a second clamp having a second distal element and a second proximal element.

37. The system of claim 36, further comprising a second piezoelectric ultrasonic transducer coupled to the delivery catheter, the second piezoelectric ultrasonic transducer being configured to emit ultrasonic waves toward the second clamp when the second distal elementAtty Docket No. ABTEVA-0063PCT is in the open position and receive reflected waves from the second clamp when the second distal element is in the open position.

38. The system of claim 37, wherein the second piezoelectric ultrasonic transducer has a first position in which the second piezoelectric ultrasonic transducer is nested within the delivery catheter, and a second position in which the second ultrasonic transducer is extended from the delivery catheter in a direction toward the second clamp when the second distal element is in the open position.

39. The system as in any of claims 34-38, further comprising a signal processing unit having a power source and a signal processing module, the signal processing module being configured to receive signals from the first piezoelectric sensor corresponding to the reflected waves, process the received signals, and generate an output signal indicative of reflected waves.

40. The system of claim 39, wherein the output signal is an M-mode signal.41 . The system of claim 34, further comprising a first piezoelectric pressure sensor coupled to one of the first distal element, the first proximal element, and the center portion.

42. The system of claim 41, wherein the first piezoelectric sensor is coupled to one of the first proximal element and first distal element and is positioned between the midline and the fixed end thereof.

43. The system of claim 41, wherein the first piezoelectric sensor is coupled to one of the first proximal element and the first distal element and positioned at the midline thereof.

44. The system as in any of claims 41-43, wherein the piezoelectric sensing system further includes a second piezoelectric sensor.

45. The system of claim 44, wherein the second piezoelectric sensor is coupled to at least one of the first proximal element and first distal element and is positioned between the free end and the midline thereof.

46. fhe system of claim 44, wherein the second piezoelectric sensor is coupled to one of the first proximal element and the first distal element and is positioned at the midline thereof.

47. The system as in any of claims 41-46, wherein the first proximal element includes a plurality of frictional elements extending therefrom, and the first piezoelectric sensor is coupled to one of the frictional elements.Atty Docket No. ABTEVA-0063PCT48. The system as in any of claims 41-47, wherein the first proximal element includes a first side portion, a second side portion, and a window disposed between the first and second side portions, and the first piezoelectric element is disposed on the first side portion.

49. The system as in any of claims 41 -48, wherein the first distal element includes an elongate body and first and second wing portions extending laterally outwardly from the elongate body, and the first piezoelectric element is disposed on the first wing portion.

50. A system for securing tissue comprising: a delivery catheter having a shaft; a fixation device releasably coupled to the shaft and comprising: a center portion, a first clamp extending outwardly from the center portion and having a first distal element and a first proximal element, and a second clamp extending outwardly from the center portion and having a second distal element and a second proximal element; and a sensor package disposed at a distal end of the shaft and comprising: a sensor-bearing surface, and a first sensor array disposed on the sensor-bearing surface and directed toward the first clamp, the first sensor array including one or more piezoelectric sensors configured to emit ultrasonic waves toward the first proximal element and receive reflected waves therefrom.

51. The system of claim 50, further comprising a ring coupled to the delivery catheter, and the shaft extending through the ring.

52. The system of claim 51, wherein the ring comprises a head having a cavity, and the sensor package is disposed within the cavity such that the sensor-bearing surface is exposed at a distal side of the ring.

53. The system of claim 51 or 52, wherein the ring comprises a major lumen for passage of the shaft and a plurality of minor lumens arranged about the major lumen for passage of at least one sensor wire and at least one proximal element line for actuating the first proximal element.

54. The system of any one of claims 51-53, wherein the ring is coupled to the delivery catheter such that the ring rotates with the delivery catheter, and the first sensor array maintains rotational alignment with the first proximal element.Atty Docket No. ABTEVA-0063PCT55. The system of any one of claims 50-54, wherein the sensor package further comprises a second sensor array disposed on the sensor-bearing surface and directed toward the second clamp.

56. The system of any one of claims 50-55, wherein the sensor-bearing surface comprises a dome surface.

57. The system of any one of claims 50-55, wherein the sensor-bearing surface comprises a first conical surface and a second conical surface extending circumferentially about a central axis of the sensor package, the first conical surface being disposed at a first angle relative to the central axis, and the second conical surface being disposed at a second angle relative to the central axis, the first angle being greater than the second angle.

58. The system of any one of claims 50-55, wherein the sensor-bearing surface comprises a first planar surface angled toward the first clamp, and the sensor package further comprises a second planar surface angled toward the second clamp.

59. The system of claim 58, wherein the first and second planar surfaces form a V- shape.

60. The system of any one of claims 50-59, wherein the first proximal element has a first width defined between side edges thereof, and the first sensor array has a second width greater than the first width such that the first sensor array extends beyond the side edges of the first proximal element.

61. The system of any one of claims 50-60, wherein the one or more piezoelectric sensors comprise piezoelectric micromachined ultrasonic transducers.

62. The system of any one of claims 50-61, further comprising a signal processing unit configured to receive signals from the first sensor array and generate an output signal, the output signal being one of a B-scan signal, an M-scan signal, and a tissue capture indicator signal.

63. Claim 63. The system of any one of claims 50-62, wherein the first sensor array is configured to direct ultrasonic beams toward a detection zone, the detection zone being a region where the first sensor array is configured to observe tissue.

64. Claim 64. The system of claim 63, wherein the detection zone has a width component and a length component defined by a direction in which the ultrasonic beams are emitted from the first sensor array.Atty Docket No. ABTEVA-0063PCT65. Claim 65. The system of claim 64, wherein the width component and the length component are a function of dimensions of the first sensor array and angles at which the one or more piezoelectric sensors are oriented.

66. Claim 66. The system of claim 65, wherein the angles at which the one or more piezoelectric sensors are oriented are a function of a geometry of the sensor-bearing surface.

67. Claim 67. The system of any one of claims 64-66, wherein the first proximal element has side edges and is formed from a solid metal structure, and the detection zone is focused at and / or adjacent to the side edges of the first proximal element.

68. Claim 68. The system of claim 67, wherein the width component is defined as an extent to which the detection zone extends transversely beyond the side edges of the first proximal element.

69. Claim 69. The system of claim 68, wherein the first proximal element has a width defined between the side edges, and a collective width component of the detection zone extends beyond both side edges of the first proximal element by a total distance corresponding to about 25% to about 75% of the width of the first proximal element.

70. Claim 70. The system of any one of claims 64-69, wherein the first proximal element has a length defined between a fixed end and a free end thereof, and the length component of the detection zone is defined relative to the length of the first proximal element.

71. Claim 71. The system of claim 70, wherein the length component extends along an entire length of the first proximal element.

72. Claim 72. The system of claim 70, wherein the length component extends along less than the entire length of the first proximal element.

73. Claim 73. The system of claim 72, wherein the length component overlaps with about 50% of the length of the first proximal element as measured from the free end thereof.

74. Claim 74. The system of claim 72, wherein the length component overlaps with about 25% to about 75% of the length of the first proximal element as measured from the free end thereof.

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