Delivery system for vfa cardiac therapy

Abstract

An implantable medical device delivery system includes a delivery catheter including an elongated body having a first portion defining a first lumen and a second portion defining a second lumen. An angle is defined between first and second axes defined by the first and second portions, respectively. The second axis is directed toward a left ventricular (LV) apex of a heart of a patient when the first axis is directed toward a CS. The first portion or elongated element can extend into the CS to anchor the delivery catheter relative to an orientation of the CS.

Description

[0001] The present disclosure relates to implantable medical devices, systems, and methods. In particular, the present disclosure relates to implantable medical devices, systems, and methods for delivery of cardiac therapy including single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia-related therapy.

[0002] The heart conduction system includes the sinoatrial (SA) node, the atrioventricular (AV) node, the bundle of His, the bundle branches, and the Purkinje fibers. A heartbeat is initiated in the SA node, which can be described as the heart's natural "pacemaker." The electrical impulse from the SA node causes the atrial myocardium to contract. The signal is conducted through the AV node, which inherently delays conduction to allow the atria to stop contracting before the ventricles begin to contract, providing proper AV synchrony. The electrical impulse is conducted from the AV node to the ventricular myocardium through the bundle of His, the bundle branches, and the Purkinje fibers.

[0003] Patients with conduction system abnormalities, such as AV node conduction abnormalities or SA node dysfunction, can receive implantable medical devices (IMDs), such as pacemakers, for restoring more normal cardiac rhythm and AV synchrony. Some types of IMDs, such as cardiac pacemakers, implantable cardioverter-defibrillators (ICDs), or cardiac resynchronization therapy (CRT) devices, provide therapeutic electrical stimulation to the heart of a patient through one or more implanted endocardial, epicardial, or coronary vein electrodes positioned in or adjacent to the heart. Therapeutic electrical stimulation can be delivered to the heart in the form of pulses or shocks for pacing, cardioversion, or defibrillation. In some cases, the IMD can sense intrinsic depolarizations of the heart and control delivery of therapeutic stimulation to the heart based on the sensing.

[0004] Delivery of therapeutic electrical stimulation to the heart can be used to address a cardiac condition, such as ventricular dyssynchrony, which can occur in a patient. Ventricular dyssynchrony can be described as a lack of synchrony or a difference in the timing of contractions between the ventricles of the heart. Significant differences in the timing of contractions can reduce cardiac efficiency. CRT delivered by an IMD to the heart can enhance cardiac output by resynchronizing the electromechanical activity of the ventricles of the heart. Because CRT can deliver pacing to the right atrium, right ventricle, and left ventricle, CRT is sometimes referred to as "triple-chamber pacing."

[0005] In addition to cardiac pacing, cardiac arrhythmias can be treated by delivering shock therapy from, for example, an ICD for cardioversion or defibrillation, which can sense the patient's cardiac rhythm and classify the rhythm according to a tachyarrhythmia detection scheme in order to detect tachycardia or fibrillation episodes. Detected tachyarrhythmias can include ventricular tachycardia (VT), fast ventricular tachycardia (FVT), ventricular fibrillation (VF), atrial tachycardia (AT), and atrial fibrillation (AT). Anti-tachycardia pacing (ATP) (painless therapy) can be used to treat ventricular tachycardia (VT) to substantially terminate many monomorphic rapid rhythms. Although ATP is painless, ATP can not deliver effective therapy to all types of VT. For example, ATP can be less effective for polymorphic VT with variable morphology. Polymorphic VT and ventricular fibrillation (VF) can be more deadly and can require prompt treatment by electrical shock.

[0006] Dual chamber medical devices are available that include a transvenous atrial lead-carried electrode that can be placed in the right atrium and a transvenous ventricular lead-carried electrode that can be placed in the right ventricle through the right atrium. Such dual chamber medical devices are typically implanted in a subcutaneous pocket and the transvenous leads tunnel to the subcutaneous pocket. Further, such dual chamber medical devices can sense atrial and ventricular electrical signals and can provide both atrial and ventricular pacing as needed to promote normal cardiac rhythm and AV synchrony. Some dual chamber medical devices can treat both atrial and ventricular arrhythmias.

[0007] In some patients, a single chamber device can adequately meet the patient's needs. However, a single chamber device that is only capable of single chamber sensing and therapy can not fully address the cardiac conduction disease or abnormality of all patients, for example, patients with some form of AV dyssynchrony or tachycardia. Dual chamber sensing and / or pacing functionality can be used to restore more normal cardiac rhythm in addition to ICD functionality in some cases. SUMMARY

[0008] The technology of this disclosure generally relates to a delivery catheter that guides an implantable medical device or lead to the correct location in the triangle of Koch region and in an orientation to deliver pacing to the LV using CS as a physical reference.

[0009] In one aspect, the present disclosure provides an implantable medical device delivery system including an elongated element anchorable in a coronary sinus (CS) of a patient's heart. The system also includes a delivery catheter having an elongated body with a first portion defining a first lumen and a second portion defining a second lumen. The first lumen, located in a first distal region of the first portion, extends along a first axis, and the second lumen, located in a second distal region of the second portion, extends along a second axis that forms an angle with the first axis. The second axis is directed toward a left ventricular (LV) apex of the patient's heart when the anchorable elongated element is advanced through the first lumen into the CS.

[0010] In another aspect, the present disclosure provides a delivery catheter including a first portion advanceable into a coronary sinus (CS) of a patient's heart, the first portion having an elongated body defining a first lumen and an external passageway. A region of the first portion, adjacent to a CS ostium of the patient's heart, extends along a first axis when the first portion is advanced into the CS. The device includes a second portion having an elongated body defining a second lumen and having a laterally extending protrusion configured to be received in the external passageway of the first portion so as to slidably guide the second portion along a length of the first portion. A distal region of the second portion extends along a second axis that forms a fixed angle with the first axis when the protrusion is engaged in the passageway, such that the second axis is directed toward a left ventricular (LV) apex of the patient's heart when the first portion is advanced into the CS.

[0011] In yet another aspect, the present disclosure provides a method of delivering an implantable medical device, the method including advancing a first distal region of a first portion of a dual-lumen catheter toward a coronary sinus (CS) of a patient's heart. The first portion defines a first lumen, and the first distal region extends along a first axis. The method includes orienting a second distal region of a second portion of the dual-lumen catheter toward a Koch triangle region of the patient's heart. The second portion defines a second lumen, and the second distal region extends along a second axis that forms an angle with the first axis, such that the second axis is directed toward a left ventricular (LV) apex of the patient's heart when the first distal region is fully advanced toward the CS.

[0012] The details of one or more aspects of the present disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the technologies described in this disclosure will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1is a conceptual drawing of a patient's heart with a drawing in a standard 17-segment view of the left ventricle showing various electrode implantation locations for use with an exemplary system such as

[0014] Figure 2 is an example of an intracardiac medical device that can be delivered with a delivery system of Figure 1 is a conceptual drawing of an example of an intracardiac medical device that can be delivered with a delivery system of

[0015] Figure 3 is a perspective view of another example of an intracardiac medical device that can be delivered with a delivery system of Figure 1

[0016] Figure 4 is a conceptual drawing of a patient's heart with a drawing in a standard 17-segment view of the left ventricle showing various electrode implantation locations for use with an exemplary system such as Figures 1-3

[0017] Figure 5A is a conceptual drawing of one example of a delivery system of Figure 1

[0018] Figure 6 is a conceptual drawing of another example of a delivery system of Figure 1

[0019] Figure 7 is a flowchart of one example of a method of using a delivery system of Figure 1

[0020] Figure 8 is a flowchart of one example of a method of performing or implementing Figure 7

[0021] Figure 9 is a flowchart of another example of a method of performing or implementing Figure 7

[0022] Figure 10 is a flowchart of yet another example of a method of performing or implementing Figure 7 DETAILED DESCRIPTION

[0023] ​​​​​​​​The present disclosure relates to the delivery of implantable medical devices, systems, and methods for atrial to ventricular (VfA) cardiac therapy, including single or multi-chamber pacing (e.g., dual or triple chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia related therapy. Although reference is made herein to implantable medical devices (IMDs) such as pacemakers or ICDs, the methods and processes can be used with any medical device, system, or method related to a patient's heart. Various other applications will become apparent to those of ordinary skill in the art having the benefit of this disclosure.

[0024] The procedure for positioning a VfA device or lead in or at the correct implant location and orientation to target the correct direction to stimulate LV endocardial tissue can be difficult. At least two factors are considered for such VfA device placement. First, the catheter tip of the delivery catheter will be directed to the Koch triangle, which is a slippery location between the CS ostium and the tricuspid annulus, where it can be difficult to maintain placement of the catheter due to instability of the site. Second, once the catheter is in place, the device must be oriented in the correct tissue plane to position the electrodes in the LV tissue for pacing.

[0025] The present disclosure provides a delivery catheter that can be described as a dual or two-lumen catheter that can create stability at the target implant region and also provide the correct angle into tissue for providing VfA cardiac therapy. Specifically, an example of a delivery catheter can direct an implantable medical device or lead to the correct location in the Koch triangle region and in an orientation to deliver pacing to the LV using the CS as a physical reference. For example, an elongated element of the delivery catheter or extending through a portion of the delivery catheter into the CS can anchor the delivery catheter based on the orientation of the CS. In one embodiment, one lumen of the delivery catheter can be used to track or guide an elongated member into the CS, and another lumen of the delivery catheter can have a bend near the distal region to angle the device delivered therethrough into tissue in the correct orientation. The lumens can be described as positioned side-by-side.

[0026] Reference will now be made to the drawings, which depict one or more aspects described in this disclosure. It should be understood that other aspects not depicted in the drawings fall within the scope of this disclosure. The same reference numbers in different drawings identify the same components, steps, and the like. It should be understood, however, that the use of the same reference numbers in different drawings is not intended to be limiting. Rather, use of the same reference numbers in different drawings is intended to indicate that the referenced elements can be similar or identical.

[0027] While the present disclosure describes leadless and leaded implantable medical devices, reference is first made to Figure 1 which shows a conceptual diagram of a cardiac therapy system 2 including a leaded medical device 104, which can also be described as an implantable medical lead, that can be configured for single or dual chamber therapy and implanted in a patient’s heart 8. In some embodiments, the device 104 can be configured for single chamber pacing and can switch, for example, between single and multi-chamber pacing (e.g., dual or triple chamber pacing).

[0028] The device 104 is shown implanted in a target implant region 4 in the right atrium (RA) of the patient’s heart 8. The device 104 can include one or more fixation members (like the fixation members 20 in Figure 2 that anchor a distal end of the device to the atrial endocardium in the target implant region 4. The target implant region 4 can be located between the bundle of His 5 and the coronary sinus 3 and can be adjacent to the tricuspid valve 6. The device 104 can be described as a ventricular from atrial (VfA) device that can sense or provide therapy to one or both ventricles (e.g., the right ventricle, the left ventricle, or both ventricles, as the case can be) while typically disposed in the right atrium. In particular, the device 104 can include tissue-piercing electrodes that can be implanted from a region of the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the high basal region and / or septal region of the left ventricular myocardium of the patient’s heart.

[0029] Delivering the device 104 to the precise location in the target implant region 4 in the desired orientation can be challenging. The delivery catheter 100 can provide stable anchoring to the CS to facilitate delivery of the device 104 to the target implant region 4. Stable anchoring can be facilitated by use of the elongated element 102 extending through the delivery catheter 100. In some embodiments, the delivery catheter 100 can be described as a dual lumen catheter. The dual lumen catheter can include a first portion 101 defining a first lumen and a second portion 103 defining a second lumen, which can be integrally formed from a single piece of material or separately formed. The first portion 101 can extend into the CS, or the first lumen of the first portion can be used to deliver the elongated element 102 into the CS for anchoring. The second lumen can be used to deliver the implantable medical device 104 or a lead to the Koch triangle for implantation. The dual lumen catheter can be described as pre-shaped or configured to provide a fixed or deflectable angle between the first lumen and the second lumen, for example, at least at a distal region thereof. When the first lumen is aligned with the orientation of the coronary sinus using the elongated element 102 extending into the CS, the second lumen can be oriented at an angle and aimed at the Koch triangle region that implants the tissue-piercing electrodes of the device 104 from the Koch triangle region of the RA through the RA endocardium and central fibrous body into the high basal region and / or septal region of the LV myocardium. The delivery catheter 100 can be withdrawn after delivery of the device 104.

[0030] The device 104 can include one or more dart electrodes 12 having a straight axis extending from a distal region of the device 104 through the atrial myocardium and central fibrous body and into the ventricular myocardium 14 or along the ventricular septum without fully penetrating the ventricular endocardial or epicardial surface. In other words, the one or more dart electrodes 12 can not pierce the ventricular wall into the blood volume. The one or more dart electrodes 12 can each carry one or more electrode elements at a distal region of the shaft for positioning the one or more electrode elements within the ventricular myocardium for sensing ventricular signals and delivering ventricular pulses (e.g., depolarizing the left ventricle to cause contraction of the left ventricle). In some examples, the electrode elements at the distal region of the shaft can include a cathode electrode provided for use in a bipolar electrode pair for pacing and sensing. Although Figure 1 The implant region 4 is shown in FIG. 1 to enable positioning of one or more electrodes of the one or more dart electrodes 12 in the ventricular myocardium, it should be appreciated that devices having aspects disclosed herein can be implanted at other locations for multi-chamber pacing (e.g., dual or triple chamber pacing), single chamber pacing with multi-chamber sensing, single chamber pacing and / or sensing, or other clinical therapies and applications, as appropriate.

[0031] The cardiac therapy system 2 can also include a separate medical device 50 (in Figure 1The separate medical device can be positioned external to the patient's heart 8 (e.g., subcutaneously) and can be operably coupled to the patient's heart 8 to deliver cardiac therapy thereto. In one example, the separate medical device 50 can be an extravascular ICD. In some embodiments, the extravascular ICD can include a defibrillation lead with defibrillation electrodes. A therapy vector can exist between the defibrillation electrodes on the defibrillation lead and a housing electrode of the ICD. Further, one or more electrodes of the ICD can also be used to sense electrical signals related to the patient's heart 8. The ICD can be configured to deliver shock therapy including one or more defibrillation or cardioversion shocks. For example, if an arrhythmia is sensed, the ICD can send a pulse through the electrical lead to shock the heart and restore its normal rhythm. In some examples, the ICD can deliver shock therapy without the need to place electrical leads within the heart or to attach electrical wires directly to the heart (subcutaneous ICD). An example of an extravascular, subcutaneous ICD that can be used with the system 2 described herein can be described in U.S. Patent No. 9,278,229 (Reinke et al.) issued March 8, 2016.

[0032] The device 104 and the separate medical device 50 can cooperate to provide cardiac therapy to the patient's heart 8. For example, the device 104 and the separate medical device 50 can be used to detect tachycardia, monitor tachycardia, and / or provide tachycardia-related therapy. For example, the device 104 can wirelessly communicate with the separate medical device 50 to trigger shock therapy using the separate medical device 50. As used herein, "wireless" refers to operative coupling or connection without the use of metallic conductors connecting the device 104 and the separate medical device 50. In one example, wireless communication can use a unique, signaling, or triggering electrical pulse provided by the device 104 that conducts through the patient's tissue and is detectable by the separate medical device 50. In another example, wireless communication can use a communication interface (e.g., an antenna) of the device 104 to provide electromagnetic radiation that propagates through the patient's tissue and is detectable, e.g., using a communication interface (e.g., an antenna) of the separate medical device 50.

[0033] Figure 2 is a conceptual view of a leadless implantable medical device 106 or an intracardiac medical device and the anatomical structure of the patient's heart 8. One or more of the features described in relation to the device 106 can also be used with a leaded IMD, such as a leaded IMD 104 Figure 1 As used herein, "intracardiac" refers to a device that is configured to be implanted entirely within a patient's heart, e.g., to provide cardiac therapy.

[0034] The intracardiac device 10 can include a housing 30. The housing 30 can define a hermetically sealed internal cavity in which the internal components of the device 106, such as sensing circuitry, therapy delivery circuitry, control circuitry, memory, telemetry circuitry, other optional sensors, and a power source reside. The housing 30 can be formed from an electrically conductive material including titanium or a titanium alloy, stainless steel, MP35N (a non-magnetic nickel-cobalt-chromium-molybdenum alloy), platinum alloy, or other biocompatible metal or metal alloy. In other examples, the housing 30 can be formed from a non-conductive material including ceramic, glass, sapphire, silicone, polyurethane, epoxy, acetyl copolymer plastic, polyether ether ketone (PEEK), liquid crystal polymer, or other biocompatible polymer.

[0035] The device 106 can be described as a leadless implantable medical device. As used herein, "leadless" refers to a device that does not have a lead extending from the patient's heart 8. In other words, the lead of a leadless device can not extend from an exterior of the patient's heart to an interior of the patient's heart. Some leadless devices can be introduced through a vein, but once implanted, the device does not have or can not include any transvenous leads and can be configured to provide cardiac therapy without the use of any transvenous leads. In particular, the leadless VfA device does not use a lead to operably connect to an electrode in a ventricle when the housing of the device is positioned in an atrium. The leadless electrode can be coupled to the housing of the medical device without the use of a lead between the electrode and the housing.

[0036] The housing 30 can be described as extending in a generally cylindrical shape between a distal region 32 and a proximal region 34 to facilitate catheter delivery. In other embodiments, the housing 30 can be prismatic or any other shape in order to perform the functions and utilities described herein. The housing 30 can include a delivery tool interface member 26, for example, at the proximal end 34 for engagement with a delivery tool during implantation of the device 106. For example, the delivery tool interface member 26 can be used when advancing the device 106 toward a target implant region 4 using a delivery catheter 100 Figure 1 ) as described herein.

[0037] All or a portion of the housing 30 can be used as an electrode during cardiac therapy, e.g., in sensing and / or pacing. In the illustrated example, a housing-based electrode 24 is shown as circumscribing a proximal portion of the housing 30. When the housing 30 includes (e.g., is formed from) a conductive material such as a titanium alloy or other examples listed above, portions of the housing 30 can be electrically insulated by a non-conductive material such as a coating of parylene, polyurethane, silicone, epoxy, or other biocompatible polymer, leaving one or more discrete regions of the conductive material exposed to define the proximal housing-based electrode 24. When the housing 30 includes (e.g., is formed from) a non-conductive material such as a ceramic, glass, or polymeric material, a conductive coating or layer such as titanium, platinum, stainless steel, or alloys thereof can be applied to one or more discrete regions of the housing 30 to form the proximal housing-based electrode 24. In other examples, the proximal housing-based electrode 24 can be an assembly mounted or assembled onto the housing 30, such as a ring electrode. The proximal housing-based electrode 24 can be electrically coupled to the internal circuitry of the device 106, e.g., through the conductive housing 30 or an electrical conductor when the housing 30 includes a non-conductive material.

[0038] In the illustrated example, the housing-based electrode 24 can be positioned closer to the housing proximal region 34 than to the housing distal region 32, and thus can be described as a proximal housing-based electrode. However, in other examples, the housing-based electrode 24 can be located at other positions along the housing 30, e.g., relatively more distal than the position shown in FIG. 1. Figure 2 In the illustrated example, the housing-based electrode 24 can be positioned closer to the housing proximal region 34 than to the housing distal region 32, and thus can be described as a proximal housing-based electrode. However, in other examples, the housing-based electrode 24 can be located at other positions along the housing 30, e.g., relatively more distal than the position shown in FIG. 1.

[0039] At the distal region 32, the device 106 can include a distal fixation and electrode assembly 36, which can include one or more fixation members 20 in addition to one or more dart electrodes 12 of equal or unequal length. The device 106 as depicted includes a single dart electrode 12, which can include a shaft 40 extending distally away from the housing distal region 32, and can include one or more electrode elements such as a tip electrode element 42 at or near a free distal end region of the shaft 40. The tip electrode element 42 can have a conical or hemispherical distal tip having a relatively narrow tip diameter (e.g., less than about 1 millimeter (mm)) for penetrating and passing through tissue layers without the use of a sharp tip or needle-like tip having a sharp or beveled edge.

[0040] The shaft 40 of the dart electrode 12 can normally be a straight member and can be rigid. In other embodiments, the shaft 40 can be described as being relatively stiff, but still having limited flexibility (e.g., elastic or semi-rigid) in lateral directions. Further, the shaft 40 can be non-rigid to allow some lateral flexing to occur with cardiac motion. However, in a relaxed state, when not subjected to any external forces, the shaft 40 can maintain a straight positioning as shown to keep the tip electrode element 42 spaced apart from the housing distal end region 32 by at least the length or height 47 of the shaft 40. The dart electrode 12 can be configured to pierce one or more tissue layers to position the tip electrode element 42 at a desired tissue layer, such as within a ventricular myocardium. As such, the length or height 47 of the shaft 40 can correspond to the intended pacing site depth, and the shaft can have a relatively high compressive strength along its longitudinal axis to resist bending in lateral or radial directions when pressed against the implant region 4. If a second dart electrode 12 is employed, its length or height can not equal the intended pacing site depth, and can be configured to act as an indifferent electrode for delivering pacing energy to the tissue. A longitudinal axial force can be applied to the tip electrode element 42, for example, by applying a longitudinal “push” force to the proximal end 34 of the housing 30 to cause the dart electrode 12 to advance into the tissue within the target implant region 4. The shaft 40 can be longitudinally non-compressive. Further, the shaft 40 can be elastically deformable in lateral or radial directions when subjected to lateral or radial forces to allow temporary flexing, for example, with tissue motion, but can return to its normal straight positioning when the lateral forces are reduced. The shaft 40 can maintain a straight linear positioning as shown when not exposed to any external forces or only exposed to forces along its longitudinal central axis.

[0041] The one or more fixation members 20 can be described as having a normal curved positioning of one or more “tines.” The tines can be held in a distally extending positioning within a delivery tool. The distal tips of the tines can penetrate the heart tissue to a limited depth, and then elastically flex proximally back to the normal curved positioning (shown) upon release from the delivery tool. Further, the fixation members 20 can incorporate one or more aspects described in, for example, U.S. Patent No. 9,675,579 (Grubac et al.) issued June 13, 2017, and U.S. Patent No. 9,119,959 (Rys et al.) issued September 1, 2015.

[0042] In some examples, the distal fixation and electrode assembly 36 includes a distal housing-based electrode 22. In cases where the device 106 is used as a pacemaker for multi-chamber pacing (e.g., dual or triple chamber pacing) and sensing, the tip electrode element 42 can be used as a cathode electrode paired with the proximal housing-based electrode 24 acting as a return anode electrode. Alternatively, the distal housing-based electrode 22 can act as a return anode electrode paired with the tip electrode element 42 for sensing ventricular signals and delivering ventricular pacing pulses. In other examples, the distal housing-based electrode 22 can be a cathode electrode for sensing atrial signals and delivering pacing pulses to atrial cardiac muscle in the target implant region 4. When the distal housing-based electrode 22 acts as an atrial cathode electrode, the proximal housing-based electrode 24 can act as a return anode paired with the tip electrode element 42 for ventricular pacing and sensing, and can act as a return anode paired with the distal housing-based electrode 22 for atrial pacing and sensing.

[0043] As shown in this illustration, in some pacing applications, the target implant region 4 is along the atrial endocardium 18, generally under the AV node 15 and the His bundle 5. The dart electrode 42 can define a length or height 47 of the shaft 40 to penetrate the atrial endocardium 18 in the target implant region 4, pass through the central fibrous body 16, and into the ventricular myocardium 14 without penetrating the ventricular endocardial surface 17. When the length or height 47 of the dart electrode 12 is fully advanced into the target implant region 4, the tip electrode element 42 can rest or be positioned within the ventricular myocardium 14, and the distal housing-based electrode 22 can be positioned in close contact or in close proximity to the atrial endocardium 18. In various examples, the total combined length or height 47 of the tip electrode element 42 and the shaft 40 of the dart electrode 12 can be about 3 mm to about 8 mm. The diameter of the shaft 40 can be less than about 2 mm, and can be about 1 mm or less, or even about 0.6 mm or less.

[0044] The device 106 can include a motion detector 11 within the housing 30. The motion detector 11 can be used to monitor mechanical activity, such as atrial mechanical activity (e.g., atrial contractions) and / or ventricular mechanical activity (e.g., ventricular contractions). In some embodiments, the motion detector 11 can be used to detect right atrial mechanical activity. Non-limiting examples of the motion detector 11 include an accelerometer. In some embodiments, the mechanical activity detected by the motion detector 11 can be used to supplement or replace electrical activity detected by one or more of the electrodes of the device 106. For example, the motion detector 11 can be used in addition to or as an alternative to the proximal housing-based electrode 24.

[0045] The motion detector 11 can also be used for rate response detection or to provide a rate responsive IMD. Various techniques related to rate response can be described in U.S. Patent No. 5,154,170, entitled “Optimization for rate responsive cardiac pacemaker,” issued October 13, 1992 (Bennett et al.), and U.S. Patent No. 5,562,111, entitled “Method and apparatus for rate-responsive cardiac pacing,” issued October 8, 1996 (Yerich et al.).

[0046] Figure 3 is a three-dimensional perspective view of another example of a leadless implantable medical device 110 or intracardiac medical device that can be configured for single- or multi-chamber cardiac therapy (e.g., dual- or triple-chamber cardiac therapy). One or more of the features described with respect to the device 110 can also be used with a leaded IMD, such as the leaded IMD 104 Figure 1 ) and the like.

[0047] The device 110 can include a housing 130 having or defining an outer sidewall 135, shown as a cylindrical outer sidewall, extending from a housing distal end region 132 to a housing proximal end region 134. The housing 130 can enclose electronic circuitry configured to perform single- or multi-chamber cardiac therapy including atrial and ventricular cardiac electrical signal sensing and pacing of atrial and ventricular chambers. The delivery tool interface member 126 is shown on the housing proximal end region 134.

[0048] A distal fixation and electrode assembly 136 can be coupled to the housing distal end region 132. The distal fixation and electrode assembly 136 can include an electrically insulative distal member 172 coupled to the housing distal end region 132. The tissue-piercing electrode 112 extends away from the housing distal end region 132, and the plurality of non-tissue-piercing electrodes 122 can be directly coupled to the insulative distal member 172. The tissue-piercing electrode 112 extends in a longitudinal direction away from the housing distal end region 132, and can be coaxial with a longitudinal center axis 131 of the housing 130.

[0049] The tissue-piercing distal electrode 112 can include an electrically insulating shaft 140 and a tip electrode element 142. In some examples, the tissue-piercing distal electrode 112 also functions as a fixation member, and can include a helical shaft 140 and a distal cathode tip electrode element 142. The helical shaft 140 can extend from a shaft distal end region 143 to a shaft proximal end region 141, which can be directly coupled to the insulating distal member 172. The helical shaft 140 can be coated with an electrically insulating material, such as parylene or other examples listed herein, to avoid sensing or stimulating cardiac tissue along the shaft length. The tip electrode element 142 is at the shaft distal end region 143, and can function as a cathode electrode for delivering ventricular pacing pulses and sensing ventricular electrical signals using the proximal housing-based electrode 124 as a return anode when the tip electrode element 142 is advanced into ventricular tissue. The proximal housing-based electrode 124 can be a ring electrode that circumscribes the housing 130, and can be defined by the uninsulated portion of the longitudinal sidewall 135. Other portions of the housing 130 that do not function as electrodes can be coated with an electrically insulating material as described above in connection with the insulating distal member 172. Figure 2

[0050] Using two or more tissue-piercing electrodes (e.g., any type of tissue-piercing electrode) that penetrate into the LV myocardium can be used for local pacing capture, and can mitigate ventricular pacing spikes, affecting captured atrial tissue. In some embodiments, the multiple tissue-piercing electrodes can include two or more of a dart electrode (e.g., electrode 12 of the DIOGENES®) and a helical electrode (e.g., electrode 112). Non-limiting examples of multiple tissue-piercing electrodes include two dart electrodes, a helical electrode with a dart electrode extending therethrough (e.g., through the center), or a double-twisted helix. The multiple tissue-piercing electrodes can also be used for bipolar or multipolar pacing. Figures 1-2

[0051] In some embodiments, one or more tissue-piercing electrodes (e.g., any type of tissue-piercing electrode) that penetrate into the LV myocardium can be multipolar tissue-piercing electrodes. The multipolar tissue-piercing electrodes can include one or more electrically active elements and an electrical separation element, which can enable bipolar or multipolar pacing from the one or more tissue-piercing electrodes.

[0052] ​​The plurality of non-tissue-piercing electrodes 122 can be disposed along a perimeter of the insulating distal member 172 (e.g., disposed at a perimeter of the tissue-piercing electrodes 112. The insulating distal member 172 can define a distal-facing surface 138 of the device 110 and a circumferential surface 139 of the device 110 circumscribing the housing longitudinal sidewall 135. The non-tissue-piercing electrodes 122 can be formed of an electrically conductive material such as titanium, platinum, iridium, or alloys thereof. In the illustrated embodiment, six non-tissue-piercing electrodes 122 are radially spaced at equal distances along an outer perimeter of the insulating distal member 172. However, in some embodiments, two or more non-tissue-piercing electrodes 122 can be provided.

[0053] The non-tissue-piercing electrodes 122 can be discrete components each held within a respective recess 174 in the insulating member 172 sized and shaped to mate with the non-tissue-piercing electrodes 122. In other examples, the non-tissue-piercing electrodes 122 can each be an uninsulated exposed portion of a single-piece member mounted within or on the insulating distal member 172. An intermediate portion of the single-piece member that does not function as an electrode can be insulated by the insulating distal member 172 or can be coated with an electrically insulating coating, such as parylene, polyurethane, silicone, epoxy, or other insulating coating, if the intermediate portion is exposed to the ambient environment.

[0054] The at least one non-tissue-piercing electrode 122 can be positioned against, in close contact with, or in operative proximity to a surface of the heart tissue to deliver pulses and / or sense cardiac electrical signals generated by the patient's heart when the tissue-piercing electrodes 112 are advanced into the heart tissue. For example, one or more non-tissue-piercing electrodes 122 can be positioned in contact with right atrial endocardial tissue to pace and sense in the atrium when the tissue-piercing electrodes 112 are advanced into atrial tissue and through the central fibrous body until the distal tip electrode element 142 is positioned in direct contact with ventricular tissue, such as ventricular myocardium and / or a portion of the ventricular conduction system.

[0055] The non-tissue-piercing electrodes 122 can be coupled to therapy delivery circuitry and sensing circuitry enclosed by the housing 130 to collectively function as a cathode electrode for delivering atrial pacing pulses and sensing atrial electrical signals (e.g., P-waves) in combination with the proximal housing-based electrode 124 as a return anode. Switching circuitry contained in the sensing circuitry can be activated under the control of the control circuitry to couple one or more of the non-tissue-piercing electrodes to the atrial sense channel. The distal non-tissue-piercing electrodes 122 can be electrically isolated from one another so that each individual one of the electrodes 122 can be separately selected by switching circuitry contained in the therapy delivery circuitry to function individually or in combination with two or more of the electrodes 122 as an atrial cathode electrode. Switching circuitry contained in the therapy delivery circuitry can be activated under the control of the control circuitry to couple one or more of the non-tissue-piercing electrodes 122 to the atrial pacing circuitry. Two or more of the non-tissue-piercing electrodes 122 can be selected at a time to function as a multipoint atrial cathode electrode.

[0056] Certain ones of the non-tissue-piercing electrodes 122 selected for atrial pacing and / or atrial sensing can be selected based on atrial capture threshold testing, electrode impedance, P-wave signal strength in a cardiac electrical signal, or other factors. For example, a single non-tissue-piercing electrode 122 or any combination of two or more individual ones of the non-tissue-piercing electrodes can be selected to function as a cathode electrode that provides the best combination of low pacing capture threshold amplitude and relatively high electrode impedance to achieve reliable atrial pacing using minimal current consumption from the power source.

[0057] In some cases, the distally-facing surface 138 can uniformly contact the atrial endocardial surface when the tissue-piercing electrodes 112 anchor the housing 130 at the implant site. In such cases, all of the electrodes 122 can be selected together to form an atrial cathode. Alternatively, every other one of the electrodes 122 can be selected together to form a multipoint atrial cathode having a higher impedance that is still uniformly distributed along the distally-facing surface 138. Alternatively, a subset of one or more of the electrodes 122 along one side of the insulated distal member 172 can be selected to provide pacing at a desired site that achieves a lowest pacing capture threshold due to the relative location of the electrodes 122 to the atrial tissue subject to pacing.

[0058] In other instances, the distally-facing surface 138 can be oriented at an angle relative to an adjacent endocardial surface depending on the location and orientation of the tissue-piercing electrode 112 into the heart tissue. In such cases, one or more of the non-tissue-piercing electrodes 122 can be positioned in closer contact with the adjacent endocardial tissue than other non-tissue-piercing electrodes 122 that can be angled away from the endocardial surface. By providing a plurality of non-tissue-piercing electrodes along the perimeter of the insulative distal member 172, the angle of the tissue-piercing electrode 112 and the housing distal end region 132 relative to a heart surface, such as a right atrial endocardial surface, can not need to be substantially parallel. Anatomical and positioning differences can cause the distally-facing surface 138 to be angled or tilted relative to an endocardial surface, however, the plurality of non-tissue-piercing electrodes 122 distributed along the perimeter of the insulative distal member 172 can increase the likelihood of "good" contact between one or more electrodes 122 and adjacent heart tissue to facilitate acceptable pacing thresholds and reliable cardiac event sensing using at least a subset of the plurality of electrodes 122. Contact or fixation can not be required circumferentially along the entire perimeter of the insulative distal member 172.

[0059] The non-tissue-piercing electrodes 122 are shown as each including a first portion 122a extending along the distally-facing surface 138 and a second portion 122b extending along the circumferential surface 139. The first portion 122a and the second portion 122b can be continuous exposed surfaces such that the active electrode surface wraps around the perimeter edge 176 of the insulative distal member 172 joining the distally-facing surface 138 and the circumferential surface 139. The non-tissue-piercing electrodes 122 can include one or more of the electrodes along the distally-facing surface 138, one or more electrodes along the circumferential surface 139, one or more electrodes each extending along both the distally-facing surface 138 and the circumferential surface 139, or any combination thereof. The exposed surface of each of the non-tissue-piercing electrodes 122 can be flush with the respective distally-facing surface 138 and / or circumferential surface. In other examples, each of the non-tissue-piercing electrodes 122 can have a raised surface that protrudes from the insulative distal member 172. However, any raised surface of the electrodes 122 can define a smooth or rounded non-tissue-piercing surface.

[0060] The distal fixation and electrode assembly 136 can seal the distal end region of the housing 130 and can provide a basis on which the electrodes 122 are mounted. The electrodes 122 can be referred to as housing-based electrodes. The electrodes 122 can not be carried by a shaft or other extension that extends an active electrode portion away from the housing 130, such as a distal tip electrode element 142 that resides at a distal tip of a helical shaft 140 that extends away from the housing 130. Other examples of non-tissue-piercing electrodes presented herein that are coupled to a distal-facing surface and / or a circumferential surface of an insulating distal member include distal housing-based ring electrodes 22 Figure 2 ), distal housing-based ring electrodes that extend circumferentially around the assembly 36 Figure 2 ), button electrodes, other housing-based electrodes, and other circumferential ring electrodes. Any non-tissue-piercing electrode that is directly coupled to a distal insulating member, circumferentially coupled to a central tissue-piercing electrode, can be used as a cathode electrode for delivering pacing pulses to adjacent cardiac tissue, either individually, collectively, or in any combination. When a ring electrode is provided, such as the distal ring electrode 22 and / or the circumferential ring electrode, portions of the ring electrode can be electrically insulated by a coating to provide a plurality of distributed non-tissue-piercing electrodes along the distal-facing surface and / or the circumferential surface of the insulating distal member.

[0061] The non-tissue-piercing electrodes 122 and other examples listed above are intended to provide more reliable and effective atrial pacing and sensing compared to tissue-piercing electrodes provided along the distal fixation and electrode assembly 136. The atrial chamber wall is relatively thin compared to the ventricular chamber wall. A tissue-piercing atrial cathode electrode can extend too deep within the atrial tissue, resulting in unintentional continuous or intermittent capture of the ventricular tissue. The tissue-piercing atrial cathode electrode can cause interference with sensing atrial signals due to the ventricular signals having greater signal strength in the cardiac electrical signals received by the tissue-piercing atrial cathode electrode that are in physically closer proximity to the ventricular tissue. The tissue-piercing electrode 112 can be securely anchored into the ventricular tissue to stabilize the implant positioning of the device 110 and provide a reasonable certainty that the tip electrode element 142 senses and paces in the ventricular tissue while the non-tissue-piercing electrodes 122 reliably pace and sense in the atrium. When the device 110 is implanted in the target implant region 4, for example as shown in FIG. 1, the non-tissue-piercing electrodes 122 are positioned to pace and sense in the atrium 6 while the tissue-piercing electrode 112 is positioned to pace and sense in the ventricle 8. Figure 1The tip electrode element 142 can reach left ventricular tissue to pace the left ventricle, while the tissue-piercing electrode 122 provides pacing and sensing in the right atrium. The tissue-piercing electrode 112 can be in a length range of about 4 to about 8 mm from the distally facing surface 138 to reach left ventricular tissue. In some cases, the device 110 can achieve quad-chamber pacing by delivering atrial pacing pulses from the atrial pacing circuit through the non-tissue-piercing electrode 122 in the target implant region 4 to achieve dual atrial (right atrium and left atrium) capture, and by delivering ventricular pacing pulses from the ventricular pacing circuit through the tip electrode element 142 advanced into ventricular tissue from the target implant region 4 to achieve dual ventricular (right ventricle and left ventricle) capture.

[0062] Components described herein, such as one or more of a controller, circuitry, accelerometer, or sensor, can include a processor, such as a central processing unit (CPU), computer, logic array, or other device capable of directing data entry or exit from a medical device. The controller can include one or more computing devices or processing circuitry with memory, processing, and communication hardware. The controller can include circuitry for coupling the various components of the controller together or with other components operably coupled to the controller. The functions of the controller can be performed by hardware and / or as computer instructions on a non-transitory computer readable storage medium.

[0063] The processor of the controller can include any one or more of a microprocessor, a microcontroller, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), and / or equivalent discrete or integrated logic circuitry. In some examples, the processor can include multiple components, such as any combination of one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, and / or one or more FPGAs, as well as other discrete or integrated logic circuitry. The functions attributed to the controller or processor herein can be embodied in software, firmware, hardware, or any combination thereof. Although described herein as a processor-based system, alternative controllers can utilize other components, such as relays and timers, alone or in combination with microprocessor-based systems, to achieve the desired result.

[0064] In one or more embodiments, the example systems, methods, and other functionality can be implemented using one or more computers programmed with computer program code or logic to operate thus described. The program code and / or logic described herein can be applied to input data / information to perform the functions described herein and generate desired output data / information. The output data / information can be applied as input to one or more other devices and / or methods as described herein or as would be known in the art. In view of the above, it will be readily apparent that the controller functionality as described herein can be implemented in any manner known to those skilled in the art.

[0065] Figure 4 is a two-dimensional (2D) ventricular map 60 (e.g., top-down view) of a patient’s heart showing a left ventricle 62 and a right ventricle 64 in a standard 17-segment view. The map 60 includes a plurality of regions 68 corresponding to different regions of a human heart. As shown, the regions 68 are numbered 1-17 (which, for example, correspond to a standard 17-segment model of a human heart, to the 17 segments of the left ventricle of a human heart, etc.). The regions 68 of the map 60 can include an anteroseptal basal region 1, an inferoseptal basal region 2, an inferoseptal mid region 3, an infero basal region 4, an inferolateral basal region 5, an anterolateral basal region 6, an anteroseptal mid region 7, an anteroseptal inferoseptal region 8, an inferoseptal midinferoseptal region 9, an inferoseptal mid region 10, an inferolateral mid region 11, an anterolateral mid region 12, an anteroseptal apex region 13, an anteroseptal apex region 14, an inferoseptal apex region 15, an inferolateral apex region 16, and an apex region 17. Also shown are the inferoseptal and anteroseptal regions of the right ventricle 64, as well as the right bundle branch (RBB) and the left bundle branch (LBB).

[0066] In some embodiments, any of the tissue-piercing electrodes of the present disclosure can be implanted in a basal region and / or a septal region of a left ventricle myocardium of a patient’s heart. In particular, the tissue-piercing electrodes can be implanted from a Koch’s triangle region of a right atrium through a right atrial endocardium and central fibrous body.

[0067] Once implanted, the tissue-piercing electrodes can be positioned in a target implant region 4( Figure 1 ) such as a basal and / or septal region of a left ventricle myocardium. With reference to the map 60, the basal region includes one or more of: the anteroseptal basal region 1, the inferoseptal basal region 2, the inferoseptal mid region 3, the infero basal region 4, the anteroseptal mid region 7, the anteroseptal inferoseptal region 8, the inferoseptal midinferoseptal region 9, and the inferoseptal mid region 10. With reference to the map 60, the septal region includes one or more of: the anteroseptal basal region 2, the anteroseptal inferoseptal region 3, the anteroseptal mid region 8, the inferoseptal midinferoseptal region 9, and the anteroseptal apex region 14.

[0068] In some embodiments, when implanted, the tissue-piercing electrodes can be positioned in a basal septal region of a left ventricle myocardium. The basal septal region can include one or more of the anteroseptal basal region 2, the inferoseptal mid region 3, the anteroseptal mid region 8, and the inferoseptal midinferoseptal region 9.

[0069] In some embodiments, when implanted, the tissue-piercing electrodes can be positioned in a high inferior / posterior basal septal region of the left ventricular myocardium. The high inferior / posterior basal septal region of the left ventricular myocardium can include a portion of at least one of the basal inferior septal region 3 and the mid-inferior septal region 9. For example, the high inferior / posterior basal septal region can include the region 66 generally shown as a dashed boundary. As shown, the dashed boundary represents an approximate estimate of where the high inferior / posterior basal septal region is located, and can take slightly different shapes or sizes depending on the particular application. Without being bound by any particular theory, intraventricular synchronous pacing and / or activation can result from stimulating the high septal ventricular myocardium due to functional electrical coupling between subendocardial Purkinje fibers and the ventricular myocardium.

[0070] Figure 5A FIG. 1 is various views of one example of an embodiment of a delivery catheter 100 that can be used with the elongated element 102. Figure 1 FIG. 2 is a side view showing a delivery catheter 200 that can be used with the elongated element 102. Figure 5A FIG. 3 is a top view showing the delivery catheter 200. Figure 5B FIG. 4 is a cross-sectional view taken along the line C-C shown in FIG. 3. Figure 5C FIG. 5 is a cross-sectional view taken along the line C-C shown in FIG. 3. Figure 5B

[0071] The elongated element 102 can be any suitable device for insertion into the CS. For example, the elongated element 102 can be a guidewire or a catheter. In some embodiments, the elongated element 102 can be steerable.

[0072] Further, the elongated element 102 can be anchorable in the CS. Anchorable in the CS means that the elongated element 102 includes any suitable mechanism for maintaining the elongated element within the CS for any period of time. In some embodiments, the elongated element 102 can include an anchorable balloon or an anchorable side coil to facilitate stable anchoring in the CS after insertion of the elongated element into the CS, which can provide a reliable reference for delivery of a device to the target implant region 4. Figure 1 The elongated element 102 can be inserted into the CS any suitable distance to facilitate use of the elongated element as a physical reference. The elongated element 102 can remain in the CS or be removed after implanting a device at the target implant region 4.

[0073] In addition to providing a physical reference to the CS, the elongated element 102 can provide other functions. In some embodiments, the elongated element 102 can remain in the CS and can be used as a cardiac therapy system 2. Figure 1 ​For example, the elongated member 102 can include one or more electrodes to facilitate cardiac therapy. In some embodiments, the elongated member 102 can be described as a therapy catheter for sensing or pacing, such as an electrophysiology (EP) catheter. For example, an EP catheter can be used to assess electrical patterns in the heart and then perform ablation.

[0074] The delivery catheter 200 includes an elongated body including a first portion 202 and a second portion 204, which can be integrally formed from a single piece of material or separately formed and coupled together. The first portion 202 and the second portion 204 can extend from a proximal region 210 to a respective first distal region 206 and a respective second distal region 208. As illustrated, the proximal region 210 can represent a proximal end region of the delivery catheter 200 or an intermediate region that is not a proximal end region of the delivery catheter 200. The delivery catheter 200 can be any suitable length to facilitate the techniques of the present disclosure. The first portion 202 and the second portion 204 can each extend longitudinally adjacent or side-by-side one another.

[0075] Each portion can define a lumen. A first lumen 212 defined by the first portion 202 can extend from the proximal region 210 to the first distal region 206. A second lumen 214 defined by the second portion 204 can extend from the proximal region 210 to the second distal region 208.

[0076] The first lumen 212 in the first distal region 206 can be described as extending along a first axis 216. The second lumen 214 in the second distal region 208 can be described as extending along a second axis 218. The first axis 216 and the second axis 218 form or define an angle 220 such that when the first axis is pointed in the CS, the second axis is pointed at the LV apex of the heart of the patient. For example, when the elongated member 102 is at least partially advanced through the first lumen 212 along the first axis 216 and inserted into and optionally anchored in the CS, the second axis can be pointed at the LV apex. When the elongated member 102 is advanced through the first lumen 212 into the CS and the second axis 218 is pointed at the LV apex, a device advanced through the second lumen 214 can be directed to an implantation site in the Koch triangle region.

[0077] Any suitable angle 220 can be used. The angle 220 can depend on the physiology of the particular patient. In some embodiments, the angle 220 can be at least about 30, 40, 50, 60, or even 70 degrees. In some embodiments, the angle 220 can be at most about 110, 100, 90, 80, or even 70 degrees. For example, the angle 200 can be in a range of about 50 degrees to about 90 degrees. As used herein, “at most” can be used interchangeably with “less than or equal to,” and “at least” can be used interchangeably with “greater than or equal to.”

[0078] In one or more embodiments, a different angle can be defined between a first vector normal to the CS port of the patient's heart and a second vector from the CS port to the LV apex, the angle can be at least about 30, 40, 50, 60, or even 70 degrees, or at most about 110, 100, 90, 80, or even 70 degrees.

[0079] In the illustrated embodiment, the proximal region 210 of the second portion 204 is aligned with the first axis 216, and the second distal region 208 is aligned with the second axis 218. A curved region 222 of the second portion 204 can be defined between the second distal region 208 and the proximal region 210. The curved region 222 provides a transition between the proximal region 210 and the distal region that can be more gradual than illustrated in some embodiments. The first portion 202 can extend relatively linearly from the proximal region 210 to the first distal region 206 along the first axis 216.

[0080] In some embodiments, the second distal region 208 can also be curved. The alignment of the second distal region 208 can be defined by the distal most segment of the distal region, or specifically by the orientation of the medical device extending through the second lumen 214 in the distal region.

[0081] The angle 220 can be described as fixed or deflectable (e.g., elastic). When the angle 220 is deflectable, any suitable mechanism can be used to control, define, or change the angle. For example, in some embodiments, a pull wire can be used to define the deflectable angle 220. In general, the delivery catheter 200 can be formed from any suitable flexible or semi-flexible material for delivering the device to the patient's heart. In some embodiments, the angle 220 can be defined as a fixed angle when the material forming some or all of the delivery catheter 200 is sufficiently stiff to prevent deviation from the target implant region 4 during delivery. The material forming the second distal region 208 or the curved region 222 of the second portion 204 can be the same or different than the material forming the remainder of the second portion, such as the proximal region 210 or the first portion 202. In some embodiments, the material forming the second distal region 208 or the curved region 222 can be stiffer (e.g., have a higher Shore hardness) than the material forming the proximal region 210 or the first portion 202. For example, the second distal region 208 or the curved region 222 can be formed from a material of about 55D, and the proximal region 210 or the first portion 202 can be formed from a material of about 35D or 40D.

[0082] In some embodiments, the second portion 204 can include a braided structure to define the second lumen 214 to facilitate shape retention. In some embodiments, the second portion 204 can use a greater wall thickness than the first portion 202 to facilitate shape retention.

[0083] Any suitable technique can be used to form the delivery catheter 200. In some embodiments, the delivery catheter 200 can be made from a single extrusion. In other embodiments, the delivery catheter 200 can be made using three-dimensional (3D) machine printing. Any suitable material, such as an elastomer, can be used to form the delivery catheter 200. Non-limiting examples of materials that can be used to form the delivery catheter 200 include one or more of a polyether block amide (such as PEBAX), a polyurethane, or a nylon.

[0084] The angled or curved region of the second portion 204 can be straightened as the delivery catheter 200 is guided to the patient's heart. In some embodiments, a dilator tracked over a guidewire can be inserted into the second lumen 214 and into the curved region 222 and the second distal region 208 to straighten the second portion 204. Once the second distal region 208 reaches the patient's heart, the dilator and guidewire can be retracted and removed to allow the second portion 204 to shape and form the angle 220 with the first portion 202.

[0085] In some embodiments, the first distal region 206 can extend into the CS (e.g., as opposed to only guiding the elongated member 102 into the CS). In the illustrated embodiment, the first portion 202 extends more distally than the second portion 204, such that the first distal region 206 is further along the first axis 216 than the second distal region 208, which can facilitate insertion and anchoring in the CS. The first portion 202 can extend beyond the second portion 204 by any suitable amount to facilitate insertion and anchoring in the CS. For example, the first portion 202 can extend at least one inch beyond the second portion 204 or can extend up to two inches beyond.

[0086] In other embodiments, the first distal region 206 can extend toward the CS but can not extend into the CS. In one embodiment, the first distal region 206 can not extend more distally than the second distal region 208 or the curved region 222.

[0087] The delivery catheter 200 can be a passive or active device. In the illustrated embodiment, the delivery catheter 200 can be described as an active device comprising one or more electrodes 224. The electrodes 224 can be coupled to a second distal region 208 of the second portion 204 and are used to map atrial activation prior to implantation of the device into the target implantation region 4. One or more electrodes 224 can be electrically coupled to the proximal end of the delivery catheter 200 using a conductor (not shown) extending through the proximal region 210. In the illustrated embodiment, four electrodes 224 are arranged along the distal side of the second portion 204 around an opening 226 at the end of the second lumen 214. The electrodes 224 can be positioned against the Koch triangle region of the RA to map atrial activation prior to implantation of the device from the second lumen 214 through the opening 226.

[0088] The first cavity 212 and the second cavity 214 can have the same or different sizes to accommodate various types of devices. For example... Figure 5C As shown, a first cavity 212 may define a first width 232, and a second cavity 214 may define a second width 234. In some embodiments, one or both of the first width 232 and the second width 234 may be described as a first diameter and a second diameter, respectively. Figure 5C As shown, in some embodiments, the second width 234 may be larger than the first width 232. For example, the first width 232 may be sized to accommodate a guidewire (e.g., the inner diameter of a 0.038-inch guidewire), and the second width 234 may be sized to accommodate a pacing lead (e.g., the inner diameter of a 7 French lead). In other embodiments, such as when configured to insert a catheter and a lead of similar size into a corresponding lumen, the first width 232 and the second width 234 may be the same or similar (e.g., see [link to relevant documentation]). Figure 6 ).

[0089] Figure 6 A delivery catheter 100 including an interlocking assembly is shown. Figure 1 A cross-sectional view of another example of the implementation of the delivery catheter 300. The delivery catheter 300 can be similar in many respects to the delivery catheter 200. Figure 5A-C), except that the delivery catheter 300 can include an interlocking assembly including an external channel 342 defined in the first portion 302 and a protrusion 344 configured to be received in the channel extending laterally from the second portion 304. The channel 342 can slidably guide the second portion 304 along the length of the first portion 302. The interlocking assembly can allow the first portion 302 and the second portion 304 to be translatable relative to one another. In some embodiments, the first portion 302 can be inserted independently of the second portion 304. In other embodiments, the channel 342 can be defined in the second portion 304 and the protrusion 344 can extend laterally from the first portion 302.

[0090] As used herein with respect to a delivery catheter, the term "lateral" refers to a direction away from a longitudinal axis, such as the first axis defined by the first portion 302 or the second axis defined by the second portion 304. In some embodiments, lateral can be a direction orthogonal to the longitudinal axis.

[0091] The channel 342 and the complementary protrusion 344 can each have any suitable depth and complementary height, respectively, to facilitate guidance. In some embodiments, the depth or height can be at least about 0.5, 1, 1.5, or even 2 mm. In some embodiments, the depth or height can be at most about 3, 2.5, 2, 1.5, or even 1 mm. For example, the depth or height can be in a range of about 1 mm to about 2 mm.

[0092] The channel 342 can extend along the first portion 302 for any suitable length. In some embodiments, the channel 342 extends along the entire length of the first portion 302. In some embodiments, the channel 342 can include a distal end that stops short of the distal end of the first portion 302.

[0093] The protrusion 344 can extend along the second portion 304 for any suitable length. In some embodiments, the protrusion 344 is disposed at one or more discrete locations on the elongate body of the second portion 304. For example, each protrusion 344 can have a length of at most about 1, 2, 3, or even 4 centimeters (cm) along the length of the second portion 304. In one embodiment, the protrusion 344 is disposed at only one discrete location. In some embodiments, the protrusion 344 extends along a greater length of the second portion 304. For example, the length of the protrusion 344 can be at least about 1, 2, 3, or even 4 cm up to the entire length of the second portion 304. The protrusion 344 can extend continuously or discretely.

[0094] The protrusion 344 can be positioned at any suitable location along the second portion 304. In some embodiments, a discrete protrusion 344 can be positioned in a distal region, a curved region, a proximal region, a non-curved region, or between any of these regions.

[0095] Figure 7 is a flowchart illustrating one example of a method 400 of using a delivery catheter of the present disclosure. The method 400 can include advancing a first distal end region of a delivery catheter or dual-lumen catheter toward the CS 402. In some embodiments, the first distal end region can be inserted into the CS. The method 400 can also include orienting a second distal end region of the delivery catheter toward the Koch’s triangle region 404. Orienting the delivery catheter can involve twisting to rotate the second portion around the first portion until an end of the second portion points toward the LV apex, for example, when the first distal end region is fully advanced toward the CS. As used herein with respect to a delivery catheter, the term “twist” refers to applying a rotational force or torque to the delivery catheter. The method 400 can also include implanting a medical device into the Koch’s triangle region through the delivery catheter 406. In some embodiments, the implantable medical device can be advanced through a second lumen of the delivery catheter that extends through the second distal end region. The implantable medical device can be secured to an implant site or target implant region in the Koch’s triangle.

[0096] Generally, the delivery catheter can be advanced over an elongated element, such as a guidewire or another catheter, toward the CS using a first lumen that extends through a first distal end region of the delivery catheter.

[0097] Figure 8 is a flowchart illustrating one example of a method 410 of using a guidewire for an elongated element and a monolithically formed delivery catheter having a first lumen and a second lumen. The method 410 can include advancing a cannulation catheter into the CS 412. Specifically, the cannulation catheter can be inserted into the subclavian vein over a guidewire and through the superior vena cava (SVC) to enter the RA, and then used to cannulate the CS. The guidewire can be advanced into the CS through the cannulation catheter.

[0098] In some embodiments, the guidewire can be anchored in the CS. For example, the guidewire can be advanced about 1, 2, 3, 4, 5, or even 6 cm into the CS and even into the great cardiac vein (GCV) to anchor the guidewire in the CS. The method 410 can include removing the cannulation catheter and leaving the guidewire in place 414.

[0099] The method 410 can also include advancing a delivery catheter or dual-lumen catheter over the guidewire toward the CS using a first lumen of the delivery catheter 416. The delivery catheter can be tracked along the guidewire until the delivery catheter prevents further advancement. For example, a portion forming the second lumen can be prevented from further advancement by the CS ostium.

[0100] Method 410 can include orienting 418 the second lumen of the delivery catheter toward the Koch triangle region of the patient's heart. In some embodiments, the delivery catheter is twisted such that a second portion of the delivery catheter defining the second lumen, which can have a fixed or deflectable curve, contacts tissue in the target implant location in the Koch triangle region.

[0101] Method 410 can also include implanting 420 a device into the Koch triangle region through the second lumen. The second lumen can direct the device from the implant location toward the LV apex, which can facilitate implanting the device for VfA cardiac therapy. Once in place, the device can be fixed at the implant location. Method 410 can include withdrawing 422 the delivery catheter. For example, the delivery catheter can be cut and retracted.

[0102] Figure 9 is a flowchart illustrating another example of a method 430 using a therapy catheter for an elongate element, such as an EP catheter, and a unitarily formed delivery catheter defining a first lumen and a second lumen. Method 430 can include advancing 432 the therapy catheter into the CS. In particular, the therapy catheter can be inserted over a guidewire into the subclavian vein and through the SVC to enter the RA, and then used to cannulate the CS. The therapy catheter can be anchored in the CS. For example, the therapy catheter can be advanced several centimeters into the CS and even into the great cardiac vein (GCV) to anchor the therapy catheter in the CS. The guidewire can also be advanced into the CS through the therapy catheter in a similar manner.

[0103] Method 430 can also include advancing 434 the delivery catheter or dual lumen catheter over the therapy catheter toward the CS using the first lumen of the delivery catheter. The delivery catheter can be tracked along the therapy catheter until the delivery catheter prevents further advancement. For example, a portion forming the second lumen can be stopped from further advancement by the CS ostium.

[0104] Method 430 can include orienting 436 the second lumen of the delivery catheter toward the Koch triangle region of the patient's heart. In some embodiments, the delivery catheter is twisted such that a second portion of the delivery catheter defining the second lumen, which can have a fixed or deflectable curve, contacts tissue in the target implant location in the Koch triangle region.

[0105] Method 430 can also include implanting 438 a device into the Koch triangle region through the second lumen. The second lumen can direct the device from the implant location toward the LV apex, which can facilitate implanting the device for VfA cardiac therapy. Once in place, the device can be fixed at the implant location. Method 430 can include withdrawing 440 the delivery catheter. For example, the delivery catheter can be cut and retracted. The therapy catheter can be left in or withdrawn. For example, the guidewire can also be withdrawn when the delivery catheter is withdrawn.

[0106] Figure 10 is a flowchart illustrating another example of a method 450 of using a guidewire for an elongated element and a split-formed delivery catheter having a translatable first portion and a second portion. The method 450 can include advancing a first portion of the delivery catheter over the guidewire 452. Specifically, the first portion defining a first lumen can be inserted over the guidewire into the subclavian vein and through the SVC to enter the RA, and then used to cannulate the CS. The guidewire can be advanced through the first lumen into the CS.

[0107] The method 450 can include translatable coupling the first portion and the second portion 454 using an interlocking assembly, such as a channel and a complementary protrusion. Specifically, the protrusion of the second portion can be inserted into the channel of the first portion.

[0108] The method 450 can include advancing a second portion defining a second lumen over the first portion toward the CS 456. The protrusion of the second portion can be tracked along the channel of the first portion until the second portion prevents further advancement. For example, the second portion forming the second lumen can be stopped from further advancement by the CS ostium.

[0109] The method 450 can include orienting the second lumen of the second portion toward the Koch triangle region of the heart of the patient 458. In some embodiments, the delivery catheter is twisted such that the second portion of the delivery catheter, which can have a fixed or deflectable curve, is in contact with tissue in the target implant location in the Koch triangle region.

[0110] The method 450 can also include implanting a device into the Koch triangle region through the second lumen 460. The second lumen can direct the device from the implant location toward the LV apex, which can facilitate implanting the device for VfA cardiac therapy. Once in place, the device can be fixed at the implant location. The method 450 can include withdrawing the delivery catheter 462. For example, the delivery catheter can be cut and retracted.

[0111] Illustrative Embodiments

[0112] While the disclosure is not so limited, an understanding of the various aspects of the disclosure will be obtained by consideration of the detailed description that follows, with reference to one particular example of illustrative embodiments. Various modifications to these illustrative embodiments and additional embodiments of the disclosure will be apparent to those of ordinary skill in the art in view of the detailed description that follows.

[0113] In illustrative embodiment Al, an implantable medical device delivery system includes an anchorable elongated element that is anchorable in a coronary sinus (CS) of a heart of a patient. The system also includes a delivery catheter having an elongated body with a first portion defining a first lumen and a second portion defining a second lumen. The first lumen, located in a first distal region of the first portion, extends along a first axis, and the second lumen, located in a second distal region of the second portion, extends along a second axis that forms an angle with the first axis. When the anchorable elongated element is advanced through the first lumen into the CS, the second axis is directed toward a left ventricular (LV) apex of the heart of the patient.

[0114] In illustrative embodiment A2, the system of any A illustrative embodiment, further including a delivery catheter configured such that, when the elongated element is advanced through the first lumen into the CS and the second axis is directed toward the LV apex, an implantable medical device advanced through the second lumen is directed to an implant site in a Koch triangle region of the heart of the patient.

[0115] In illustrative embodiment A3, the system of illustrative embodiment A2, further including the implantable medical device. The implantable medical device includes at least one electrode for providing cardiac therapy to or sensing electrical activity of a right atrium (RA) or LV of the heart of the patient.

[0116] In illustrative embodiment A4, the system of any A illustrative embodiment, further including the implantable medical device as a leaded implantable medical device.

[0117] In illustrative embodiment A5, the system of any A illustrative embodiment, further including the angle as a fixed angle.

[0118] In illustrative embodiment A6, the system of any A illustrative embodiment, further including the elongated element as a guidewire or catheter.

[0119] In illustrative embodiment A7, the system of any A illustrative embodiment, further including the elongated element having one or both of an anchorable balloon and an anchorable side helix.

[0120] In illustrative embodiment A8, the system of any A illustrative embodiment, further including the elongated element having one or more electrodes.

[0121] In illustrative embodiment A9, the system of any A illustrative embodiment, further comprising one or more electrodes coupled to the second distal region of the second portion to map atrial activation.

[0122] In illustrative embodiment A10, the system of any A illustrative embodiment, further comprising a second distal region that is more flexible than one or both of a proximal region of the elongate body and the elongate element.

[0123] In illustrative embodiment A11, the system of any A illustrative embodiment, further comprising a second distal region that is distal relative to the first distal region with respect to the first axis.

[0124] In illustrative embodiment A12, the system of any A illustrative embodiment, further comprising an angle of at most 90 degrees.

[0125] In illustrative embodiment B1, a delivery catheter comprises a first portion that is advanceable into a coronary sinus (CS) of a heart of a patient, the first portion having an elongate body that defines a first lumen and an exterior passageway. A region of the first portion that is adjacent to a CS ostium of the heart of the patient extends along a first axis when the first portion is advanced into the CS. The device comprises a second portion having an elongate body that defines a second lumen and having a laterally extending protrusion that is configured to be received in the exterior passageway of the first portion so as to slidably guide the second portion along a length of the first portion. A distal region of the second portion extends along a second axis that forms a fixed angle with the first axis when the protrusion is engaged in the passageway, such that the second axis is directed toward a left ventricular (LV) apex of the heart of the patient when the first portion is advanced into the CS.

[0126] In illustrative embodiment B2, the system of any B illustrative embodiment, further comprising an implantable medical device, the implantable medical device that is advanced through the second lumen being directed to an implantation site in a region of the Koch triangle of the heart of the patient when the first portion is advanced into the CS and the second axis is directed toward the LV apex.

[0127] In illustrative embodiment B3, the system of illustrative embodiment B2, further comprising the implantable medical device. The implantable medical device comprises at least one electrode to provide cardiac therapy to or to sense electrical activity of a right atrium (RA) or the LV of the heart of the patient.

[0128] In illustrative embodiment B4, the system of any B illustrative embodiment, further comprising a protrusion disposed at a discrete location on the elongated body of the second portion.

[0129] In illustrative embodiment B5, the system of any B illustrative embodiment, further comprising one or more electrodes coupled to the distal region of the second portion to map atrial activation.

[0130] In illustrative embodiment CI, a method of delivering an implantable medical device includes advancing a first distal region of a first portion of a dual-lumen catheter toward a coronary sinus (CS) of a heart of a patient. The first portion defines a first lumen, and the first distal region extends along a first axis. The method includes orienting a second distal region of a second portion of the dual-lumen catheter toward a Koch triangle region of the heart of the patient. The second portion defines a second lumen, and the second distal region extends along a second axis that forms an angle with the first axis such that when the first distal region is fully advanced toward the CS, the second axis is pointed toward a left ventricular (LV) apex of the heart of the patient.

[0131] In illustrative embodiment C2, the method of any C illustrative embodiment, further comprising rotating the dual-lumen catheter to point the second axis toward the LV apex; advancing an implantable medical device through the second lumen of the dual-lumen catheter; and securing the implantable medical device to an implant site in the Koch triangle region of the heart of the patient.

[0132] In illustrative embodiment C3, the method of any C illustrative embodiment, further comprising advancing an elongated element into the coronary sinus (CS) of the heart of the patient. When the elongated element is advanced into the CS, a portion of the elongated element adjacent to a CS ostium extends along the first axis. The method includes advancing the dual-lumen catheter over the elongated element using the first lumen to direct the first distal region toward the CS.

[0133] In illustrative embodiment C4, the method of illustrative embodiment C3, further comprising the elongated element having a guidewire, and the method further comprises advancing a cannulation catheter into the CS of the heart of the patient; advancing the guidewire through the cannulation catheter into the CS; and withdrawing the cannulation catheter.

[0134] In illustrative embodiment C5, the method according to any C illustrative embodiment, further comprising a first portion defining an outer channel; and a second portion having a laterally extending protrusion configured to be received in the outer channel. The method comprises advancing the second portion guided by the first portion using the protrusion in engagement with the outer channel; orienting the second portion with the second axis pointing towards the LV apex; advancing an implantable medical device through the second lumen of the dual lumen catheter; and securing the implantable medical device to an implant site in the Koch triangle region of the heart of the patient.

[0135] Accordingly, various embodiments of a delivery system for VFA cardiac therapy are disclosed. The techniques of the present disclosure provide a delivery catheter that uses the CS as a physical reference to stabilize an implantable medical device in the proper position and orientation for implantation at a target implant region, particularly in the Koch triangle region, to deliver pacing to the LV.

[0136] It should be understood that various aspects disclosed herein can be combined in different combinations than the combinations expressly presented in the description and accompanying drawings. It should also be understood that certain actions or events can be performed in different orders, added, modified, or omitted from the above-described processes or methods without departing from the described technology. Furthermore, although certain aspects of the present disclosure are described as being performed by a single module or unit for purposes of clarity, it should be understood that the techniques of the present disclosure can be performed by a combination of units or modules associated with, for example, a medical device.

[0137] In one or more examples, the described techniques can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media can include non-transitory computer-readable media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

[0138] Instructions can be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term "processor," as used herein can refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. Also, the described techniques can be implemented in a computer system that includes one or more circuits or logic elements.

[0139] All references and publications cited herein are incorporated herein by reference in their entirety unless otherwise indicated.

[0140] Unless otherwise defined, all scientific and technical terms used herein have the meanings that are commonly understood by one of ordinary skill in the art. The definitions provided herein are to facilitate understanding of certain terms used frequently herein and are not meant to limit the scope of the present disclosure.

[0141] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term "completely" or "about.” Thus, unless otherwise indicated, the numerical parameters set forth in the foregoing description and associated claims are approximations. Variations to these numerical parameters are meant to be within disclosed ranges.

[0142] Numerical ranges recited herein are inclusive of the numbers within the range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5) and any range within the range. In this document, the terms “up to” or “no more than” a number (e.g., up to 50) include the number (e.g., 50), and the terms “at least” or “no less than” a number (e.g., no less than 5) include the number (e.g., 5).

[0143] Terms relating to orientation, such as “proximal,” “distal,” “lateral,” and “end,” are used to describe the relative positioning of components and are not meant to limit the orientation of the embodiments under consideration.

[0144] The terms “coupled” or “connected” refer to elements being either directly attached to one another (in direct contact with one another) or indirectly attached (having one or more elements between and attaching the two elements). Both terms can be modified by “operatively” and “operably,” which can be used interchangeably, to describe that the coupling or connection is configured to allow the components to interact to perform a function.

[0145] As used herein, the term “configured to” can be used interchangeably with the term “adapted to” or “structured to,” unless the context of the present disclosure clearly indicates otherwise.

[0146] The singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the context clearly dictates otherwise.

[0147] The term“or” is generally employed in its inclusive sense, for example, “and / or,” unless the context clearly indicates otherwise.

[0148] The term“and / or” means one or all of the listed elements or a combination of any two or more of the listed elements.

[0149] The phrases“at least one of,”“comprising at least one of,” and“one or more of’ followed by a list of two or more items mean any one of the items in the list and

[0150] As used herein,“have,”“having,”“include,”“including,”“include

[0151] References to“one embodiment,”“an embodiment,”“certain embodiments,” or“some embodiments,” etc., mean that a particular feature, configuration, composition, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Thus, the appearances of such phrases in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, configurations, compositions, or characteristics can be combined in any suitable manner in one or more embodiments.

Claims

1. An implantable medical device delivery system, comprising: An elongated element capable of being anchored in the coronary sinus (CS) of a patient's heart; as well as A delivery catheter comprising an elongated body having a first portion defining a first lumen and a second portion defining a second lumen, wherein the first lumen, located in a first distal region of the first portion, extends along a first axis, and the second lumen, located in a second distal region of the second portion, extends along a second axis forming an angle with the first axis, wherein the second axis points toward the apex of the left ventricle (LV) of the patient's heart as the anchorable elongated element is advanced through the first lumen into the coronary sinus (CS). The delivery catheter is configured such that when the elongated element is advanced through the first lumen into the coronary sinus (CS) and the second axis is directed toward the apex of the left ventricle (LV), the second lumen is configured to guide the implantable medical device advanced through the second lumen to the implantation site in the Koch's triangle region of the patient's heart.

2. The system of claim 1, further comprising the implantable medical device including at least one electrode for providing cardiac therapy to the right atrium (RA) or left ventricle (LV) of the patient's heart or for sensing electrical activity of the right atrium (RA) or left ventricle (LV) of the patient's heart.

3. The system of claim 2, wherein the implantable medical device includes an implantable medical device with leads.

4. The system according to claim 1, wherein the angle is a fixed angle.

5. The system of claim 1, wherein the elongated element comprises a guidewire or a catheter.

6. The system of claim 1, wherein the elongated element comprises one or both of an anchorable balloon and an anchorable side spiral.

7. The system of claim 1, wherein the elongated element comprises one or more electrodes.

8. The system of claim 1, wherein one or more electrodes are coupled to the second distal region of the second portion to map atrial activation.

9. The system of claim 1, wherein the second distal region is more flexible than one or both of the proximal region of the elongated body and the elongated element.

10. The system of claim 1, wherein the second distal region is located distal to the first distal region relative to the first axis.

11. The system of claim 1, wherein the angle is at most 90 degrees.

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