Delivery system for a medical device

Abstract

A medical system including a device receptacle configured to hold an implantable medical device (IMD) (102) within a receptacle volume. The device receptacle is supported by a delivery catheter configured to position the device receptacle within an anatomical volume of a patient, such as a heart chamber. A device tether (120) including a conductive tether supports a tether head (128) configured to engage with and / or disengage from the IMD. A tether electrode (129) is configured to receive an intrinsic electrical signal produced by the heart of the patient. The device tether is configured to conduct the intrinsic electrical signal from the tether electrode to processing circuitry extracorporeal to the patient using the conductive tether.

Description

Atty Ref. No: A0011305WO01 DELIVERY SYSTEM FOR A MEDICAL DEVICE

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No.63 / 611,599, filed December 18, 2023, the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] This disclosure is related to systems for delivery and / or retrieval of implantable medical devices. BACKGROUND

[0003] Various types of implantable medical devices have been implanted for treating or monitoring one or more conditions of a patient. Such implantable medical devices may be adapted to allow medical devices to monitor and / or treat conditions or functions relating to heart, muscle, nerve, brain, stomach, endocrine organs or other organs and their related functions. The implantable medical devices may be implanted at target locations selected to detect a physiological condition of the patient and / or deliver one or more therapies. For example, implantable medical devices may be delivered to locations within an atrium or ventricle of a heart to sense intrinsic cardiac signals and deliver pacing or antitachyarrhythmia shock therapy.

[0004] Some implantable medical devices are sized to be completely implanted within one of the chambers of the heart and / or another anatomical volume of the patient to detect a physiological condition and / or deliver one or more therapies. Such implantable medical devices may utilize delivery and / or retrieval systems to allow a clinician to navigate the implantable medical device (e.g., through vasculature of the patient) to the target location, and / or to retrieve the implantable medical device from the patient. In some examples, the implantable medical device may include one or more anchoring components intended to engage tissues at the target location (e.g., for implantation) and / or disengage from tissue at the target location (e.g., for retrieval). SUMMARY

[0005] The disclosure describes a medical system configured to deliver, position, retrieve, and / or otherwise re-orient an implantable medical device (“IMD”) within anAtty Ref. No: A0011305WO01 anatomical volume (e.g., a chamber of a heart) within a patient. The medical system includes a device tether including a conductive tether supporting a tether head configured to engage with and / or disengage from the IMD. The medical system may further include a delivery catheter supporting a device receptacle configured to hold the IMD within a receptacle volume. The conductive tether extends through a lumen of the delivery catheter to allow the tether head to engage with and / or disengage from the IMD within the receptacle volume.

[0006] A tether electrode supported by at least one of tether head and / or the conductive tether is configured to receive an intrinsic electrical signal produced by the heart of the patient. For example, the tether electrode may be at least a portion of an outer surface area of the tether head and / or conductive tether. The tether electrode is configured to receive the intrinsic electrical signal when the tether head and the IMD are within the receptacle volume of the device receptacle. Hence, the tether electrode may receive the signal when a wall of the device receptacle defining the receptacle volume acts to at least partially shield one or more device electrodes of the IMD from sufficiently receiving the intrinsic electrical signal. In some examples, the tether electrode may be in contact with a conductive portion of the IMD, e.g., of a housing of the IMD, and may receive the intrinsic signals via the conductive portion of the IMD.

[0007] The device tether, e.g., the tether head and the tether, is configured to conduct the intrinsic electrical signal from the tether electrode to processing circuitry extracorporeal to the patient. Thus, the device tether may enable receiving and processing the signal when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state. For example, when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state, the device tether may allow a medical system and / or a clinician to assess whether the device receptacle holding the IMD is within an atrium of a heart, a ventricle of the heart, a coronary sinus of the heart, or some other portion of the heart. In some examples, the device tether may allow assessment of a position and / or orientation of the receptacle and / or the IMD relative to target tissue of the heart.

[0008] In an example, a medical system comprises: a device tether comprising: a tether electrode configured to receive an intrinsic electrical signal produced by a heart of a patient, a tether head configured to engage an implantable medical device within aAtty Ref. No: A0011305WO01 chamber of the heart, a conductive tether including a tether distal portion configured to be intracorporeal to a patient and a tether proximal portion configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal, wherein the tether head is attached to the tether distal portion, wherein at least one of the tether head or the tether distal portion supports the tether electrode, wherein the tether electrode is configured to conduct the intrinsic electrical signal to the tether distal portion, wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion; and processing circuitry configured to receive the intrinsic electrical signal using a first electrode configured to electrically connect to the tether proximal portion and a second electrode configured to electrically connect to a portion of the patient.

[0009] In an example, a medical system comprises: a device tether comprising: a tether electrode configured to receive an intrinsic electrical signal produced by a heart of a patient, a tether head configured to engage an implantable medical device within a chamber of the heart, a conductive tether including a tether distal portion configured to be intracorporeal to a patient and a tether proximal portion configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal, wherein the tether head is attached to the tether distal portion, wherein at least one of the tether head or the tether distal portion supports the tether electrode, wherein the tether electrode is configured to conduct the intrinsic electrical signal to the tether distal portion, and wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion, and a handle supported by the tether proximal portion, the handle configured to cause the tether head to disengage from the implantable medical device in the chamber of the heart; a first electrode is configured to electrically connect to the tether proximal portion, wherein the first electrode is configured to receive the intrinsic electrical signal from the tether proximal portion; a second electrode configured to electrically connect to skin of the patient; processing circuitry configured to receive the intrinsic electrical signal using the first electrode and the second electrode; and a display device in communication with the processing circuitry, wherein the display device is configured to provide a visual indication of the intrinsic electrical signal using the communication.

[0010] In an example, a method comprises: receiving, using a tether electrode of aAtty Ref. No: A0011305WO01 device tether including a tether head and a conductive tether located within a chamber of a heart of a patient, an intrinsic electrical signal produced by the heart, wherein the tether head is configured to engage an implantable medical device within the chamber of a heart, wherein the tether electrode is electrically connected to a tether distal portion of the conductive tether, wherein the tether distal portion is electrically connected to a tether proximal portion of the conductive tether, wherein the tether proximal portion is extracorporeal to the patient; and receiving, using processing circuitry, the intrinsic electrical signal using a first electrode electrically connected to the tether proximal portion and a second electrode electrically connected to a portion of the patient.

[0011] In an example, a method comprises: positioning, using a device receptacle supported by a delivery catheter, an implantable medical device within a chamber of a heart of a patient, wherein the device receptacle defines a receptacle volume holding the implantable medical device and defines a receptacle opening configured to allow the implantable medical device to pass therethrough; supporting, using a tether distal portion of a conductive tether extending through a catheter lumen defined by the delivery catheter, a tether head within the receptacle volume, wherein the implantable medical device is between the tether head and the receptacle opening; receiving, using a tether electrode supported by at least one of the tether head or the tether distal portion, an intrinsic electrical signal produced by the heart; conducting, using the tether electrode, the intrinsic electrical signal to the tether distal portion; conducting, using the tether distal portion, the intrinsic electrical signal to a tether proximal portion of the conductive tether, wherein the tether proximal portion is extracorporeal to the patient; receiving, using processing circuitry supported by an external device extracorporeal to the patient, the intrinsic electrical signal using a first electrode electrically connected to the tether proximal portion and a second electrode electrically connected to a portion of the patient; and providing, using a display device in communication with the processing circuitry, a visual indication of the intrinsic electrical signal.

[0012] The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.Atty Ref. No: A0011305WO01 BRIEF DESCRIPTION OF DRAWINGS

[0013] FIG.1 is a conceptual diagram illustrating an example medical system and device receptacle within a heart.

[0014] FIG.2 is a perspective illustration of an example delivery catheter and device tether.

[0015] FIG.3 is a schematic diagram of a device tether, a first electrode, a second electrode, and processing circuitry.

[0016] FIG.4 is a plan view of an example tether head.

[0017] FIG.5 illustrates an example technique for receiving a signal using a tether electrode.

[0018] FIG.6 illustrates an example technique for receiving a signal using a tether electrode and processing circuitry.

[0019] FIG.7A is a cross-sectional schematic diagram of an example tether head, with the cutting plane taken through a device axis and parallel to the page.

[0020] FIG.7B is a cross-sectional schematic diagram of the tether head of FIG.7A in a disengagement configuration, with the cutting plane taken through the device axis and parallel to the page.

[0021] FIG.7C is a cross-sectional schematic diagram of the tether head of FIG.7A and FIG.7B in an engagement configuration, with the cutting plane taken through the device axis and parallel to the page.

[0022] FIG.8 is a schematic block diagram of an implantable medical device. DETAILED DESCRIPTION

[0023] This disclosure describes a medical system configured to deliver, position, and / or retrieve an implantable medical device (“IMD”) within an anatomical volume (e.g., a chamber of a heart) within a patient. In examples, the medical system is configured to deliver the IMD to a target site in the patient and convey signals (e.g., using processing circuitry) indicative of the positioning and / or proximity of the IMD relative to the target site, indicative of the suitability of the target site, indicative of the deployment of the IMD, and / or for other reasons.

[0024] The medical system includes a device tether including a conductive tether supporting a tether head configured to engage with and / or disengage from the IMD. TheAtty Ref. No: A0011305WO01 medical system may further include a delivery catheter supporting a device receptacle configured to hold the IMD within a receptacle volume of the device receptacle. The device receptacle defines a receptacle opening which opens to the receptacle volume and which is configured to allow the IMD to pass therethrough. In examples, a wall of the device receptacle defines a boundary of the receptacle volume. The conductive tether extends through a lumen of the delivery catheter to allow the tether head to engage with and / or disengage from the IMD within the receptacle volume.

[0025] A tether electrode supported by at least one of tether head and / or the conductive tether is configured to receive an intrinsic electrical signal produced by the heart of the patient. For example, the tether electrode may be at least a portion of an outer surface area of the tether head and / or conductive tether. The tether electrode is configured to receive the intrinsic electrical signal when the tether head and the IMD are within the receptacle volume of the device receptacle. Hence, the tether electrode may receive the signal when a wall of the device receptacle defining the receptacle volume acts to at least partially shield one or more device electrodes of the IMD from sufficiently receiving the intrinsic electrical signal. The device tether is configured to conduct the intrinsic electrical signal from the tether electrode to processing circuitry extracorporeal to the patient using the conductive tether. Thus, the device tether may enable receiving and processing the signal when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state. For example, when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state, the medical system may utilize the device tether to assess and / or allow a clinician to assess whether the device receptacle holding the IMD is within an atrium of the heart, a ventricle of the heart, a coronary sinus of the heart, or some other portion of the heart 101.

[0026] The conductive tether includes a tether distal portion configured to be intracorporeal to the patient and a tether proximal portion configured to be extracorporeal to the patient (e.g., as the conductive tether extends through the lumen of the delivery catheter). The tether distal portion supports the tether head. The device tether is configured to conduct an intrinsic electrical signal received by the tether electrode to the tether distal portion. The conductive tether is configured to conduct the intrinsic electrical signal from the tether distal portion to the tether proximal portion.

[0027] The medical system includes processing circuitry configured to receive theAtty Ref. No: A0011305WO01 intrinsic electrical signal sensed by the tether electrode. The processing circuitry may be extracorporeal to the patient. For example, processing circuitry may be mechanically supported by an external device configured to be extracorporeal to the patient when the tether head, the tether distal portion, the device receptacle, and / or the IMD 102 intracorporeal to the patient. Use of processing circuitry extracorporeal to the patient instead of or in addition to IMD processing circuitry carried by the IMD may improve a reception of and / or a processing of the intrinsic electrical signal when the IMD is positioned within the receptacle volume of the device receptacle.

[0028] Processing circuitry is configured to receive the intrinsic electrical signal using a first electrode and a second electrode. The first electrode is configured to electrically connect to the tether proximal portion. The second electrode is configured to electrically connect to a portion of a patient, such as skin of the patient. In examples, the first electrode is configured to electrically connect with and / or electrically isolate from the tether proximal portion. For example, first electrode may comprise a clip, a mechanically mating plug and socket, a switch, a breaker, or some other device configured to electrically connect with the tether proximal portion. In some examples, the second electrode is a cutaneous electrode affixed to the skin of the patient. The first electrode and the second electrode are configured to be extracorporeal to the patient and / or otherwise displaced from device receptacle and / or the IMD.

[0029] In examples, the processing circuitry of the external device is configured to have a higher gain as compared to the IMD processing circuitry. For example, the processing circuitry may be configured to increase a power and / or amplitude of the intrinsic electrical signal received using the first electrode and / or the second electrode as compared to when IMD processing circuitry receives the intrinsic electrical signal using one or more device electrodes supported by the IMD. The higher gain may result in improved resolution and / or fidelity of a waveform indicative of the intrinsic electrical signal received when, for example, the IMD is within the receptacle volume of the device receptacle and device electrodes of the IMD are substantially shielded by the device receptacle, and / or when the IMD is substantially in a de-energized state (e.g., prior to energizing the IMD in preparation for implantation). The improved resolution and / or fidelity may improve informational content and / or usefulness to a clinician observing and / or other circuitry receiving the waveform. For example, reception of the intrinsicAtty Ref. No: A0011305WO01 electrical signal using the device tether may improve an ability to determine a location of the device receptacle and / or the IMD during a delivery of the IMD to a chamber of the heart (e.g., when the IMD may be substantially within the receptacle volume and / or substantially de-energized).

[0030] In examples, the medical system may be utilized to position the IMD within a chamber of the heart using device receptacle and the delivery catheter. The tether head may engage the IMD within the receptacle volume of the device receptacle. The tether distal portion of the conductive tether supports the tether head and extends through the delivery lumen defined by the delivery catheter.

[0031] The tether electrode may be used to receive the intrinsic electrical signal produced by the heart when the IMD is within the receptacle volume of the device receptacle. In examples, the tether electrode receives the intrinsic electrical signal when the IMD is positioned substantially between a receptacle opening to the receptacle volume and the tether head. The tether electrode may conduct the intrinsic electrical signal to the tether distal portion when the device receptacle, the IMD, the tether electrode, and the tether distal portion are intracorporeal to the patient. The tether distal portion may conduct the intrinsic electrical signal to the tether proximal portion, when the tether proximal portion is extracorporeal to the patient.

[0032] The processing circuitry supported by the external device may receive the intrinsic electrical signal using the first electrode electrically connected to tether proximal portion and the second electrode electrically connected to a portion of the patient. In examples, a display of a display device provides a visual indication of the intrinsic electrical signal. A clinician may utilize the visual indication to assess a location of the device receptacle and / or the IMD during delivery of the IMD to the chamber of the heart (e.g., when the IMD may be substantially within the receptacle volume and / or substantially de-energized).

[0033] Hence, the medical system is configured to detect an intrinsic electrical signal of a heart using a tether electrode supported by at least one of tether head and / or the conductive tether. The tether electrode is configured to receive the intrinsic electrical signal when the tether head and the IMD are within the receptacle volume of the device receptacle. The tether electrode may receive the signal when a wall of the device receptacle defining the receptacle volume acts to at least partially shield one or moreAtty Ref. No: A0011305WO01 device electrodes of the IMD from sufficiently receiving the intrinsic electrical signal. Thus, the device tether may enable receiving and processing the signal when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state. For example, when the device electrodes are substantially shielded and / or the IMD is in a substantially de-energized state, the medical system may utilize the device tether to assess and / or allow a clinician to assess whether the device receptacle holding the IMD is within an atrium of the heart, a ventricle of the heart, a coronary sinus of the heart, or some other portion of the heart 101.

[0034] FIG.1 is a conceptual diagram illustrating an example medical system 100 within a right atrium (“RA”) of a heart 101. Medical system 100 is configured to deliver and / or retrieve an implantable medical device 102 (“IMD 102”) to and / or from the vicinity of a target site 104 of heart 101. Although described herein in the context of delivering IMD 102 into the vasculature, e.g., heart 101, the devices, systems, and techniques of this disclosure may be used to deliver an IMD or other medical device to any anatomical location.

[0035] Medical system 100 includes a delivery catheter 106 supporting a device receptacle 108. Device receptacle 108 is configured to hold IMD 102 during delivery, deployment, and / or retrieval of IMD 102. Device receptacle 108 includes a receptacle wall 110 defining a receptacle volume 112 configured to hold and / or support IMD 102 during the delivery, deployment, and / or retrieval of IMD 102. In examples, device receptacle 108 defines a distal opening 109 (“receptacle opening 109”) which opens into receptacle volume 112. Receptacle opening 109 may be configured to allow at least IMD 102 to pass therethrough. In examples, medical system 100 is configured to deploy IMD 102 from device receptacle 108 (e.g., from a position within receptacle volume 112) and through receptacle opening 109 to cause IMD 102 to engage tissues within target site 104. In examples, medical system 100 is configured to cause IMD 102 to disengage from tissues within target site 104 to, for example, retrieve IMD 102 from and / or reposition IMD 102 within heart 101.

[0036] Delivery catheter 106 is configured to deliver device receptacle 108 and / or IMD 102 to an anatomical volume of the patient (e.g., the RA). Optionally, such delivery can be performed with IMD 102 “preloaded” or present within device receptacle 108 during advancement of delivery catheter 106 to the anatomical volume, or IMD 102 can beAtty Ref. No: A0011305WO01 advanced to device receptacle 108 after delivery catheter 106 including device receptacle 108 has been advanced to the anatomical volume. Optionally, delivery catheter 106 may be advanced to the anatomical volume of the patient through a surrounding tubular member (not shown), such as a sheath or guide catheter, which may be placed with its distal end in the anatomical volume before delivery catheter 106 is advanced through the surrounding tubular member. In examples, delivery catheter 106 is configured to retrieve device receptacle 108 and / or IMD 102 from the anatomical volume of the patient. Delivery catheter 106 may include a distal portion 114 (“delivery catheter distal portion 114”) configured to be intracorporeal to the patient and a proximal portion 116 (“delivery catheter proximal portion 116”) which may be extracorporeal to the patient when delivery catheter distal portion 114 is intracorporeal. Delivery catheter distal portion 114 may support (e.g., be attached to and / or be a substantially unitary component with) device receptacle 108. In examples, delivery catheter 106 is configured to deliver and / or retrieve device receptacle 108 and / or IMD 102 using vasculature of a patient, such as an inferior vena cava (IVC), superior vena cava (SVC) or other vasculature leading to the anatomical volume. Delivery catheter 106 may define a lumen 118 (“delivery lumen 118”) which opens to receptacle volume 112.

[0037] In examples, medical system 100 includes a device tether 120 configured to engage IMD 102 when, for example, IMD 102 is positioned within receptacle volume 112. Device tether 120 can be used to, e.g., advance IMD 102 distally from device receptacle 108, through receptacle opening 109, to deploy IMD 102 into the anatomical volume. Device tether 120 can also be used to, e.g., extract and / or retract IMD 102 from the anatomical volume, through receptacle opening 109, into device receptacle 108. Device tether 120 includes an electrically conductive tether 121 including a tether body 122. Tether body 122 includes a distal portion 124 (“tether distal portion 124”) configured to be intracorporeal to the patient and a proximal portion 126 (“tether proximal portion 126”) which may be extracorporeal to the patient when tether distal portion 124 is intracorporeal. Device tether 120 and / or component(s) thereof, such as tether 121 and tether body 122, can comprise any suitable catheter or elongate member, or inner member (e.g., relative to delivery catheter 106). Device tether 120, tether 121 and / or tether body 122 can possess sufficient column strength or ”pushability” to advance IMD 102 distally from device receptacle 108, e.g., in the process of deployment, and / or, in some embodiments, toAtty Ref. No: A0011305WO01 advance IMD 102, or device tether 120 itself without IMD 102 attached thereto, along the length of delivery catheter 106 including proximal portion 116 and distal portion 114 thereof. Device tether 120, tether 121 and / or tether body 122 may possess sufficient tensile strength to extract and / or retract IMD 102 from the anatomical volume, through receptacle opening 109, into device receptacle 108, and / or, in some embodiments, through the length of delivery catheter 106 including proximal portion 116 and distal portion 114 thereof. Device tether 120, tether 121 and / or tether body 122 may possess sufficient torque transmission capability to screw and / or unscrew IMD 102 into target tissue in the anatomical volume. Where IMD 102 is attached to target tissue without need for screwing or rotating (e.g. where IMD 102 is fixated via one or more tines), or where other component(s) perform the screwing / unscrewing function, device tether 120, tether 121 and / or tether body 122 need not possess this capability.

[0038] Tether distal portion 124 supports and / or is attached to a tether head, such as tether head 128, configured to engage IMD 102. At least tether body 122 may be configured to translate (e.g., slidably translate) and / or rotate within delivery lumen 118 (e.g., translate and / or rotate relative to delivery catheter 106). Device tether 120 may be configured such that the translation and / or rotation of tether body 122 causes tether body 122 and / or tether head 128 to impart translational and / or rotational forces on IMD 102, such that IMD 102 translates and / or rotates relative to receptacle wall 110. For example, device tether 120 may be configured to translate within delivery lumen 118 to impart (e.g., via tether head 128) a translational force on IMD 102 causing IMD 102 to translate (e.g., within receptacle volume 112) in the proximal direction P or the distal direction D relative to receptacle wall 110. Device tether 120 may be configured to rotate within delivery lumen 118 to impart (e.g., via tether head 128) a rotational force on IMD 102 causing IMD 102 to rotate (e.g., within receptacle volume 112) about a device axis LD defined by IMD 102. In some examples, tether head 128 and tether body 122 may be substantially separate components. In some examples, tether head 128 may be substantially contiguous with tether body 122, such that tether head 128 and tether body 122 define a unified component. In FIG.1, portions of tether body 122, tether head 128, and IMD 102 positioned within delivery lumen 118 and / or receptacle volume 112 are depicted with dashed lines.Atty Ref. No: A0011305WO01

[0039] Although IMD 102 is depicted in FIG.1 as partially within receptacle volume 112, in some examples, IMD 102 and / or device receptacle 108 may be configured such that IMD 102 may position wholly within receptacle volume 112. For example, IMD 102 and / or device receptacle 108 may be configured such that one or more of a distal end 113 defined by a housing of IMD 102 (“IMD distal end 113”), a first distal electrode 103, a second distal electrode 105 (e.g., an atrial electrode), and / or an attachment member 132 may be proximal to receptacle opening 109, distal to receptacle opening 109, and / or substantially even with receptacle opening 109. Device tether 120 is configured to cause IMD 102 to translate in the proximal direction P or the distal direction D within receptacle volume 112 to position IMD distal end 113, second distal electrode 105, first distal electrode 103, and / or attachment member 132 proximal to receptacle opening 109, distal to receptacle opening 109, and / or substantially even with receptacle opening 109.

[0040] At least one of tether head 128 or tether distal portion 124 supports an electrode 129 (“tether electrode 129”). Tether head 128 or tether distal portion 124 may support tether electrode 129 such that tether electrode 129 remains substantially stationary with respect to at least some portion of tether head 128 or tether distal portion 124 when tether head 128 or tether distal portion 124 moves in the distal direction D, moves in the proximal direction P, and / or rotates about an axis defined by device tether 120. For example, tether electrode 129 may be configured to position at least within delivery lumen 112, within receptacle volume 112, or distal to receptacle opening 109 respectively when tether head 128 or tether distal portion 124 is positioned (e.g., using tether body 122) within delivery lumen 112, within receptacle volume 112, or distal to receptacle opening 109 respectively.

[0041] In some examples, tether electrode 129 comprises at least a portion of a body comprising tether head 128 and / or tether distal portion 124 (“device tether body”). For example, tether electrode 129 may comprise at least a portion of a body of tether head 128 (e.g., tether head body 177 (FIG.4)) and / or at least a portion of an outer surface of tether head 128 (e.g., head outer surface 179 (FIG.4)). In some examples, tether electrode 129 comprises (e.g., is defined by) a surface of the device tether body. For example, the device tether body may be a conductive material configured to be covered by an insulative material. Tether electrode 129 may be some portion of a surface defined by the device tether body where the insulative cover is substantially removed. In some examples, theAtty Ref. No: A0011305WO01 device tether body may be substantially entirely uncovered by any insulative material, such that tether electrode 129 comprises substantially the entirety of the tether head body. In some examples, tether electrode129 may be a substantially separate component affixed to, attached to, and / or otherwise supported by the device tether body.

[0042] As an alternative to the configuration shown in FIG.4 and described herein, the tether head or tether head may comprise any suitable mating interface or abutment coupled to, or formed on or in, tether 121 or tether distal portion 124 and configured to mate with, receive and / or abut a proximal portion of IMD 102. The tether head or tether head may, but need not, possess the ability to transmit torque to IMD 102 for the purpose of screwing or unscrewing it to or from target tissue; this may depend on whether IMD 102 is fixated via a helix, or tines, a combination thereof, or through some other fixation component(s). The tether head or tether head may be further implemented via one or more releasable, removable, retractable or severable string(s), filament(s), thread(s), etc., or one or more snare(s), e.g., along with a mating interface or abutment as described herein, to provide a releasable attachment of IMD 102 to device tether 120. Such string(s), filament(s), thread(s), snare(s), etc. can grip, loop through, anchor within, or otherwise interact with a proximal portion of IMD 102 to facilitate such releasable attachment. In any of these configurations, tether electrode 129 may be supported by or formed on or in any portion of the tether head, tether head, or tether distal portion 124.

[0043] Medical system 100 is configured to position IMD 102 in proximity to target site 104 such that IMD 102 may be anchored to tissues within target site 104. In examples, IMD 102 includes an attachment member 132 configured to engage tissues within target site 104. For example, delivery catheter 106 may be configured to (e.g., under the influence of a clinician) traverse vasculature of the patient to position device receptacle 108 and IMD 102 in proximity to target site 104. Medical system 100 (e.g., tether body 122 and / or tether head 128) is configured to (e.g., when attachment member 132 is a helical member) impart a torque to IMD 102 to cause attachment member 132 to engage tissues (e.g., tissue within target site 104) when attachment member 132 is within or in proximity to target site 104. In examples, medical system 100 (e.g., tether body 122 and / or tether head 128) is configured to impart a force in the distal direction D to IMD 102 to cause attachment member 132 to engage tissues and / or impart a force in the proximal direction P to IMD 102 to cause attachment member 132 to disengage from tissues (e.g.,Atty Ref. No: A0011305WO01 when attachment member 132 includes one or more tines). Medical system 100 is configured such that tether body 122 and / or tether head 128 may be disengaged from IMD 102 as IMD 102 remains anchored to tissues within or in proximity to target site 104. Delivery catheter 106, device receptacle 108, and device tether 120 may subsequently be withdrawn from the patient (e.g., via vasculature of the patient).

[0044] In examples, IMD 102 includes processing circuitry 133 (“IMD processing circuitry 133”). Medical system 100 may be configured to use IMD processing circuitry 133 to sense an intrinsic electrical signal generated by heart 101 to, for example, assess electrical activity in proximity of IMD 102 (e.g., in proximity to attachment member 132), conduct pace mapping to determine a suitable placement of IMD 102, evaluate a suitability of pacing delivered by IMD 102 at a particular location, evaluate a position of IMD 102 during an implantation, evaluate a placement of a device electrode relative to a vessel wall, and / or for other reasons. In examples, IMD processing circuitry 133 is mechanically supported by a housing of IMD 102, such that IMD processing circuitry 133 is intracorporeal to the patient when, for example, tether distal portion 124, tether head 128, device receptacle 108 and / or IMD 102 are intracorporeal to the patient.

[0045] In examples, IMD processing circuitry 133 is configured to sense the intrinsic electrical signal using electrodes supported by IMD 102 (e.g., a housing of IMD 102). For example, IMD processing circuitry 133 may be configured to sense the intrinsic electrical signal using two or more device electrodes 111 such as a first distal electrode 103 of IMD 102, a second distal electrode 105, a proximal electrode 107 (e.g., a return electrode), and / or other device electrodes of IMD 102. Device electrodes 111 may be configured to communicate with IMD processing circuitry 133. IMD processing circuitry 133 may be configured to process and / or condition a signal sensed by device electrodes 111 and / or other electrodes within medical system 100. In examples, one or more of device electrodes 111 (e.g., proximal electrode 107) may be configured to be positioned with receptacle volume 112 when IMD 102 resides at least partially within receptacle volume 112.

[0046] In some examples, for example when at least one of device electrodes 111 is positioned within receptacle volume 112, receptacle wall 110 and / or a body of IMD 102 may reduce reception of a signal (e.g., an intrinsic electrical signal) by the at least one of device electrodes 111. For example, when a given device electrode (e.g., proximalAtty Ref. No: A0011305WO01 electrode 107) is positioned within receptacle volume 112, receptacle wall 110 and / or the body of IMD 102 may act to at least partially shield the given device electrode from adequately receiving the signal, act to attenuate the signal, and / or act to otherwise interfere with the signal as the signal travels over a signal path to the given device electrode. In some cases, receptacle wall 110 and / or the body of IMD 102 may at least partially block a signal path from a fluid environment surrounding device receptacle 108 (e.g., blood of the patient) to the given device electrode, such that receptacle wall 110 and / or the body of IMD 102 act to at least partially reduce a signal strength of the signal arriving at the given device electrode. For example, when the given device electrode positioned within receptacle volume 112 is generally reliant on a signal path proceeding through receptacle opening 109 for receipt of a signal, portions of IMD 102 positioned substantially between receptacle opening 109 and the given device electrode may act to attenuate, at least partially shield, and / or otherwise interfere with the signal prior to reception by the given device electrode. The attenuation, shielding, and / or interference of the signal may reduce an ability of IMD processing circuitry 133 to process and / or condition the sensed signal, potentially impacting the usefulness of the sensed signal to a clinician.

[0047] Medical system 100 is configured to receive a sensed signal (e.g., the intrinsic electrical signal) using device tether 120 instead of or in addition to device electrodes 111 to, for example, enhance sensing and / or processing of an intrinsic electrical signal produced by heart 101. Medical system 100 may receive the sensed signal using device tether 120 when, for example, proximal electrode 107 and / or other of device electrodes 111 are substantially shielded by receptacle wall 110 and / or a portion of IMD 102. For example, medical system 100 may be configured to receive the intrinsic electrical signal using device tether 120 when IMD 102 is positioned such that one or more of device electrodes 111 (e.g., proximal electrode 107) is substantially within receptacle volume 112. In examples, medical system 100 is configured to receive the sensed signal using tether electrode 129. Conductive tether 121 (e.g., tether body 122) is configured to conduct the signal from tether electrode 129 to tether proximal portion 126, such that the signal may be processed by processing circuitry external to the patient.

[0048] Medical system 100 may be configured to receive the intrinsic electrical signal via tether electrode 129 when tether electrode 129 is positioned within receptacle volume 112 and / or delivery lumen 118. Medical system 100 may be configured to receive theAtty Ref. No: A0011305WO01 intrinsic electrical signal via tether electrode 129 when IMD 102 is positioned within receptacle volume 112 (e.g., when tether head 128 is engaged with IMD 102 within receptacle volume 112). Medical system 100 may be configured to receive the intrinsic electrical signal via tether electrode 129 when IMD 102 is within receptacle volume 112 and substantially between device tether 128 and receptacle opening 109. Thus, medical system 100 may receive the intrinsic electrical signal via tether electrode 129 rather than (or in addition to) receiving the intrinsic electrical signal via one or more of device electrodes 111. Hence, medical system 100 may receive the intrinsic signal via tether electrode 129 when IMD 102 is positioned (e.g., within receptacle volume 112) such that receptacle wall 110 and / or a portion of IMD 102 substantially shields one or more of device electrodes 111, such as proximal electrode 107.

[0049] Conductive tether 121 (e.g., tether body 122) is configured to conduct the intrinsic signal from tether electrode 129 tether distal portion 124. Tether distal portion 124 is configured to conduct the intrinsic electrical signal from tether distal portion 124 to tether proximal portion 126. In examples, tether electrode 129 is supported by and / or defined by a portion of tether head 128. In some examples, instead of or in addition to being supported by and / or defined by tether head 128, tether electrode 129 may be supported by and / or defined by a portion of conductive tether 121 (e.g., tether body 122). Conductive tether 121 may be configured to conduct the intrinsic electrical signal substantially from tether head 128 to tether proximal portion 126 (e.g., via tether distal portion 124).

[0050] Medical system 100 includes processing circuitry 134 configured to receive the intrinsic electrical signal sensed by tether electrode 129. Processing circuitry 134 is configured to be mechanically supported by an external device 136 and / or another device of medical system 100. External device 136 and / or processing circuitry 134 may be configured to be extracorporeal to the patient and / or otherwise displaced from device receptacle 108 and / or IMD 102 when, for example, tether distal portion 124, tether head 128, device receptacle 108 and / or IMD 102 are intracorporeal to the patient. Use of processing circuitry 134 (e.g., via device tether 120) instead of or in addition to IMD processing circuitry 133 when IMD 102 is at least partially positioned within receptacle volume 112 may improve a reception of and / or a processing of the intrinsic electrical signal.Atty Ref. No: A0011305WO01

[0051] Processing circuitry 134 may be configured to receive the sensed signal using a first electrode 138 and a second electrode 139. First electrode 138 is configured to electrically connect to tether proximal portion 126. In examples, first electrode 138 is configured to contact tether proximal portion 126 to establish the electrical connection with tether proximal portion 126. First electrode 138 may be configured to displace from tether proximal portion 126 to electrically isolate (e.g., break the electrical connection) from tether proximal portion 126. In examples, first electrode 138 is configured to be manipulated by a clinician to cause first electrode 138 to electrically connect with and / or electrically isolate from tether proximal portion 126. For example, first electrode 138 may comprise a clip, a mechanically mating plug and socket, a switch, a breaker, or some other device configured to contact tether proximal portion 126 and displace from tether proximal portion 126.

[0052] Second electrode 139 is configured to electrically connect to a portion of a patient, such as skin of the patient. In examples, second electrode 139 is an external electrode configured to be extracorporeal to the patient and / or otherwise displaced from device receptacle 108 and / or IMD 102. For example, in examples, second electrode 139 is a cutaneous electrode affixed to the skin of the patient. In examples, medical system 100 is configured to communicate (e.g., conduct) the signal from first electrode 138 and / or second electrode 139 using one or more conductive links, such as conductive link 135 between first electrode 138 and processing circuitry 134 and / or conductive link 137 between second electrode 139 and processing circuitry 134.

[0053] In some examples, processing circuitry 134 is configured to have a higher gain as compared to IMD processing circuitry 133. For example, processing circuitry 134 may be configured to increase a power and / or amplitude of the intrinsic electrical signal received via first electrode 138 and / or second electrode 139 as compared to when IMD processing circuitry 133 receives the intrinsic electrical signal using device electrodes 111. The higher gain may result in improved resolution and / or fidelity of a waveform indicative of the intrinsic electrical signal received such that, for example, the waveform may be more informational and / or useful to a clinician observing and / or other circuitry receiving the waveform. For example, when IMD 102 is positioned within device receptacle 108 such that one or more or device electrodes 111 (e.g., return electrode 107) is substantially shielded by receptacle wall 110, processing circuitry 134 may be configured to generate aAtty Ref. No: A0011305WO01 waveform indicative of the intrinsic electrical signal received via device tether 120 which has improved resolution and / or fidelity over that of a waveform generated by IMD 102 and indicative of the intrinsic electrical signal received by device electrodes 111. The improved resolution and / or fidelity may improve informational content and / or usefulness to a clinician observing and / or other circuitry receiving the waveform.

[0054] In some examples, device tether 120 (e.g., tether head 128 and / or tether body 122) is configured such that tether electrode 129 has a reduced impedance to reception of the intrinsic electrical signal as compared to one or more of device electrodes 111. For example, device tether 120 may be configured such that tether electrode 129 has a first impedance to the intrinsic electrical signal when tether electrode 129 is positioned within receptacle volume 112 and / or delivery lumen 118. IMD 102 may be configured such that one of device electrodes 111 (e.g., proximal electrode 107) has a second impedance to the intrinsic electrical signal when the one of device electrodes 111 is positioned within receptacle volume 112. The first impedance may be less than the second impedance. In examples, the first impedance is less than the second impedance when tether electrode 129 and the one of device electrodes 111 is in contact with a common conducting medium for the intrinsic electrical signal, such as blood of the patient. In some examples, tether electrode 129 defines a first contact area configured to contact and / or electrically communicate with the common conducting medium, and the one of device electrode 111 defines a second contact area configured to contact and / or electrically communicate with the common conducting medium, and the first contact area is greater than the second contact area.

[0055] Reception of the intrinsic electrical signal using device tether 120 may improve an ability to determine (e.g., using processing circuitry 134) a location of device receptacle 108 and / or IMD 102 during a delivery of IMD 102 to a chamber of heart 101. For example, during delivery of IMD 102 to heart 101 using device receptacle 108 (e.g., with IMD 102 positioned at least partially within receptacle volume 112), medical system 100 may be configured to utilize device tether 120 and processing circuitry 134 to assess and / or allow a clinician to assess whether device receptacle 108 is within an atrium of heart 101, a ventricle of heart 101, a coronary sinus of heart 101, or some other portion of heart 101. In some examples, processing circuitry 134 is configured to assess a location of device receptacle 108 and / or IMD 102 during a delivery of IMD 102 to a chamber of heartAtty Ref. No: A0011305WO01 101 using the intrinsic electrical signal obtained via device tether 120. In examples, use of device tether 120 allows reception of the intrinsic electrical signal when IMD 102 (and, e.g., IMD processing circuitry 133) is substantially deenergized (e.g., in an off state). Hence, use of device tether 120 may allow IMD 102 to remain in the off state until medical system 100 positions IMD 102 within the chamber of heart 101 and / or in proximity to target site 104.

[0056] In examples, medical system 100 includes a display device 141 including a display 151. Display device 141 may be configured to receive data from processing circuitry 134 and display information to a user (e.g., a clinician) using display 151. For example, display device 141 may be configured to display a waveform indicative of a sensed signal (e.g., an intrinsic electrical signal of heart 101) using display 151. In examples, the waveform is indicative of a sensed signal (e.g., the intrinsic electrical signal) received by processing circuitry 134 using device tether 120. Medical system 100 may be configured to communicate data indicative of the waveform and / or other information related to the waveform from processing circuitry 134 to display device 141 using one or more communication links such as communication link 157. In examples, display 151 is a liquid crystal display, an organic light emitting diode screen, a touchscreen, a cathode ray tube display, or other type of display configured to display information to a user. In some examples, medical system 100 is configured to communicate data indicative of a waveform indicative of a sensed signal (e.g., an intrinsic electrical signal) received by IMD processing circuitry 133 from IMD processing circuitry 133 to display device 141 using one or more communication links, such as communication link 161. In some examples, medical system 100 is configured to communicate data indicative of a waveform indicative of the sensed signal received by IMD processing circuitry 133 to a display device different from display device 141. In some examples, display device 141 and external device 136 may be portions of a single computing device (e.g., display device 141 and external device may be supported by a common housing of the single computing device).

[0057] In examples, medical system 100 is configured to use processing circuitry 134 when IMD 102 and / or IMD processing circuitry 133 are substantially in an off state (e.g., when IMD 102 and / or IMD processing circuitry 133 are substantially deenergized) and / or when one or more of device electrodes 111 are substantially within device receptacle 112.Atty Ref. No: A0011305WO01 For example, during delivery of IMD 102 to a chamber of the heart, medical system 100 may be configured to utilize tether electrode 129 to sense a signal using processing circuitry 134 (e.g., to determine a location of device receptacle 108 and IMD 102 during the IMD delivery). Medical system 100 may use processing circuitry 134 and tether electrode 129 to evaluate whether, for example, device receptacle 108 and IMD 102 are in an atrium or a ventricle of a patient. Medical system 100 may be configured to use IMD processing circuitry 133 when IMD 102 and IMD processing circuitry 133 are in a substantially on state (e.g., when IMD 102 and / or IMD processing circuitry 133 are at least partially energized) and one or more of device electrodes 111 may sufficiently receive the intrinsic electrical signal (e.g., when the one or more of device electrodes 111 are distal to receptacle opening 109). For example, during pace mapping and / or implantation of IMD 102 within a chamber of the heart, medical system 100 may be configured to utilize first distal electrode 103, second distal electrode 105, and / or proximal electrode 107 to sense a signal using IMD processing circuitry 133. The use of IMD processing circuitry 133 receiving signals substantially from electrodes of IMD 102 may provide more precise signals during, for example, pace mapping, implantation of IMD 102, or other actions.

[0058] In some examples, device tether 120 is configured to electrically communicate with some portion of IMD 102 (e.g., IMD retrieval structure 192, IMD housing 196, and / or proximal electrode 107 (FIG.3)) to assist IMD 102 in receiving a sensed signal for delivery to IMD processing circuitry 133. For example, IMD retrieval structure 192 may include one or more conductive portions configured to electrically contact tether electrode 129 when tether head 128 engages IMD 102. IMD retrieval structure 192 may be in electrical communication with proximal electrode 107 (e.g., via IMD housing 196). The electrical connection between tether electrode 129 and proximal electrode 107 or another conductive portion of IMD 102 may increase the effective area of tether electrode 129 to improve signal acquisition and quality. Additionally, medical system 100 may be configured to utilize the electrical connection between tether electrode 129 and proximal electrode 107 when medical system 100 uses processing circuitry 133 of IMD 102 to sense an intrinsic electrical signal of heart 101.

[0059] For example, when first distal electrode 103, second distal electrode 105, and / or another of device electrodes 111 are distal to receptacle opening 109 (e.g., outsideAtty Ref. No: A0011305WO01 of receptacle volume 112) and proximal electrode 107 is proximal to receptacle opening 109 (e.g., within receptacle volume 112), IMD processing circuitry 133 may utilize the electrical connection between tether electrode 129 and proximal electrode 107 to sense the intrinsic electrical signal. Medical system 100 may use IMD processing circuitry 133 to sense the intrinsic electrical signal between a first conductive path including first distal electrode 103, second distal electrode 105, and / or the other of device electrodes 111 distal to receptacle opening 109 and a second conductive path including proximal electrode 107 and tether electrode 129. The first conductive path may extend between, for example, first distal electrode 103, second distal electrode 105, and / or the other of device electrodes 111 distal to receptacle opening 109 and processing circuitry 133. The second conductive path may extend from, for example, processing circuitry 133, through proximal electrode 107 and tether electrode 129, through tether distal portion 124, through tether proximal portion 126, and to second electrode 139, e.g., via a clip or other connection between conductive path 137 and tether proximal portion 126. Hence, medical system 100 may be configured to use device tether 120 to enable IMD processing circuitry 133 to utilize a device electrode distal to receptacle opening 109 (e.g., first distal electrode 103) to sense the intrinsic electrical signal of heart 101 when proximal electrode 107 is proximal to receptacle opening 109 (e.g., within receptacle volume 112). For example, device tether 120 may enable IMD processing circuitry 133 to use first distal electrode 103 and / or second distal electrode 105 to conduct pace mapping and / or evaluate an implantation of IMD 102 prior to proximally withdrawing device receptacle 108 and device tether 120 away from IMD 102.

[0060] Although the examples herein discuss delivery, retrieval, and / or positioning of IMD 102 within the RA of heart 101, medical system 100 may be configured to deliver, retrieve, and / or position IMD 102 in any of the other chambers of heart 101 and / or in other anatomical volumes of a patient in a like manner as that described for the RA of heart 101. Further, although the examples herein discuss attachment member 132 defining a helix, attachment member 132 may defines other structures, such as one or more elongated tines extending from, for example, IMD distal portion 194. device tether 120 (e.g., conductive tether 121 and tether head 128) may be configured to exert a translational force (e.g., in the distal direction D) and / or a rotational torque on IMD 102 to cause attachment member 132 to engage tissues in proximity to target site 104. Target site 104 may include anAtty Ref. No: A0011305WO01 appendage of the RA, or the triangle of Koch region of the RA, or some other portion of heart 101, or some other location within a body of a patient.

[0061] FIG.2 is a plan drawing illustrating a portion of an example medical system 100 for delivering an IMD 102 within a receptacle volume 112 to a location within heart 101. FIG.3 is a schematic illustration of device receptacle 108 supported by delivery catheter distal portion 114 and device tether 120 extending through delivery lumen 118. In FIG.3, device receptacle 108 and delivery catheter 106 are shown as transparent for clarity.

[0062] Medical system 100 may include an introducer 140, delivery catheter 106, and device tether 120. In examples, introducer 140 is an elongate member defining an interior lumen. Introducer 140 is configured to be inserted (e.g., by a clinician), into vasculature of a patient to provide a channel, via the interior lumen, through which to insert a medical instrument, a device, or other therapy.

[0063] Delivery catheter 106 is configured to be inserted through the interior lumen of introducer 140 to deliver IMD 102 within the vasculature. Delivery catheter 106 includes delivery catheter distal portion 114 and delivery catheter proximal portion 116. Delivery catheter 106 may include a delivery catheter handle 142 and device receptacle 108. Delivery catheter handle 142 may be disposed substantially at a proximal end of delivery catheter proximal portion 116. In examples, delivery catheter handle 142 includes one or more elements (such as buttons, switches, etc.) configured to control a motion of (e.g., steer) a delivery catheter distal portion 114 and / or device receptacle 108.

[0064] Device receptacle 108 is supported by delivery catheter distal portion 114. In examples, device receptacle 108 is disposed substantially at a distal end 154 of delivery catheter distal portion 114 (“delivery catheter distal end 154”). Device receptacle 108 includes receptacle wall 110 defining receptacle volume 112. In examples, device receptacle 108 includes a hollow, substantially cylindrical body defining receptacle volume 112. Device receptacle 108 is configured to house and support IMD 102 (as depicted in FIG.3) within receptacle volume 112 as IMD 102 is being transported to and / or implanted within a vasculature of a patient. For example, a clinician may insert device receptacle 108 and delivery catheter distal portion 114 through the interior lumen of introducer 140 when introducer is disposed within a vasculature of a patient. Once device receptacle 108 has extended through introducer 140, the clinician may navigateAtty Ref. No: A0011305WO01 delivery catheter 106 (e.g., using delivery catheter handle 142) through the vasculature to an implant site (e.g., in proximity to target site 104 (FIG.1) within heart 101 of the patient. The clinician may cause IMD 102 to extend from and / or distal to receptacle opening 109 using device tether 120. The clinician may cause tether head 128 to disengage from IMD 102 (e.g., using handle 142) and proximally withdraw delivery catheter 106 and device tether 120 through introducer 140.

[0065] Device tether 120 (e.g., at least tether distal portion 124 and some portion of tether proximal portion 126) extends through delivery lumen 118 of delivery catheter 106. In examples, tether distal portion 124 is configured to extend through at least delivery catheter distal portion 114 and / or tether proximal portion 126 is configured to extend through at least delivery catheter proximal portion 116. A portion of tether distal portion 124 within delivery lumen 118 is shown with a dashed line in FIG.2. In examples, tether proximal portion 126 extends through delivery catheter handle 142.

[0066] Tether head 128 may be supported by tether distal portion 124. In examples, tether head 128 is disposed substantially at a distal end 125 of tether distal portion 124 (“tether distal end 125”) (FIG.3). Tether head 128 may be attached to and / or affixed to tether distal end 125. In some examples, a body of tether head is contiguous with and / or a substantially unitary body with tether distal portion 124, In some examples, tether head 128 and tether distal portion 124 define substantially separate bodies affixed to (e.g., attached to) each other (e.g. at tether distal end 125).

[0067] In examples, device tether 120 includes a tether handle 144. Tether handle 144 may be disposed substantially at a proximal end 127 of tether proximal portion 126 (“tether proximal end 127”). In examples, tether handle 144 includes one or more devices such as tether handle device 153 configured to cause tether head 128 to engage with and / or disengage from IMD 102. Tether handle device 153 may be one or more of a button, switch, and / or other devices configured to cause tether head 128 to engage with and / or disengage from IMD 102 (e.g., when manipulated by a clinician). Although FIG.2 and FIG.3 depict tether handle device 153 substantially on a side portion of a housing of tether handle 144, tether handle 144 may support tether handle device 153 and / or portions thereof at any location on the housing of tether handle 144. In some examples, tether handle 144 supports tether handle device 153 and / or portions thereof substantially in a distal proximal portion and / or proximal end of the housing tether handle 144. In examples,Atty Ref. No: A0011305WO01 device tether 120 includes a pull wire (e.g., wire 208 (FIG.7A–7C)) configured to enable tether head device 153 to cause tether head 128 to engage with and / or disengage from IMD 102.

[0068] A clinician may cause IMD 102 to extend from and / or distal to receptacle opening 109 using device tether 120. The clinician may cause tether head 128 to disengage from IMD 102 (e.g., using tether handle 144) and proximally withdraw delivery catheter 106 and device tether 120 through introducer 140. Conduction tether 121 may be of sufficient length that a clinician may manipulate tether handle 144 to advance tether head 128 distally through receptacle opening 109.

[0069] In some examples, with tether head 128 outside of receptacle volume 112 (e.g., distal to receptacle opening 109), a clinician may cause tether head 128 to engage IMD 102. The clinician may then use device tether 120 (e.g., tether handle 144 and / or conduction tether 121) to load IMD 102 within receptacle volume 112 via receptacle opening 109, and advance delivery catheter 106, with device tether 120 and IMD 102 therein, through introducer 140 and into the vasculature.

[0070] Referring mainly to FIG.3, delivery catheter 106 includes a body 148 (“delivery catheter body 148”) defining delivery lumen 118. Delivery lumen 118 extends from a distal lumen opening 150 defined by delivery catheter body 148 to a proximal lumen opening 152 defined by delivery catheter body 148. Distal lumen opening 150 opens into receptacle volume 112. In examples, delivery catheter body 148 defines distal lumen opening 150 substantially at a distal end 154 of delivery catheter body 148 (“delivery catheter distal end 154”). Delivery catheter body 148 may define proximal lumen opening 152 substantially at a proximal end 156 of delivery catheter body 148 (“delivery catheter proximal end 156”). Device tether 120 (e.g., tether body 122) is configured to translate (e.g., slidably translate) in the distal direction D and / or in the proximal direction P within delivery lumen 118. In examples, tether distal portion 124 and / or tether head 128 are configured to pass through distal lumen opening 150 as tether body 122 translates within delivery lumen 118. In examples, tether proximal portion 126 is configured to pass through proximal lumen opening 152 as tether body 122 translates within delivery lumen 118. In some examples, tether distal portion 124 and / or tether head 128 are configured to pass through proximal lumen opening 152 as tether body 122 translates within delivery lumen 118 (e.g., such that tether head 120 may be withdrawn inAtty Ref. No: A0011305WO01 its entirety from delivery lumen 118 via proximal lumen opening 152).

[0071] Delivery catheter body 148 may define and / or support a body 158 of delivery catheter handle 142 (“catheter handle body 158”). In some examples, catheter handle body 158 is a contiguous with and / or a substantially unitary body with delivery catheter body 148. In some examples, delivery catheter body 148 and catheter handle body 158 are substantially separate bodies affixed to (e.g., attached to) each other (e.g. at delivery catheter proximal end 156). In examples, catheter handle body defines a passage 160 (“catheter handle passage 160”) configured to open into delivery lumen 118 (e.g., through proximal lumen opening 152). Device tether 120 (e.g., tether body 122) may be configured to translate (e.g., slidably translate) in the distal direction D and / or in the proximal direction P within catheter handle passage 160 (e.g., as tether body 122 translates within delivery lumen 118). In some examples, tether distal portion 124 and / or tether head 128 are configured to pass through catheter handle passage 160 (e.g., such that tether head 120 may be withdrawn in its entirety from delivery lumen 118 via catheter handle passage 160).

[0072] Receptacle wall 110 of device receptacle 108 includes a wall body 162 defining an outer surface 164 (“wall outer surface 164”) on a first side of wall body 162 and an inner surface 166 (“wall inner surface 166”) on a second side of wall body 162 opposite the first side of wall body 162. Wall inner surface 166 may define a boundary of receptacle volume 112. Delivery catheter body 148 defines an outer surface 168 (“catheter outer surface 168”) on a first side of delivery catheter body 148 and an inner surface 170 (“catheter inner surface 170”) on a second side of delivery catheter body 148 opposite the first side of delivery catheter body 148. Catheter inner surface 170 may define a boundary of delivery lumen 118.

[0073] Wall outer surface 164 and at least some portion of catheter outer surface 168 are configured to be in fluidic communication with an external environment EO surrounding an exterior of device receptacle 108 and delivery catheter distal portion 114. For example, wall outer surface 164 and catheter outer surface 168 may be configured to be in fluid communication with a fluid environment within a chamber of heart 101 when device receptacle 108 and delivery catheter distal portion 114 are positioned (e.g., by a clinician) within heart 101. In examples, external environment EO comprises a fluid (e.g., blood of a patient).Atty Ref. No: A0011305WO01

[0074] Tether electrode 129 is configured to receive an intrinsic electrical signal of heart 101 (FIG.1) communicated by external environment EO. Tether electrode 129 may receive the intrinsic electrical signal communicated by external environment EO when tether electrode 129 is positioned within receptacle volume 112 and / or delivery lumen 118. Tether electrode 129 is configured to receive the intrinsic electrical signal via tether electrode 129 when IMD 102 is positioned within receptacle volume 112 (e.g., when tether head 128 is engaged with IMD 102 within receptacle volume 112). In examples, tether electrode 129 is configured to receive the intrinsic electrical signal when IMD 102 is within receptacle volume 112 and substantially between tether head 128 and receptacle opening 109. Thus, medical system 100 may receive the intrinsic electrical signal via tether electrode 129 when one or more of device electrodes 111 (e.g., proximal electrode 107) are substantially shielded from external environment EO by receptacle wall 110 and / or a portion of IMD 102. Medical system 100 may receive the intrinsic electrical signal via tether electrode 129 when IMD processing circuitry 133 is substantially de- energized.

[0075] Tether electrode 129 is configured to conduct the intrinsic electrical signal received to tether distal portion 124. Tether distal portion 124 is configured to conduct the intrinsic electrical signal from tether distal portion 124 to tether proximal portion 126. Processing circuitry 134 is configured to receive the intrinsic electrical signal using first electrode 138 electrically connected to tether proximal portion 126 and second electrode 139 electrically connected to a portion of the patient. In examples, tether proximal portion 126 extends through at least proximal lumen opening 152 when tether electrode 129 receives the intrinsic electrical signal. First electrode 138 may be electrically connected to a portion of tether proximal portion 126 which is proximal to proximal lumen opening 152. In some examples, tether proximal portion 126 extends through catheter handle passage 160 when tether electrode 129 receives the intrinsic electrical signal. First electrode 138 may be electrically connected to a portion of tether proximal portion 126 which is proximal to catheter handle passage 160. Hence, tether head 128 may be configured to receive the intrinsic electrical signal using tether electrode 129 with tether head 128 intracorporeal to the patient and conduct the signal using conductive tether 121 to first electrode 138 and processing circuitry 134 at a location extracorporeal to the patient. In examples, the intrinsic electrical signal is an electrogram (EGM) of heart 101.Atty Ref. No: A0011305WO01

[0076] First electrode 138 is configured to electrically connect to tether proximal portion 126 (e.g., as depicted in FIG.3). In examples, first electrode 138 is configured to electrically isolate from tether proximal portion 126 (e.g., as depicted in FIG.2). For example, first electrode 138 may include a conductor 172 (“first electrode conductor 172”) configured to contact tether proximal portion 126 to establish the electrical connection with tether proximal portion 126. First electrode conductor 172 may be configured to displace from tether proximal portion 126 to electrically isolate from tether proximal portion 126. In examples, first electrode 138 is configured to be manipulated (e.g., by a clinician) to cause first electrode conductor 172 to electrically connect with and / or electrically isolate from tether proximal portion 126. In examples, first electrode 138 includes a gripping portion 174 configured to be grasped and / or manipulated by a clinician. Gripping portion 174 may be configured such that a force exerted on gripping portion 174 (e.g., by the clinician) causes first electrode conductor 172 to electrically connect with and / or electrically isolate from tether proximal portion 126. In some examples, first electrode 138 is configured to establish a first position configured to cause contact between first electrode conductor 172 and tether proximal portion 126 and a second position configured to displace first electrode conductor 172 and tether proximal portion 126. In examples, first electrode 138 is biased (e.g., by a biasing element such as spring, a compressible material, or another biasing element) to transition from the second position to the first position. In examples, first electrode 138 is configured to transition from the first position to the second position when a force is exerted on gripping portion 174 (e.g., by a clinician).

[0077] In examples, tether body 122 of device tether 120 is an elongate body comprising a conductive material (e.g., an electrically conductive material), such as a metal, a conducting polymer, or other conducting material. Tether body 122 may be configured to conduct a sensed signal (e.g., the intrinsic electrical signal) from tether distal portion 124 to tether distal portion 126 using the conductive material. In examples, the conductive material extends from tether distal end 125 to tether proximal portion 126. In examples, the conductive material extends from tether proximal end 127 to tether distal portion 124. First electrode 138 (e.g., first electrode conductor 172) may be configured to electrically connect with the conductive material when first electrode 138 electrically connects to tether proximal portion 126.Atty Ref. No: A0011305WO01

[0078] In some examples, tether body 122 defines an outer surface 176 (“tether outer surface 176”). Tether outer surface 176 may be configured to substantially face catheter inner surface 170 when conductive tether 121 and / or tether body 122 extend through delivery lumen 118. In examples, tether outer surface 176 is a surface defined by the conductive material of tether body 122. First electrode 138 (e.g., first electrode conductor 172) may be configured to electrically connect with the conductive material via outer surface 176 when first electrode 138 electrically connects to tether proximal portion 126.

[0079] FIG.4 illustrates an example tether head 128. Tether head 128 is configured to engage with and / or disengage from IMD 102. Tether head 128 and the components discussed here are examples of a tether head which may be used by medical system 100. Medical system 100 may use other tether head assemblies having different components in other examples. As discussed, tether electrode 129 may be supported (e.g., mechanically supported) or defined by tether head 128 and / or tether body 122. For example, FIG.4 depicts tether electrode 129 (depicted with dashed lines) as extending over tether head 128 and tether body 122.

[0080] Tether head 128 includes a body 177 (“tether head body 177”) defining an outer surface 179 (“head outer surface 179”). In examples, head outer surface 179 is configured to be in fluidic communication with receptacle volume 112 when tether head 128 is positioned (e.g., at least partially positioned) within receptacle volume 112. In examples, tether electrode 129 comprises at least some portion of head outer surface 179 of tether head 128 and / or tether outer surface 176 of tether distal portion 124. Hence, device tether 120 may be configured to receive an intrinsic electrical signal (via tether electrode 129) using at least some portion of tether head 128 and / or at least some portion of tether distal portion 126.

[0081] Tether head 128 may be configured such that at least some portion of tether electrode 129 is in fluidic communication with receptacle volume 112 when tether head 128 is positioned within receptacle volume 112 (e.g., when engaging IMD 102) and / or is positioned within delivery lumen 118. For example, tether head 128 may be configured such that a portion of head outer surface 179 defining and / or supporting tether electrode 129 is in fluidic communication with receptacle volume 112 when tether head 128 is positioned within receptacle volume 112 and / or delivery lumen 118. Hence, tether electrode 129 may be configured to receive the intrinsic electrical signal via a fluid presentAtty Ref. No: A0011305WO01 within receptacle volume 112. For example, when blood of the patient and / or another fluid (e.g., saline, a medical dye, or another fluid) is present within receptacle volume 112, tether electrode 129 may be configured to receive the intrinsic electrical signal via the blood of the patient and / or the other fluid.

[0082] In some examples, tether electrode 129 is a portion of head outer surface 179 and / or tether outer surface 176. For example, head outer surface 179 and / or tether outer surface 176 may comprise conductive material configured to be covered by an insulative material. Tether electrode 129 may some portion of head outer surface 179 and / or tether outer surface 176 having the insulative cover removed. In some examples, head outer surface 179 and / or tether outer surface 176 may be substantially entirely uncovered by any insulative material, such that tether head 129 comprises substantially the entirety of head outer surface 179.

[0083] In examples, head body 177 is configured to couple to and / or coupled to tether distal portion 124 (e.g., tether body 122). In examples, tether electrode 129 is electrically connected to head body 177. In examples, head body 177 is configured to electrically connect with tether body 122. Hence, device tether 120 may be configured to conduct an intrinsic electrical signal from tether electrode 129 to tether distal portion 124 via an electrical path including head body 177 and tether body 122. In some examples, head outer surface 179 is configured to electrically connect with tether outer surface 176. Hence, device tether 120 may be configured to conduct an intrinsic electrical signal from tether electrode 129 to tether distal portion 124 via an electrical path including head outer surface 179 and tether outer surface 176. In examples, head body 177 and tether body 122 may be substantially separate components. In some examples, head body 177 may be substantially contiguous with tether body 122, head body 177 and tether body 122 define a unified component.

[0084] In examples, tether head 128 defines an aperture 184 to receive some portion of IMD 102 (e.g., some portion of IMD retrieval structure 192). Tether head 128 may be configured to define a passageway 185 leading to aperture 184, such that the portion of IMD 102 may be received within aperture 184 via passageway 185. Tether head 128 may be configured to vary a size of passageway 185 to engage with and / or disengage from IMD 102. For example, in an engagement configuration, tether head 128 may be configured to cause passageway 185 to be too narrow to permit the portion of IMD 102Atty Ref. No: A0011305WO01 (e.g., the portion of IMD retrieval structure 192) to pass through passageway 185, substantially preventing the portion of IMD 102 from exiting (and / or entering) aperture 184. In a disengagement configuration, tether head 128 may be configured to cause passageway 185 to be wider than in the engagement configuration, such that the portion of IMD 102 may pass through passageway 185 to exit (and / or enter) aperture 184. In examples, tether handle 144 (e.g., tether handle device 153) is configured to cause tether head 128 to transition between the engagement configuration and the disengagement configuration.

[0085] In examples, tether head 128 includes an engagement member 182 configured to increase and / or decrease a size of passageway 185 and / or aperture 184. Engagement member 182 may be configured to move relative to engagement section 180 to increase and / or decrease a size of passageway 185 and / or aperture 184. For example, engagement member 182 may be configured to move in the proximal direction P relative to engagement section 180 to increase a size of passageway 185 and / or aperture 184. Engagement member 182 may be configured to move in the distal direction D relative to engagement section 180 to decrease a size of passageway 185 and / or aperture 184. In examples, tether handle 144 (e.g., tether handle device 153) is configured to cause engagement member 182 to move relative to engagement section 180 to increase and / or decrease a size of passageway 185 and / or aperture 184.

[0086] Tether head 128 may be configured to exert a distally directed force, proximally directed force, or torque around a device axis LD (FIG.3) when IMD 102 (e.g., IMD retrieval structure 192) is trapped within aperture 184. Engagement member 182 may be configured to move relative to engagement section 180 (e.g., move in the proximal direction P) to increase a size of aperture 184, such that tether head 128 may disengage from retrieval structure 192 (e.g., IMD retrieval structure 192 may be released from aperture 184). For example, engagement member 182 may move relative to engagement section 180 such that proximal translation of tether head 128 relative to IMD 102 causes tether head 128 to disengage from IMD retrieval structure 192 (e.g., following implantation of IMD 102 in a patient using device tether 120).

[0087] In examples, tether head 128 includes a support section 178 coupled to an engagement section 180. Support section 178 may be coupled to tether distal portion 124. Engagement section 180 may define aperture 184. In examples, tether head body 177Atty Ref. No: A0011305WO01 includes at least one of a body of support section 178 (e.g., support section body 216 (FIGS.7A–7C)) and / or a body of engagement section 180 (e.g., engagement section body 202 (FIGS.7A–7C)). In examples, head outer surface 170 includes at least one of an outer surface 186 defined by engagement section 180 and / or an outer surface 188 defined by support section 178. In examples, tether head 128 is configured such that at least a portion of outer surface 186 (e.g., a portion defining and / or supporting tether electrode 129) is in fluidic communication with receptacle volume 112 when tether head 128 is positioned within receptacle volume 112 and / or delivery lumen 118. In examples, tether head 128 is configured such that at least a portion of outer surface 188 (e.g., a portion defining and / or supporting tether electrode 129) is in fluidic communication with receptacle volume 112 when tether head 128 is positioned within receptacle volume 112 and / or delivery lumen 118.

[0088] Returning primarily to FIG.3, device receptacle 108 (e.g., wall body 162) may define receptacle opening 109 substantially at a distal end 175 of device receptacle 108 (“receptacle distal end 175”). Receptacle opening 109 may be configured such that IMD 102 may egress from within receptacle volume 112 through receptacle opening 109 and / or ingress into receptacle volume 112 through receptacle opening 109. In examples, receptacle volume 112 is bounded at least partially by receptacle opening 109. Distal lumen opening 150 is configured to allow at least some portion of tether body 122 to position within receptacle volume 112 when another portion of tether body 122 is positioned within delivery lumen 118.

[0089] In examples, device receptacle 108 defines a receptacle axis LR extending at least through receptacle opening 109. In examples, wall inner surface 166 at least partially surrounds receptacle axis LR. In examples, receptacle axis LR extends through distal lumen opening 150. In some examples, receptacle volume 112 is bounded at least partially by distal lumen opening 150. In some examples, receptacle volume 112 defines a cross- sectional area perpendicular to receptacle axis LR, with the cross-sectional area defined by a curved, curvilinear, or polygonal boundary (e.g., a boundary defined by wall inner surface 166). In some examples, the cross-sectional area is defined by a substantially circular boundary. In examples, at least some portion of wall body 162 is between wall outer surface 164 and wall inner surface 166. In examples, wall outer surface 164 at least partially and / or substantially completely surrounds receptacle axis LR and / or wall innerAtty Ref. No: A0011305WO01 surface 166. Wall outer surface 164 may be configured such that wall outer surface 164 substantially faces in a direction away from receptacle axis LR, wall inner surface 166, and / or receptacle volume 112.

[0090] In some examples, medical system 100 (e.g., tether head 128) is configured to engage a proximal portion 190 of IMD 102 (“IMD proximal portion 190”). Tether head 122 may be configured to transfer a torque and / or a proximally directed or distally directed force to IMD 102. Tether body 122 may be configured to receive the torque and / or force (e.g., from a clinician) and transfer the torque and / or force to tether head 128. In examples, IMD proximal portion 190 includes a retrieval structure 192 (“IMD retrieval structure 192”). IMD retrieval structure 192 may be configured to engage with medical system 100 and / or another medical device to, for example, implant IMD 102 within an anatomical volume, retrieve IMD 102 from an anatomical volume, re-position IMD 102 within an anatomical volume, and / or re-orient IMD 102 within an anatomical volume. IMD 102 may include a distal portion 194 (“IMD distal portion 194”) opposite IMD proximal portion 190. In examples, IMD 102 (e.g., IMD distal portion 194) supports attachment member 132. In some examples, attachment member 132 is configured (e.g., as a helix) such that rotation of IMD 102 about a device axis LD defined by IMD 102 causes attachment member to engage and / or disengage tissues within target site 104.

[0091] IMD 102 may support (e.g., mechanically support) device electrodes 111. In examples, attachment member 132 supports first distal electrode 103. IMD distal portion 194 may support second distal electrode 105. IMD proximal portion 190 may support proximal electrode 107. In examples, IMD 102 includes a housing 196 (“IMD housing 196”) supporting one or more of device electrodes 111 (e.g., second distal electrode 105 and / or proximal electrode 107). In examples, at least one of device electrodes 111 (e.g., proximal electrode 107) is configured to be positioned with receptacle volume 112 when IMD 102 resides at least partially within receptacle volume 112. In examples, IMD 102 is configured such that at least one of device electrodes 111 (e.g., at least one of first distal electrode 103, second distal electrode 105, and / or proximal electrode 107) is in fluidic communication with receptacle volume 112 when IMD 102 resides at least partially within receptacle volume 112.

[0092] A technique 500 for receiving an intrinsic electrical signal produced by a heart is illustrated in FIG.5. Although technique 500 is described mainly with reference toAtty Ref. No: A0011305WO01 medical system 100 of FIGS.1–4 and FIGS.7A–8, technique 500 may be applied to other medical systems in other examples.

[0093] Technique 500 includes receiving, using a tether electrode 129 of a device tether 120, an intrinsic electrical signal of a heart 101 of a patient (502). At least one of a tether head 128 of device tether 120 or a conductive tether 121 of device tether 120 located within the chamber of heart 101 may support tether electrode 129. In examples, tether head 128 is engaged with an implantable medical device 102 within the chamber of heart 101. Conductive tether 121 includes tether distal portion 124 intracorporeal to the patient and tether proximal portion 126 extracorporeal to the patient. Tether electrode 129 is electrically connected to tether distal portion 124. Tether distal portion 124 is electrically connected to a tether proximal portion 126.

[0094] Technique 500 includes receiving, by at least one of processing circuitry 134 or IMD processing circuitry 133, the intrinsic electrical signal using a first electrode 138 electrically connected to tether proximal portion 126 and a second electrode 139 electrically connected to a portion of the patient (504). In examples, technique 500 includes conducting, using tether electrode 129, the intrinsic electrical signal to tether distal portion 124. In examples, technique 500 includes conducting, using tether distal portion 124, the intrinsic electrical signal to tether proximal portion 126. In examples, technique 500 includes providing, using a display device 141 in communication with the at least one of processing circuitry 134 or IMD processing circuitry 133, a visual indication of the intrinsic electrical signal. In examples, the intrinsic electrical signal is an intracardiac electrogram produced by heart 101. Processing circuitry 134 may be supported by an external device 136 extracorporeal to the patient. In examples, processing circuitry 133 is supported by an IMD 102.

[0095] Technique 500 may include receiving the intrinsic electrical signal using tether electrode 129 when IMD 102 is positioned at least partially within receptacle volume 112. In examples, technique 500 includes receiving the intrinsic electrical signal using tether electrode 129 when one or more of device electrodes 111 (e.g., distal electrode 107) is positioned at least partially within receptacle volume 112. Technique 500 may include receiving the signal using processing circuitry 134 when IMD 102 is positioned at least partially within receptacle volume 112. In examples, technique 500 includes receiving the signal using processing circuitry 134 when one or more of device electrodes 111 (e.g.,Atty Ref. No: A0011305WO01 distal electrode 107) is positioned at least partially within receptacle volume 112. Technique 500 may include receiving the intrinsic electrical signal using tether electrode 129 and / or receiving the intrinsic electrical signal by processing circuitry 134 when IMD 102 and / or processing circuitry 133 are substantially de-energized (e.g., substantially in an off state).

[0096] In examples, technique 500 includes assessing, using processing circuitry 134, a location of device receptacle 108 and / or IMD 102, such as a location within an atrium of heart 101, a ventricle of heart 101, a coronary sinus of heart 101, or some other portion of heart 101. In some examples, technique 500 includes assessing, using processing circuitry 134, the location of device receptacle 108 and / or IMD 102 using the intrinsic electrical signal sensed and / or received by tether electrode 129.

[0097] In some examples, technique 500 may include receiving the intrinsic electrical signal using processing circuitry 133 of IMD 102. Technique 500 may include, using tether head 128, establishing and / or maintaining an electrical connection between tether electrode 129 and proximal electrode 107 of IMD 102. In examples, proximal electrode 107 is within receptacle volume 112 when tether head 128 establishes and / or maintains the electrical connection between tether electrode 129 and proximal electrode 107. In some examples, one or more of first distal electrode 103, second distal electrode 105, and / or another of device electrodes 111 are distal to receptacle opening 109 (e.g., outside of receptacle volume 112) when tether head 128 establishes and / or maintains the electrical connection between tether electrode 129 and proximal electrode 107.

[0098] Processing circuitry 133 may receive the intrinsic electrical signal between a first conductive path including first distal electrode 103, second distal electrode 105, and / or the other of device electrodes 111 and a second conductive path including proximal electrode 107 and tether electrode 129. In examples, the first conductive path extends between first distal electrode 103, second distal electrode 105, and / or the other of device electrodes 111 and second electrode 139 or another electrode in electrical communication with the patient. In examples, the second conductive path extends through proximal electrode 107, tether electrode 129, tether distal portion 124, tether proximal portion 126, and first electrode 138 or another electrode in electrical communication with tether proximal portion 126. In examples, technique 500 includes pace mapping of heart 101 and / or evaluating an implantation of IMD 102 using processing circuitry 133.Atty Ref. No: A0011305WO01

[0099] In examples, technique 500 includes extending, using conductive tether 121, tether proximal portion 126 through a proximal lumen opening 152 of a delivery lumen 118 defined by a delivery catheter 106. Proximal lumen opening 152 may be extracorporeal to the patient. First electrode 138 may electrically connect to a portion of tether proximal portion 126 which is proximal to proximal lumen opening 152. In examples, a device receptacle 108 holding IMD 102 within a receptacle volume 112 positions IMD 102 within the chamber of heart 101. A distal lumen opening 150 of delivery lumen 118 may open into a receptacle volume 112 of device receptacle 108. Technique 500 may include extending, using conductive tether 121, at least one of tether head 128 or tether distal portion 124 through distal lumen opening 150 when tether proximal portion 126 extends through proximal lumen opening 152. Technique 500 may include positioning, using conductive tether 121, at least one of tether head 128 or tether distal portion 124 within receptacle volume 112 when tether proximal portion 126 extends through proximal lumen opening 152.

[0100] Technique 500 may include receiving, using tether electrode 129, the intrinsic electrical signal when tether head 128 is positioned in at least one of receptacle volume 112 or delivery lumen 118. At least some portion of tether head 128 may be in fluidic communication with receptacle volume 112 when tether electrode 129 receives the intrinsic electrical signal. In examples, tether electrode receives the signal via a fluid within receptacle volume 112. In examples, the technique includes filling, using at least receptacle opening 109, receptacle volume 112 with a fluid (e.g., blood of the patient). In some examples, tether electrode 129 receives the intrinsic electrical signal when IMD 102 is within receptacle volume 112 and between tether electrode 129 and receptacle opening 109.

[0101] In examples, technique 500 includes supporting tether electrode 129 using at least some portion of a head outer surface 179 defined by a tether head body 177 of tether head 128. Technique 500 may include positioning, using tether body 122, the portion of head outer surface 179 in fluidic communication with the fluid within receptacle volume 112 and / or delivery lumen 118.

[0102] In examples, technique 500 includes conducting the intrinsic electrical signal from tether electrode 129 to tether distal portion 124. Tether distal portion 124 may conduct the intrinsic electrical signal to tether proximal portion 126. Tether proximalAtty Ref. No: A0011305WO01 portion 126 may conduct the signal to first electrode 138. In examples, at least one of head outer surface 179 or tether head body 177 conducts the intrinsic electrical signal to at least one of tether outer surface 176 or tether body 122 when tether electrode 129 conducts the intrinsic electrical signal to tether distal portion 124. In examples, at least one of tether outer surface 176 or tether body 122 conducts the intrinsic electrical signal from tether distal portion 124 to tether proximal portion 126. In examples, at least one of tether outer surface 176 or tether body 122 conducts the intrinsic electrical signal from tether proximal portion 126 to first electrode 138.

[0103] Technique 500 may include contacting, using first electrode 138, a first electrode conductor 172 and the tether proximal portion 126 to electrically connect first electrode 138 and tether proximal portion 126. In examples, technique 500 includes displacing, using first electrode 138, first electrode conductor 172 from tether proximal portion 126 to electrically isolate first electrode 138 and tether proximal portion 126. In some examples, a biasing of first electrode 138 maintains the electrical contact between first electrode 138 and tether proximal portion 126. In some examples, technique 500 includes overcoming, using a gripping portion 174, the biasing of first electrode 138 to electrically isolate first electrode 138 and tether proximal portion 126.

[0104] A technique 600 for receiving an intrinsic electrical signal produced by a heart using processing circuitry extracorporeal to a patient is illustrated in FIG.6. Although technique 600 is described mainly with reference to medical system 100 of FIGS.1–4 and FIGS.7A–8, technique 600 may be applied to other medical systems in other examples. Further, technique 600 and any of the steps of technique 600 may be conducted in addition to or instead of technique 500 and any of the steps of technique 500. Likewise, technique 500 and any of the steps of technique 500 may be conducted in addition to or instead of technique 600 and any of the steps of technique 600.

[0105] Technique 600 includes positioning, using device receptacle 108 supported by delivery catheter 106, IMD 102 within a chamber of heart 101 of a patient (602). Device receptacle 108 holds IMD 102 within receptacle volume 112 between tether head 128 and receptacle opening 109 of device receptacle 108. Tether distal portion 124 of conductive tether 121 supports tether head 128 and extends through delivery lumen 118 defined by delivery catheter 106.Atty Ref. No: A0011305WO01

[0106] Technique 600 include receiving, using tether electrode 129 supported by at least one of tether head 128 or tether distal portion 124, an intrinsic electrical signal produced by heart 101 (604). Technique 600 includes conducting, using tether electrode 129, the intrinsic electrical signal to tether distal portion 124 (606). Technique 600 includes conducting, using tether distal portion 124, the intrinsic electrical signal to tether proximal portion 126, wherein tether proximal portion 126 is extracorporeal to the patient (608).

[0107] Technique 600 includes receiving, by processing circuitry 134 supported by external device 136 extracorporeal to the patient, the intrinsic electrical signal using first electrode 138 electrically connected to tether proximal portion 126 and second electrode 139 electrically connected to a portion of the patient (610). Technique 600 may include providing, using a display 151 of a display device 141, a visual indication of the intrinsic electrical signal.

[0108] In examples, technique 600 includes electrically connecting, using tether head 128, tether electrode 129 and an IMD housing 196 electrically connected to proximal electrode 107 of IMD 102. In examples, at least some portion of IMD housing 196 and the proximal electrode are positioned within the receptacle volume. Technique 600 may include conducting, using IMD housing 196, the intrinsic electrical signal from tether electrode 129 to proximal electrode 107. In examples, technique 600 includes receiving, by IMD processing circuitry 133 supported by IMD 102, proximal electrode 107, and at least one of a first distal electrode 103 and / or a second distal electrode 105, the intrinsic electrical signal. Technique 600 may include providing, using an indication device, a visual indication of the intrinsic electrical signal received by IMD processing circuitry 133, wherein the indication device is one display device 141 or another device.

[0109] In some examples, technique 600 includes receiving the intrinsic electrical signal using IMD processing circuitry 133 subsequent to receiving the intrinsic electrical signal using processing circuitry 134.

[0110] FIG.7A is a cross-sectional view of tether head 128 and IMD 102, with tether head 128 defining aperture 184 and passageway 185 into aperture 184. IMD 102 includes retrieval structure 192 including an attachment member 198. In FIG.7A, tether head 128 is in the engagement configuration, and attachment member 198 is displaced from aperture 184. FIG.7B is a cross-sectional view of tether head 128 and IMD 102, with tether headAtty Ref. No: A0011305WO01 128 in the disengagement configuration, and attachment member 198 is within aperture 184. FIG.7C is a cross-sectional view of tether head 128 and IMD 102, with tether head 128 in the engagement configuration, and attachment member 198 within aperture 184. In FIG.7A, 7B, and 7C, the cross-section is taken in a plane which includes a longitudinal axis LT of tether head 128.

[0111] Tether head 128 may be configured such that attachment member 198 may be received within aperture 184 via passageway 185. Tether head 128 may be configured to vary a size of passageway 185 to engage with and / or disengage from IMD 102. For example, in FIG.7A, with tether head 128 in the engagement configuration, tether head 128 is configured to cause passageway 185 to be too narrow to permit attachment member 198 to pass through passageway 185, substantially preventing attachment member 198 from entering aperture 184. In FIG.7B, with tether head 128 in the disengagement position, tether head 128 is configured to widen passageway 185, such that attachment member 198 may pass through passageway 185 into aperture 184. In FIG.7C, and with attachment member 198 within aperture 184, tether head has returned to the engagement configuration (e.g., narrowing passageway 185), such that attachment member 198 is substantially trapped within aperture 184. With tether head 128 in the engagement configuration and attachment member 198 within aperture 184 as illustrated in FIG.4D, tether head may return to the disengagement configuration of FIG.7B to permit attachment member 198 to exit aperture 184.

[0112] In examples, a body 202 of engagement section 180 (“engagement section body 202”) may at least partially define a boundary of aperture 184 and / or a boundary of passageway 185. In examples, passageway 185 extends from a distal end 204 of engagement section 180 (“engagement section distal end 204”) and opens into aperture 184. In examples, engagement section distal end 204 and / or passageway 185 is distal to aperture 184. A body 206 of engagement member 182 (“engagement member body 206”) may be configured to alter the width of passageway 185 (e.g., to cause the passageway to widen or narrow). For example, engagement member body 206 may be configured to move (e.g., in the proximal direction P and / or the distal direction D) relative to engagement section body 202 to alter the width of passageway 185. In examples, engagement member body 206 is configured to move in the proximal direction P relative to engagement section body 202 when tether head 128 transitions from the engagementAtty Ref. No: A0011305WO01 configuration to the disengagement configuration (e.g., when tether head 128 widens passageway 185). Engagement member body 206 may be configured to move in the distal direction D relative to engagement section body 202 when tether head 128 transitions from the disengagement configuration to the engagement configuration (e.g., when tether head 128 narrows passageway 185).

[0113] In examples, device tether 120 includes an elongate body or wire 208 (“wire 208”) configured to cause tether head 128 to transition between the engagement configuration and the disengagement configuration. In examples, wire 208 is configured to enable tether handle 144 (e.g., using tether handle device 153) to cause tether head 128 to transition between the engagement configuration and the disengagement configuration. In examples, tether head 128 is configured to transition between the engagement configuration and the disengagement configuration when wire 208 exerts a driving force F (FIG.7B) on tether head 128 (e.g., on engagement member body 206). In examples, tether head 128 includes an elastic member 210 configured to exert a member force FE (FIGS. 7A–7C) on a portion of tether head 128 (e.g., on engagement member body 206), and wire 208 is configured to overcome member force FE when wire 208 exerts driving force F. In examples, elastic member 210 is configured to cause tether head 128 to assume a first configuration (e.g., one of the engagement configuration or the disengagement configuration) when elastic member 210 exerts member force FE. Wire 208 may be configured to cause tether head 128 to assume a second configuration (e.g., the other of the engagement configuration or the disengagement configuration) when wire 208 exerts driving force F. In some examples, elastic member 210 is configured to cause tether head 128 to assume the engagement configuration when elastic member 210 exerts member force FE in the absence of wire 208 exerting driving force F, and wire 208 is configured to cause tether head 128 to assume the disengagement configuration when wire 208 exerts driving force F and overcomes member force FE.

[0114] In examples, elastic member 210 is configured to define an first length L1 when tether head 128 is in the first configuration, and define a second length L2 when tether head 128 is the second configuration. For example, as depicted in FIG.7A, elastic member 210 may define first length L1 when tether head is in the engagement configuration. As depicted in FIG.7B, elastic member 210 may define second length L2 when tether head 128 is in the disengagement configuration. In examples, first length L1Atty Ref. No: A0011305WO01 and second length L2 are substantially parallel to the distal direction D and / or the proximal direction P. In some examples, first length L1 and second length L2 define a shortest length between a distal end 212 of elastic member 210 (“elastic member distal end 212) and a proximal end 214 of elastic member 210 (“elastic member proximal end 214”) opposite elastic member distal end 212. In some examples, first length L1 and second length L2 define a length measured along elastic member 210 between elastic member distal end 212 and elastic member proximal end 214. In examples, elastic member 210 is configured such that member force FE increases as elastic member transitions from first length L1 to second length L2. In some examples, elastic member 210 may be configured such that member force FE increases as elastic member transitions from second length L2 to first length L1. In examples, a distal portion of wire 208 exerts driving force F on tether head 128. Wire 208 may include a proximal portion coupled to tether handle 144. Wire 208 may be configured such that increasing a tension of the proximal portion of wire 208 causes he distal portion of wire 208 to exert driving force F on tether head 128. In examples, tether handle 144 is configured to increase the tension of the proximal body of wire 208.

[0115] Tether handle 144 may be configured to cause wire 208 to exert driving force F on tether head and / or cause wire 208 to cease exerting driving force F on tether head 128 to control a configuration of tether head. Tether handle 144 may configured such that a clinician may cause tether handle 144 to exert and / or cease exerting driving force F on tether head 128. In some examples, tether handle 144 is configured to substantially lock into a configuration exerting driving force F and / or substantially lock into a configuration which ceases and / or fails to exert driving force F on tether head 128, such that tether head 128 substantially maintains one of the engagement configuration or the disengagement configuration until a locking member (e.g., of tether handle144) is operated (e.g., by a clinician). In examples, conductive tether 121 (e.g., tether body 122) defines a lumen 218 (“tether lumen 218”) in which a portion of wire 208 is received. In examples, tether lumen 218 extends substantially from tether distal end 125 to tether proximal end 127.

[0116] FIG.8 is a functional block diagram illustrating an example configuration of a device 218 configured to receive and / or detect an intrinsic electrical signal of heart 101 using device tether 120. Device 218 may be an example of external device 136 and / or IMD 102. Device 218 may include processing circuitry 220, sensing circuitry 222, therapyAtty Ref. No: A0011305WO01 delivery circuitry 224, sensors 226, communication circuitry 228, and memory 230. Processing circuitry 220 may be an example of processing circuitry 134 and / or processing circuitry 133. In some examples, memory 230 includes computer-readable instructions that, when executed by processing circuitry 220, cause device 218 and processing circuitry 220 to perform various functions attributed to device 218 and processing circuitry 220 herein. Memory 230 may include any volatile, non-volatile, magnetic, optical, or electrical media, such as a random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically-erasable programmable ROM (EEPROM), ferroelectric RAM (FRAM), flash memory, or any other digital media.

[0117] Processing circuitry 220 may include fixed function circuitry and / or programmable processing circuitry. Processing circuitry 220 may include any one or more of a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or equivalent discrete or analog logic circuitry. In some examples, processing circuitry 220 may include multiple components, such as any combination of one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, or one or more FPGAs, as well as other discrete or integrated logic circuitry.

[0118] Functions attributed to processing circuitry 220 may be embodied as software, firmware, hardware or any combination thereof. Processing circuitry 220 may include, for instance, a variety of capacitors, transformers, switches, and the like configured to perform the functions of processing circuitry 220. In examples, processing circuitry 220 may be configured to communicate (e.g., via communication circuitry 228) with another device, such as a patient input / output device, a clinician input / output device, and / or others. Processing circuitry 220 may include any suitable hardware, firmware, software or any combination thereof for communicating with another device. In addition, processing circuitry 220 may communicate with a networked computing device and a computer network.

[0119] In some examples, processing circuitry 220 may receive (e.g., from an external device), via communication circuitry 228, a respective value for each of a plurality of cardiac sensing parameters, cardiac therapy parameters (e.g., cardiac pacing parameters), and / or electrode vectors. Processing circuitry 220 may store such parameters and / or electrode vectors in memory 230. Therapy delivery circuitry 224 and sensing circuitry 222Atty Ref. No: A0011305WO01 are electrically coupled to electrodes 232, which may correspond to first electrode 138, second electrode 139, device electrodes 111, and / or other electrodes electrically connected to and / or supported by device 218. Processing circuitry 220 is configured to control therapy delivery circuitry 224 to generate and deliver electrical therapy to heart 101 via electrodes 232. Electrical therapy may include, for example, pacing pulses, or any other suitable electrical stimulation. Processing circuitry 220 may control therapy delivery circuitry 224 to deliver electrical stimulation therapy via electrodes 232 according to one or more therapy parameter values, which may be stored in memory 230. Therapy delivery circuitry 224 may include capacitors, current sources, and / or regulators, in some examples.

[0120] In addition, processing circuitry 220 is configured to control sensing circuitry 222 to monitor signals from electrodes 232 in order to monitor electrical activity of heart 101. Sensing circuitry 222 may include circuits that acquire electrical signals, such as filters, amplifiers, and analog-to-digital circuitry. Electrical signals acquired by sensing circuitry 222 may include intrinsic and / or paced cardiac electrical activity, such as atrial depolarizations and / or ventricular depolarizations. Sensing circuitry 222 may filter, amplify, and digitize the acquired electrical signals to generate raw digital data. Processing circuitry 220 may receive the digitized data generated by sensing circuitry 222. In some examples, processing circuitry 220 may perform various digital signal processing operations on the raw data, such as digital filtering. In some examples, in addition to sensing circuitry 222, device 218 optionally may include sensors 226, which may one or more pressure sensors and / or one or more accelerometers, as examples. Communication circuitry 228 may include any suitable hardware (e.g., an antenna), firmware, software, or any combination thereof for communicating with another device, e.g., external to the patient.

[0121] IMD housing 196 may enclose processing circuitry 134 and / or other circuitry within medical system 100. IMD housing 196 may be configured to fluidly isolate processing circuitry 134 and / or other circuitry from an environment in contact with an exterior surface of IMD housing 196. In examples, IMD housing 196 is configured to hermetically seal an enclosure defined by IMD 102 and holding processing circuitry 134 and / or other circuitry. IMD housing 196 may be configured to define shapes that are easily accepted by the patient's body while minimizing patient discomfort. For example, IMD housing 196 may define a substantially cylindrical shape with cylindrical sidewalls.Atty Ref. No: A0011305WO01 In other examples, IMD housing 196 may define substantially rectangular or other non- cylindrical shapes. IMD housing 196 may define shapes in which corners and edges are designed with relatively large radii, in order to present a housing having smoothly contoured exterior surfaces. In examples, attachment member 132 is coupled to IMD housing 196.

[0122] Communication links 157, 161 may be hard-line and / or wireless communications links. In some examples, communication links 157, 161 may comprise some portion of control circuitry 220. In some examples, communication links 157, 161 comprise a wired connection, a wireless Internet connection, a direct wireless connection such as wireless LAN, BluetoothTM, Wi-FiTM, and / or an infrared connection. Communication links 157, 161 may utilize any wireless or remote communication protocol. Conductive links 135, 137 may be any component configured to conduct an electrical signal over a conductive pathway.

[0123] As used here, when a first portion of a system (e.g., medical system 100) supports a second portion of the system, this means that when the second portion causes a first force to be exerted on the first portion, the first portion causes a second force to be exerted on the second portion in response to the first force. The first force and / or second force may be a contact force and / or an action-at-a-distance force. For example, first force and / or second force may be mechanical force, a magnetic force, a gravitational force, or some other type of force. The first portion of the system may be a portion of the system or a portion of a component of the system. The second portion of the system may be another portion of the system or another portion of the same component or a different component. In some examples, when the first portion of the system supports the second portion of the system, this may mean the second portion is mechanically supported by and / or mechanically connected to the first portion.

[0124] Various examples of the disclosure have been described. Any combination of the described systems, operations, or functions is contemplated. These and other examples are within the scope of the following claims.

[0125] Example 1. A medical system including a device tether, the device tether comprising: a tether electrode configured to receive an intrinsic electrical signal produced by a heart of a patient, a tether head configured to engage an implantable medical device within a chamber of the heart, an electrically conductive tether including a tether distalAtty Ref. No: A0011305WO01 portion configured to be intracorporeal to a patient and a tether proximal portion configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal, wherein the tether head is attached to the tether distal portion, and wherein at least one of the tether head or the tether distal portion supports the tether electrode.

[0126] Example 2. The medical system of Example 1, further comprising processing circuitry configured to receive the intrinsic electrical signal from the tether proximal portion, wherein the device tether is configured to conduct the intrinsic electrical signal to the tether proximal portion.

[0127] Example 3. The medical system of Example 1 or Example 2, further comprising a first electrode configured to electrically connect to the tether proximal portion and a second electrode configured to connect to a portion of the patient, wherein the processing circuitry is configured to receive the intrinsic electrical signal using the first electrode and the second electrode.

[0128] Example 4. The medical system of any of Examples 1–3, further comprising a display device in communication with the processing circuitry, wherein the display device is configured to provide a visual indication of the intrinsic electrical signal using the communication.

[0129] Example 5. The medical system of any of Examples 1–4, wherein at least a portion of the processing circuitry is supported by an external device configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal.

[0130] Example 6. The medical system of any of Examples 1–5, wherein at least a portion of the processing circuitry is supported by the implantable medical device.

[0131] Example 7. The medical system of any of Examples 1–6, wherein the tether head supports the tether electrode.

[0132] Example 8. The medical system of any of Examples 1–7, wherein the tether electrode is defined by at least one of a body of the tether head or a body of the tether distal portion.

[0133] Example 9. The medical system of any of Examples 1–8, wherein the intrinsic electrical signal is an intracardiac electrogram.

[0134] Example 10. The medical system of any of Examples 1–9, furtherAtty Ref. No: A0011305WO01 comprising a delivery catheter including a catheter distal portion and a catheter proximal portion, wherein the catheter distal portion is configured to be intracorporeal to the patient and the catheter proximal portion is configured to be extracorporeal to the patient when the catheter distal portion is intracorporeal, wherein the delivery catheter defines a delivery lumen extending between a distal lumen opening defined by the catheter distal portion and a proximal lumen opening defined by the catheter proximal portion, and wherein the tether distal portion is configured to pass through the distal lumen opening and the tether proximal portion is configured to pass through the proximal lumen opening when the conductive tether translates within the delivery lumen,.

[0135] Example 11. The medical system of Example 10, further comprising a device receptacle including a receptacle wall defining a receptacle volume, wherein the distal lumen opening opens into the receptacle volume, and wherein the device receptacle is configured to position within the chamber of the heart.

[0136] Example 12. The medical system of Example 11, wherein the tether electrode is configured to receive the intrinsic electrical signal when the tether electrode is positioned in one of the receptacle volume or the delivery lumen.

[0137] Example 13. The medical system of Example 11 or Example 12, further comprising the implantable medical device, wherein the implantable medical device is configured to position within the receptacle volume when the tether head is engaged with the implantable medical device.

[0138] Example 14. The medical system of Example 13, wherein the implantable medical device includes a distal electrode and a proximal electrode, wherein the implantable medical device is configured to receive the intrinsic electrode signal using at least one of the proximal electrode or the distal electrode, and wherein the tether electrode is configured to receive the intrinsic electrical signal when at least the proximal electrode is positioned within the receptacle volume.

[0139] Example 15. The medical system of any of Examples 1–14, wherein the conductive tether defines an outer surface extending from the tether distal portion to the tether proximal portion, and wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion using the outer surface.

[0140] Example 16. The medical system of Example 15, wherein the first electrode of claim 3 is configured to electrically connect to the outer surface.Atty Ref. No: A0011305WO01

[0141] Example 17. The medical system of any of Examples 1–16 wherein the first electrode of claim 3 includes a conductor configured to establish contact with the tether proximal portion to electrically connect the first electrode and the tether proximal portion, and wherein the first electrode is configured to displace the conductor from the tether proximal portion to electrically isolate the first electrode and the tether proximal portion.

[0142] Example 18. The medical system of Example 17, wherein the first electrode includes a clip configured to cause contact between the conductor and the tether proximal portion in a first clip position and displace the conductor from the tether proximal portion in a second clip position.

[0143] Example 19. The medical system of Example 18, wherein the clip is biased to transition from the second clip position to the first clip position.

[0144] Example 20. The medical system of any of Examples 1–19, wherein the tether head is configured to engage the implantable medical device in an engagement configuration and disengage from the implantable medical device in a disengagement configuration, and further comprising a handle configured to cause the tether head to transition between the engagement configuration and the disengagement configuration.

[0145] Example 21. The medical system of Example 20, wherein the conductive tether includes a tether wall defining a tether lumen extending from the handle to the tether head, and further comprising a wire extending through the tether lumen, wherein the wire is configured to enable the handle to cause the tether head to transition between the engagement configuration and the disengagement configuration.

[0146] Example 22. The medical system of Example 21, wherein the tether wall is configured to conduct the intrinsic electrical signal from the tether distal portion to the tether proximal portion.

[0147] Example 23. The medical system of any of Examples 1–22, further comprising the second electrode, wherein the second electrode is configured to electrically connect to skin of the patient.

[0148] Example 24. A medical system including a device tether, the device tether comprising: a tether electrode configured to receive an intrinsic electrical signal produced by a heart of a patient, a tether head configured to engage an implantable medical device within a chamber of the heart, a conductive tether including a tether distal portionAtty Ref. No: A0011305WO01 configured to be intracorporeal to a patient and a tether proximal portion configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal, wherein the tether head is attached to the tether distal portion, wherein at least one of the tether head or the tether distal portion supports the tether electrode, wherein the tether electrode is configured to conduct the intrinsic electrical signal to the tether distal portion, wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion, and a handle supported by the tether proximal portion, the handle configured to cause the tether head to disengage from the implantable medical device in the chamber of the heart.

[0149] Example 25. The medical system of Example 24, further comprising: a first electrode is configured to electrically connect to the tether proximal portion, wherein the first electrode is configured to receive the intrinsic electrical signal from the tether proximal portion; a second electrode configured to electrically connect to skin of the patient; processing circuitry configured to receive the intrinsic electrical signal using the first electrode and the second electrode; and a display device in communication with the processing circuitry, wherein the display device is configured to provide a visual indication of the intrinsic electrical signal using the communication.

[0150] Example 26. The medical system of Example 24 or Example 25, wherein the conductive tether defines an outer surface extending from the tether head to the tether distal portion and extending from the tether distal portion to the tether proximal portion, wherein the tether head is configured to conduct the intrinsic electrical signal to the tether distal portion using the outer surface, and wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion using the outer surface.

[0151] Example 27. The medical system of Example 26, wherein the first electrode of claim 25 is configured to electrically connect to the outer surface.

[0152] Example 28. The medical system of any of Examples 24–27, further comprising: a delivery catheter including a catheter distal portion and a catheter proximal portion, wherein the catheter distal portion is configured to be intracorporeal to the patient and the catheter proximal portion is configured to be extracorporeal to the patient when the catheter distal portion is intracorporeal, wherein the delivery catheter defines a delivery lumen extending between a distal lumen opening defined by the catheter distal portion and a proximal lumen opening defined by the catheter proximal portion, andAtty Ref. No: A0011305WO01 wherein the tether distal portion is configured to pass through the distal lumen opening and the tether proximal portion is configured to pass through the proximal lumen opening when the conductive tether translates within the delivery lumen; a device receptacle including a receptacle wall defining a receptacle volume, wherein the distal lumen opening opens into the receptacle volume, wherein the device receptacle is configured to position within the chamber of the heart, and wherein the tether electrode is configured to receive the intrinsic electrical signal when the tether head is positioned in one of the receptacle volume or the delivery lumen; and an external device supporting the processing circuitry, wherein the external device is configured to be extracorporeal to the patient when the tether distal portion, the tether head, the device receptacle, and the catheter distal portion are intracorporeal to the patient.

[0153] Example 29. A method, comprising: receiving, using a tether electrode of a device tether including a tether head and a conductive tether located within a chamber of a heart of a patient, an intrinsic electrical signal produced by the heart, wherein the tether head is configured to engage an implantable medical device within the chamber of a heart, wherein the tether electrode is electrically connected to a tether distal portion of the conductive tether, wherein the tether distal portion is electrically connected to a tether proximal portion of the conductive tether, and wherein the tether proximal portion is extracorporeal to the patient; and receiving, using processing circuitry, the intrinsic electrical signal using a first electrode electrically connected to the tether proximal portion and a second electrode electrically connected to a portion of the patient.

[0154] Example 30. The method of Example 29, further comprising: conducting, using the tether electrode, the intrinsic electrical signal to the tether distal portion; and conducting, using the tether distal portion, the intrinsic electrical signal to the tether proximal portion.

[0155] Example 31. The method of Example 29 or Example 30, further comprising providing, using a display device in communication with the processing circuitry, a visual indication of the intrinsic electrical signal.

[0156] Example 32. The method of any of Examples 29–31, further comprising detecting, using the processing circuitry, an intracardiac electrogram using the intrinsic electrical signal.

[0157] Example 33. The method of any of Examples 29–32, further comprisingAtty Ref. No: A0011305WO01 supporting, using an external device extracorporeal to the patient, the processing circuitry.

[0158] Example 34. The method of any of Examples 29–33, further comprising supporting, using an implantable medical device intracorporeal to the patient, the processing circuitry.

[0159] Example 35. The method of any of Examples 29–34, further comprising: extending, using the conductive tether, the tether proximal portion through a proximal lumen opening of a catheter lumen defined by a catheter proximal portion of a delivery catheter, wherein the catheter proximal portion is extracorporeal to the patient, and wherein the delivery lumen extends from the proximal lumen opening to a distal lumen opening of the catheter lumen; and electrically connecting, using the tether proximal portion, the first electrode and a portion of the tether proximal portion which is proximal to the proximal lumen opening.

[0160] Example 36. The method of Example 35, further comprising positioning, using the delivery catheter, a device receptacle within the chamber of the heart, wherein the device receptacle includes a receptacle wall defining a receptacle volume, and wherein the distal lumen opening opens into the receptacle volume.

[0161] Example 37. The method of Example 36, further comprising receiving, using the tether electrode, the intrinsic electrical signal when the tether head is positioned in one of the receptacle volume or the delivery lumen.

[0162] Example 38. The method of Example 36 or Example 37, further comprising engaging, using the tether head, the implantable medical device when the implantable medical device is within the receptacle volume.

[0163] Example 39. The method of any of Examples 36–38, further comprising receiving, using the tether electrode, the intrinsic electrical signal when at least a proximal electrode of the implantable medical device is positioned within the receptacle volume.

[0164] Example 40. The method of Example 38 or Example 39, wherein the processing circuitry is device processing circuitry supported by a device housing of the implantable medical device, and further comprising receiving, using the device processing circuitry, the intrinsic electrical signal.

[0165] Example 41. The method of Example 40, wherein the device processing circuitry is configured to receive the intrinsic electrical signal using at least one of the proximal electrode or a distal electrode of the implantable medical device, and furtherAtty Ref. No: A0011305WO01 comprising electrically connecting, using at least the device housing, the tether electrode and the at least one of the proximal electrode or the distal electrode.

[0166] Example 42. The method of Example 41, further comprising conducting, using the device housing, the intrinsic electrical signal from the tether electrode to the at least one of the proximal electrode or the distal electrode.

[0167] Example 43. The method of any of Examples 40–42, further comprising contacting, using the implantable medical device, the distal electrode with blood of the patient.

[0168] Example 44. The method of any of Examples 36–43, further comprising positioning, using the device receptacle, the implantable medical device between the tether head and a receptacle opening defined by the device receptacle.

[0169] Example 45. The method of any of Examples 29–44, further comprising electrically connecting, using the conductive tether, the tether distal portion and the tether proximal portion using an outer surface extending from the tether distal portion to the tether proximal portion.

[0170] Example 46. The method of Example 45, further comprising electrically connecting, using the conductive tether, the first electrode and the outer surface to electrically connect the first electrode and the tether proximal portion.

[0171] Example 47. The method of any of Examples 29–46, further comprising: contacting, using the first electrode, a conductor of the first electrode and the tether proximal portion to electrically connect the first electrode and the tether proximal portion; and displacing, using the first electrode, the conductor from the tether proximal portion to electrically isolate the first electrode and the tether proximal portion.

[0172] Example 48. The method of any of Examples 29–47, further comprising: maintaining, using a biasing of the first electrode, the electrical contact between the first electrode and the tether proximal portion; and overcoming, using the first electrode, the bias of the first electrode to electrically isolate the first electrode and the tether proximal portion.

[0173] Example 49. The method of any of Examples 29–48, further comprising transitioning, using a handle, the tether head between an engagement configuration wherein the tether head engages the implantable medical device and a disengagement configuration wherein the tether head is disengaged from the implantable medical device.Atty Ref. No: A0011305WO01

[0174] Example 50. The method of Example 49, further comprising enabling, using a wire extending through a tether lumen defined by a tether wall of the conductive tether, the handle to transition the tether head between an engagement configuration and a disengagement configuration.

[0175] Example 51. The method of Example 52, further comprising electrically connecting, using the tether wall, the tether distal portion and the tether proximal portion.

[0176] Example 52. A method, comprising: positioning, using a device receptacle supported by a delivery catheter, an implantable medical device within a chamber of a heart of a patient, wherein the device receptacle defines a receptacle volume holding the implantable medical device and defines a receptacle opening configured to allow the implantable medical device to pass therethrough; supporting, using a tether distal portion of a conductive tether extending through a catheter lumen defined by the delivery catheter, a tether head within the receptacle volume, wherein the implantable medical device is between the tether head and the receptacle opening; receiving, using a tether electrode supported by at least one of the tether head or the tether distal portion, an intrinsic electrical signal produced by the heart; conducting, using the tether electrode, the intrinsic electrical signal to the tether distal portion; conducting, using the tether distal portion, the intrinsic electrical signal to a tether proximal portion of the conductive tether, wherein the tether proximal portion is extracorporeal to the patient; receiving, using processing circuitry supported by an external device extracorporeal to the patient, the intrinsic electrical signal using a first electrode electrically connected to the tether proximal portion and a second electrode electrically connected to a portion of the patient; and providing, using a display device in communication with the processing circuitry, a visual indication of the intrinsic electrical signal.

[0177] Example 53. The method of Example 52, further comprising: electrically connecting, using the tether head, the tether electrode and a device housing of the implantable medical device, wherein the device housing is electrically connected to a proximal electrode of the implantable medical device, and wherein at least some portion of the device housing and the proximal electrode are positioned within the receptacle volume; receiving, using device processing circuitry supported by the implantable medical device and a distal electrode of the implantable medical device, the intrinsic electrical signal; and providing, using an indication device, a visual indication of the intrinsicAtty Ref. No: A0011305WO01 electrical signal detected by the device processing circuitry, wherein the indication device is one of the display device or another device.

[0178] Example 54. The method of Example 53, further comprising receiving the intrinsic electrical signal using the device processing circuitry subsequent to receiving the intrinsic electrical signal using the processing circuitry supported by the external device.

Claims

Atty Ref. No: A0011305WO01 WHAT IS CLAIMED:

1. A medical system including a device tether, the device tether comprising: a tether electrode configured to receive an intrinsic electrical signal produced by a heart of a patient; a tether head configured to engage an implantable medical device within a chamber of the heart; and an electrically conductive tether including a tether distal portion configured to be intracorporeal to a patient and a tether proximal portion configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal, wherein the tether head is attached to the tether distal portion, and wherein at least one of the tether head or the tether distal portion supports the tether electrode.

2. The medical system of claim 1, further comprising processing circuitry configured to receive the intrinsic electrical signal from the tether proximal portion, wherein the device tether is configured to conduct the intrinsic electrical signal to the tether proximal portion.

3. The medical system of claim 1 or claim 2, further comprising a first electrode configured to electrically connect to the tether proximal portion and a second electrode configured to connect to a portion of the patient, wherein the processing circuitry is configured to receive the intrinsic electrical signal using the first electrode and the second electrode.

4. The medical system of any of claims 1–3, further comprising a display device in communication with the processing circuitry, wherein the display device is configured to provide a visual indication of the intrinsic electrical signal using the communication.

5. The medical system of any of claims 1–4, wherein at least a portion of the processing circuitry is supported by an external device configured to be extracorporeal to the patient when the tether distal portion and the tether head are intracorporeal.Atty Ref. No: A0011305WO01 6. The medical system of any of claims 1–5, wherein at least a portion of the processing circuitry is supported by the implantable medical device.

7. The medical system of any of claims 1–6, wherein the tether electrode is defined by at least one of a body of the tether head or a body of the tether distal portion.

8. The medical system of any of claims 1–7, wherein the intrinsic electrical signal is an intracardiac electrogram.

9. The medical system of any of claims 1–8, further comprising a delivery catheter including a catheter distal portion and a catheter proximal portion, wherein the catheter distal portion is configured to be intracorporeal to the patient and the catheter proximal portion is configured to be extracorporeal to the patient when the catheter distal portion is intracorporeal, wherein the delivery catheter defines a delivery lumen extending between a distal lumen opening defined by the catheter distal portion and a proximal lumen opening defined by the catheter proximal portion, and wherein the tether distal portion is configured to pass through the distal lumen opening and the tether proximal portion is configured to pass through the proximal lumen opening when the conductive tether translates within the delivery lumen,.

10. The medical system of claim 9, further comprising a device receptacle including a receptacle wall defining a receptacle volume, wherein the distal lumen opening opens into the receptacle volume, and wherein the device receptacle is configured to position within the chamber of the heart.

11. The medical system of claim 10, further comprising the implantable medical device, wherein the implantable medical device includes a distal electrode and a proximal electrode, wherein the implantable medical device is configured to receive the intrinsic electrode signal using at least one of the proximal electrode or the distalAtty Ref. No: A0011305WO01 electrode, and wherein the tether electrode is configured to receive the intrinsic electrical signal when at least the proximal electrode is positioned within the receptacle volume.

12. The medical system of any of claims 1–11, wherein the conductive tether defines an outer surface extending from the tether distal portion to the tether proximal portion, and wherein the tether distal portion is configured to conduct the intrinsic electrical signal to the tether proximal portion using the outer surface.

13. The medical system of any of claims 1–12, wherein the tether head is configured to engage the implantable medical device in an engagement configuration and disengage from the implantable medical device in a disengagement configuration, and further comprising a handle configured to cause the tether head to transition between the engagement configuration and the disengagement configuration.

14. The medical system of claim 13, wherein the conductive tether includes a tether wall defining a tether lumen extending from the handle to the tether head, and further comprising a wire extending through the tether lumen, wherein the wire is configured to enable the handle to cause the tether head to transition between the engagement configuration and the disengagement configuration.

15. The medical system of claim 14, wherein the tether wall is configured to conduct the intrinsic electrical signal from the tether distal portion to the tether proximal portion.

Images