Delivery and retrieval system for a medical device

Abstract

A medical system including a catch device configured to limit relative movement between a tether assembly configured to engage an implantable medical device and a delivery catheter configured to deliver the implantable medical device. The catch device includes an engagement member configured to engage the tether assembly to limit the relative movement. In examples, the catch device is configured to transition between a capture configuration in which the catch device limits the relative movement and a release configuration in which the catch device allows the relative movement. The catch device may be configured to limit relative movement between the implantable medical device and a receptacle device of the delivery catheter.

Description

Atty Ref. No. A0012365WO01 DELIVERY AND RETRIEVAL SYSTEM FOR A MEDICAL DEVICE

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No.63 / 692,893, filed September 10, 2024, the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] This disclosure relates generally to medical devices, and, more particularly, to systems for delivering 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] In an example, a medical system comprises: a tether head configured to engageAtty Ref. No. A0012365WO01 with and disengage from an implantable medical device; a tether including a tether body affixed to the tether head; and a catch device including a housing supporting an engagement member, wherein the engagement member is configured to exert a force on the tether body to cause an engagement (e.g., a frictional engagement) between the engagement member and the tether body, wherein the housing is configured to remain substantially stationary with respect to a portion of the tether body when the engagement member exerts the force on the tether body, and wherein the housing is configured to abut a catheter proximal portion of a delivery catheter, the delivery catheter configured to hold the implantable medical device in a catheter distal portion when the engagement member exerts the force on the tether body and the housing abuts the delivery catheter proximal portion.

[0006] In an example, a medical system comprises: a tether head configured to engage with and disengage from an implantable medical device; a tether including a tether body defining a tether proximal portion and a tether distal portion affixed to the tether head; a catch device including a housing supporting an engagement member, wherein the engagement member is configured to exert a force on the tether proximal portion to cause an engagement between the engagement member and the tether body, wherein the housing is configured to remain substantially stationary with respect to a portion of the tether proximal portion when the engagement member exerts the force on the tether body; and a delivery catheter, wherein the delivery catheter includes a catheter body defining a catheter lumen, wherein the tether body is configured to extend within the catheter lumen, wherein the housing is configured to abut a proximal portion of the delivery catheter, and wherein the delivery catheter configured to hold the implantable medical device in a distal portion of the delivery catheter when the engagement member exerts the force on the tether body and the housing abuts the proximal portion of the delivery catheter.Atty Ref. No. A0012365WO01

[0007] In an example, a method comprises: imparting, using an engagement member of a catch device, a force on a tether body extending through a delivery lumen of a delivery catheter to cause an engagement member to engage (e.g., frictionally engage) the tether body, wherein the tether body supports a tether head configured to engage with and disengage from an implantable medical device; and holding, using the force, a portion of tether body substantially stationary with respect to a portion of the delivery catheter by abutting a housing of the catch device against the delivery catheter.

[0008] 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. BRIEF DESCRIPTION OF DRAWINGS

[0009] FIG.1 is a conceptual drawing illustrating portions of patient anatomy including potential implant sites for an implantable medical device (IMD).

[0010] FIG.2 is a schematic illustration depicting an example medical device delivery system for delivering an IMD to a location within a heart.

[0011] FIG.3 is a schematic illustration of an IMD within a receptacle volume of a receptacle device supported by a delivery catheter, with the receptacle device and delivery catheter shown as transparent for clarity.

[0012] FIG.4 is a perspective view of an example catch device.

[0013] FIG.5 is a cross-sectional perspective view of the example catch device.

[0014] FIG.6 is a cross-sectional plan view of the example catch device in a release configuration.

[0015] FIG.7 is a cross-sectional end view of a portion of the example catch device in the release configuration.

[0016] FIG.8 is a cross-sectional plan view of the example catch device in a capture configuration.

[0017] FIG.9 is a cross-sectional end view of a portion of the example catch device in the capture configuration.

[0018] FIG.10 is a cross-sectional plan view of a second example catch device.Atty Ref. No. A0012365WO01

[0019] FIG.11 is a cross-sectional plan view of a third example catch device.

[0020] FIG.12 is a cross-sectional plan view of a fourth example catch device.

[0021] FIG.13 is a cross-sectional plan view of a fifth example catch device.

[0022] FIG.14 is a perspective view of another example catch device.

[0023] FIG.15 is a cross-sectional perspective view of the catch device of FIG.14.

[0024] FIG.16 is a is a cross-sectional end view of a portion of the catch device of FIG.14 and FIG.15.

[0025] FIG.17 is a schematic illustration depicting a tether head.

[0026] FIG.18 illustrates an example technique for operating a catch device. DETAILED DESCRIPTION

[0027] This disclosure describes a medical system configured to deliver, position, and / or retrieve an medical device (e.g., an implantable medical device) within an anatomical volume (e.g., a chamber of a heart) within a patient. In examples, the medical system includes a receptacle device configured to hold the medical device during, for example, transit through vasculature of a patient. The medical system is configured to constrain movement of the medical device relative to the receptacle device to limit incidental movement between the medical device and the receptacle device which might otherwise occur. For example, the medical system may constrain relative motions between the medical device and the receptacle device that otherwise might occur as the receptacle device and medical device transit over a curving path through the vasculature enroute to a target site. Such relative motions could potentially cause undesired repositioning of the medical device within the receptacle device during the transit. For example, such relative motions might cause a slight extension of the medical device from a distal end of the receptacle device, and / or cause other repositioning of the medical device enroute to the target site.

[0028] The medical system may include a tether assembly configured to cause a tether head device to engage with and / or disengage from the medical device (e.g., as the medical device is held within a receptacle volume defined by the receptacle device). In examples, the tether head is supported by an elongate tether configured to extend through a lumen of a delivery catheter (“delivery catheter lumen”) supporting the receptacle device. The receptacle device may define a receptacle opening (e.g., at a distal end) which opens intoAtty Ref. No. A0012365WO01 the receptacle volume to, for example, allow the medical device to pass out of or into the receptacle volume. The tether head may be configured to engage the medical device within receptacle volume when the tether body extends through the delivery catheter lumen.

[0029] The medical system may be configured such that, when the tether head is engaged with the medical device and the medical device resides within the receptacle volume, translation of the tether relative to the delivery catheter cause a translation of the tether head relative to the receptacle device, and may cause corresponding translation of the medical device relative to the receptacle device. For example, the medical system may be configured that translation of the tether (e.g., as the tether extends through the delivery catheter lumen) in a distal direction relative to the delivery catheter causes the medical device to translate relative to the receptacle device in the distal direction. The medical system may be configured that translation of the tether in a proximal direction relative to the delivery catheter causes the medical device to translate relative to the receptacle device in the proximal direction. Hence, translation of the tether relative to the delivery catheter (e.g., in the distal direction) may be utilized to cause the medical device to translate through the receptacle opening to exit the receptacle volume for implantation of the medical device at target site within a patient. Translation of the tether body relative to the delivery catheter (e.g., in the proximal direction) may be utilized to cause the medical device to translate through the receptacle opening to enter the receptacle volume for retrieval of the medical device from a target site within a patient.

[0030] The medical system includes a catch device configured to constrain movement of the medical device relative to the receptacle device to, for example, limit incidental movement between the medical device and the receptacle device during transit through the vasculature. In examples, the catch device is configured to limit relative translation (e.g., sliding translation) between the tether and the delivery catheter to limit incidental movement between the medical device and the receptacle device.

[0031] The catch device may be configured establish a capture configuration to limit to the relative translation between the tether and the delivery catheter. In some examples, the catch device is configured to establish a release configuration to substantially allow relative translation between the tether and the delivery catheter (e.g., to enable deployment and / or retrieval of the medical device via the receptacle opening). The catch device may be operable by a clinician to cause the catch device to establish the capture configuration,Atty Ref. No. A0012365WO01 establish the release configuration, and / or transition between the capture configuration and the release configuration. Hence, the medical system may be configured such the clinician may cause the catch device to remain in the capture configuration during transit of the medical device through vasculature (e.g., to constrain movement of the medical device relative to the receptacle device), and cause the catch device to transition to and / or remain in the release configuration in proximity to a target site (e.g., to allow movement of the medical device relative to the receptacle device for delivery and / or retrieval).

[0032] The catch device includes an engagement member supported by a housing of the catch device (“catch device housing”). The catch device is configured to cause the engagement member to exert a force on the tether to limit translation of the tether relative to the delivery catheter. In examples, the engagement member contacts the tether to exert the force on the tether. The engagement member may be configured such that the force causes (or increases) an engagement (e.g., a frictional engagement) between the engagement member and the tether, such that relative motion between the catch device housing and the tether is limited. The catch device housing is configured to substantially abut (e.g., contact) a proximal portion of the delivery catheter when the engagement member engages the tether. Hence, the catch device is configured such that, as the engagement member limits relative motion between the catch device housing and the tether, the catch device housing may abut the proximal portion of the delivery catheter (“delivery catheter proximal portion”) to limit relative motion between the catch device housing and the delivery catheter. The limited motion between the catch device housing and the delivery catheter (which may support the receptacle device) concurrent with the limited motion between the catch device housing and the tether (which supports a tether head engaging the medical device) may act to limit relative motion between the receptacle device and the medical device. In some examples, the catch device is substantially a tensioning device configured to place and / or maintain a tension on the tether body when the engagement member engages the tether body and the catch device housing abuts the deliver catheter.

[0033] In examples, the catch device housing is configured to surround at least some portion (e.g., substantially all of) of an outer perimeter of the tether of the tether assembly. The catch device housing may be configured to be grasped by a clinician and caused to slide over the tether in the proximal direction (e.g., away from the delivery catheter) or inAtty Ref. No. A0012365WO01 the distal direction (e.g., toward the delivery catheter). In examples, the tether is coupled to and / or supports the tether head using a distal portion of the tether (“tether distal portion”) and supports a handle assembly using a proximal portion of the tether (“tether proximal portion”). The handle assembly may be configured to cause the tether head assembly to engage with and / or remain engaged with the medical device, and / or cause the tether head assembly to disengage from and / or remain disengaged from the medical device. In examples, the catch device housing is configured to surround the outer perimeter of the tether between the handle assembly and the tether head. In examples, when the tether extends through the delivery catheter lumen, the catch device housing is configured to surround the outer perimeter of the tether between the handle assembly and the delivery catheter proximal portion.

[0034] In some examples, some portion of the engagement member may be configured to move relative to the catch device housing to exert the force on the tether and cause (or increase) the engagement between the engagement member and the tether. For example, the engagement member may be configured to establish a hold position relative to the catch device housing and establish a slide position relative to the catch device housing. The engagement member may be configured to exert (or increase) the force on the tether in the hold position, such that the engagement between the engagement member and the tether tends to keep the catch device housing substantially stationary relative to the tether (and thus, in examples, tends to limit relative motion between the medical device and the receptacle device). The engagement member may be configured to reduce (e.g., to substantially eliminate) the force on the tether in the slide position, such that engagement between the engagement member and the tether reduces (e.g., ceases) and tends to allow relative motion between the catch device housing and the tether (and thus, in examples, allows relative motion between the medical device and the receptacle device).

[0035] In some examples, the catch device includes an actuator operable by a clinician to cause the engagement member to establish the hold position, establish the slide position, and / or transition between the hold position and the slide position. In examples, the actuator is configured to move relative to the catch device housing to cause the engagement member to establish the hold position, establish the slide position, and / or transition between the hold position and the slide position. For example, the actuator may be configured to contact the engagement member and alter a member force on theAtty Ref. No. A0012365WO01 engagement member when the actuator moves relative to the catch device housing. The engagement member may be configured to transition between the hold position and the slide position when the actuator alters the member force. In some examples, the actuator may be a button configured to displace toward and / or away from the catch device housing when the actuator moves relative to the catch device housing. In some examples, the actuator may be configured to rotate relative to the catch device housing when the actuator moves relative to the catch device housing. The actuator may be configured to move relative to the catch device housing in other manners in other examples.

[0036] In other examples, the engagement member may be configured to remain substantially stationary relative to the catch device housing in the capture configuration of the catch device and in the release configuration of the catch device. For examples, the engagement member may comprise a compressive member configured to compress and exert the force on the tether when the engagement member contacts the tether. The catch device housing may be configured to cause the compressive member to contact the tether when the catch device housing surrounds the outer perimeter of the tether. For example, the these examples, the engagement member may be an O-ring or other compressive member configured to surround and compress against the outer perimeter. The compression may cause the engagement member (e.g., the O-ring) to exert the force on the tether, such that, when the catch device housing abuts the delivery catheter proximal portion, the catch device tends to limit movement between the tether and the delivery catheter to, for example, limit movement between the medical device and the receptacle device. The engagement member may be configured such a clinician may cause the catch device to displace from the delivery catheter (e.g., by pulling the catch device over the tether and away from delivery catheter proximal portion) such that the displacement allows movement between the tether and the delivery catheter to, for example, allow movement between the medical device and the receptacle device.

[0037] Hence, the catch device may be configured to constrain movement of the medical device relative to the receptacle device to limit incidental movement between the medical device and the receptacle device which might otherwise occur as, for example, the receptacle device and medical device transit over a curving path through the vasculature enroute to a target site. The catch device may be operable by a clinician to cause the catch device to establish the capture configuration, establish the release configuration, and / orAtty Ref. No. A0012365WO01 transition between the capture configuration and the release configuration. Thus, the medical system may be configured such the clinician may cause the catch device to remain in the capture configuration during transit of the medical device through vasculature (e.g., to constrain movement of the medical device relative to the receptacle device), and cause the catch device to transition to the release configuration in proximity to a target site (e.g., to allow movement of the medical device relative to the receptacle device for delivery and / or retrieval).

[0038] 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.

[0039] In some examples, medical system 100 includes a delivery catheter 106 supporting a receptacle device 108. Receptacle device 108 is configured to hold IMD 102 during delivery, deployment, and / or retrieval of IMD 102. Receptacle device 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, receptacle device 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 receptacle device 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.

[0040] Delivery catheter 106 is configured to deliver receptacle device 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 receptacle device 108 during advancement of delivery catheter 106 to the anatomical volume, or IMD 102 can be advanced to receptacle device 108 after delivery catheter 106 including receptacle deviceAtty Ref. No. A0012365WO01 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, 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 receptacle device 108 and / or IMD 102 from the anatomical volume of the patient.

[0041] Delivery catheter 106 includes a distal portion 114 (“delivery catheter distal portion 114”) and a proximal portion 116 (“delivery catheter proximal portion 116”). In examples, delivery catheter distal portion 114 is configured to be intracorporeal to the patient. Delivery catheter proximal portion 116 may be configured to 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) receptacle device 108. In examples, delivery catheter 106 is configured to deliver and / or retrieve receptacle device 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.

[0042] In examples, medical system 100 includes a tether system 120 configured to engage IMD 102 when, for example, IMD 102 is positioned within receptacle volume 112. Tether system 120 can be used to, e.g., advance IMD 102 distally from receptacle device 108, through receptacle opening 109, to deploy IMD 102 into the anatomical volume. Tether system 120 can also be used to, e.g., extract and / or retract IMD 102 from the anatomical volume, through receptacle opening 109, into receptacle device 108. Tether system 120 includes a tether body 122 which defines a distal portion 124 (“tether distal portion 124”) and a proximal portion 126 (“tether proximal portion 126”). Tether distal portion 124 may be configured to be intracorporeal to the patient. Tether proximal portion 126 may be configured to be extracorporeal to the patient when tether distal portion 124 is intracorporeal.

[0043] In examples, tether body 122 is configured to extend through delivery lumen 118. In some examples, tether body 122 is configured to extend through delivery lumen 118 and into receptacle volume 112. For example, in FIG.1, portions of tether body 122 within delivery lumen 118 and / or receptacle volume 112 (e.g., a portion of tetherAtty Ref. No. A0012365WO01 proximal portion 126 and tether distal portion 124) are shown with a dashed line, while portions of tether body 122 outside of delivery lumen and / or receptacle volume 112 (e.g., a portion of tether proximal portion 126) are shown with a solid line. In examples, tether body 122 is configured to translate (e.g., slidably translate) and / or rotate relative to delivery catheter 118 when tether body 122 extend throughs delivery lumen 118. For example, tether body 122 may be configured such that a force F1 in a first direction imparted to tether body proximal portion 126 (e.g., by a clinician) causes tether body 122 to translate relative delivery catheter 106 in a distal direction D. Tether body 122 may be configured such that a force F2 in a second direction opposite the first direction imparted to tether body proximal portion 126 (e.g., by the clinician) causes tether body 122 to translate relative delivery catheter 106 in a proximal direction P. Tether body 122 may be configured such that a torque T1 in a first rotational direction (e.g., a clockwise direction) imparted to tether body proximal portion 126 (e.g., by the clinician) causes tether body 122 to rotate in the first rotational direction relative delivery catheter 106, and / or such that a torque T2 in a second rotational direction (e.g., a counter-clockwise direction) imparted to tether body proximal portion 126 (e.g., by the clinician) causes tether body 122 to rotate in the second rotational direction relative delivery catheter 106.

[0044] Tether system 120 and / or component(s) thereof, such as tether distal portion 124 and / or tether proximal portion 126, can comprise any suitable catheter, elongate member, and / or inner member (e.g., relative to delivery catheter 106). Tether system 120 and / or tether body 122 can possess sufficient column strength or ”pushability” to advance IMD 102 distally from receptacle device 108, e.g., in the process of deployment, and / or, in some embodiments, to advance IMD 102, or tether system 120 itself without IMD 102 attached thereto, along the length of delivery catheter 106 including proximal portion 116 and distal portion 114 thereof. Tether system 120 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 receptacle device 108, and / or, in some embodiments, through the length of delivery catheter 106 including proximal portion 116 and distal portion 114 thereof. Tether system 120 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 otherAtty Ref. No. A0012365WO01 component(s) perform the screwing / unscrewing function, tether system 120 and / or tether body 122 need not possess this capability.

[0045] Tether distal portion 124 supports and / or is attached to a tether head 128. Tether head 128 may be configured to engage IMD 102 and / or disengage from IMD 102. In examples, tether head 128 is configured to establish an engagement configuration to engage and / or remain engaged to IMD 102. Tether head 128 may be configured to establish a disengagement configuration to disengage and / or remain disengaged from IMD 102. In examples, tether head 128 is configured to transition between the engagement configuration and the disengagement configuration (e.g., transition from the engagement configuration to the disengagement configuration and / or transition from the disengagement configuration to the engagement configuration).

[0046] Tether head 128 may be configured to reside within receptacle volume 112 and / or delivery lumen 116 when tether body 122 extends through delivery lumen 116. Tether system 120 may be configured such that the translation and / or rotation of tether body 122 relative to delivery catheter 106 causes a translation and / or rotation of tether head 128 relative to delivery catheter 106. For example, tether system 120 may be configured such that translation and / or rotation of tether body 122 relative to delivery catheter 106 in the first direction, the second direction, the first rotational direction, or the second rotational direction causes tether head 128 move relative to delivery catheter 106 in the first direction, the second direction, the first rotational direction, or the second rotational direction respectively.

[0047] Tether system 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 (e.g., when tether head 128 is engaged with IMD 102), such that IMD 102 translates and / or rotates relative to receptacle wall 110. For example, tether system 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. Tether system 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 beAtty Ref. No. A0012365WO01 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, tether head 128, and IMD 102 positioned within delivery lumen 118 and / or receptacle volume 112 are depicted with dashed lines.

[0048] Although IMD 102 is depicted in FIG.1 as partially within receptacle volume 112, in some examples, IMD 102 and / or receptacle device 108 may be configured such that IMD 102 may position wholly within receptacle volume 112. For example, IMD 102 and / or receptacle device 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. Tether system 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.

[0049] In some examples, tether system 120 includes a handle assembly 134 (“tether handle assembly 134”) configured to cause tether head 128 to establish and / or maintain the engagement configuration, establish and / or maintain the disengagement configuration, and / or transition between the engagement configuration and the disengagement configuration. In examples, tether body 122 (e.g., tether distal portion 124) supports tether handle assembly 134. For example, tether handle assembly 134 may include a housing 136 (“tether handle housing 136”). Tether system 120 may be configured such that tether distal portion 124 is engages and / or is affixed to tether handle housing 136. In some examples, tether handle housing 136 engages and / or is affixed to a distal end of tether distal portion 124. In some examples, tether handle assembly 134 includes an actuator 138 (“tether handle actuator 138”) configured to be operable by a clinician to cause tether head 128 to establish and / or maintain the engagement configuration, establish and / or maintain the disengagement configuration, and / or transition between the engagement configuration and the disengagement configuration. In examples, tether handle actuator 138 is configured to move relative to tether handle housing 136 to cause tether head 128 to transition between the engagement configuration and the disengagement configuration. Hence, tether systemAtty Ref. No. A0012365WO01 120 may be configured such that a clinician may cause tether head 128 (e.g., using tether handle assembly 134) to remain in the engagement configuration as delivery catheter 106 transits IMD 102 through vasculature enroute to or during withdrawal from target site 104. Tether system 120 may be configured such that the clinician may cause tether head 128 (e.g., using tether handle assembly 134) to transition from the engagement configuration to the disengagement configuration when delivery catheter 106 is in proximity to target site 104 (e.g., following implantation of IMD 102).

[0050] Medical system 100 includes a catch device 140 including a housing 142 (“device housing 142”). Catch device 140 is configured to constrain movement of IMD 102 relative to receptacle device 108 to, for example, limit incidental movement between IMD 102 and receptacle device 108 during transit through the vasculature. In examples, catch device 140 is configured to limit relative translation (e.g., sliding translation) between tether body 122 and delivery catheter 106 (e.g., delivery catheter body 147 (FIG. 2)) to limit incidental movement between IMD 102 and receptacle device 108. Catch device 140 may be configured to establish a capture configuration to limit the relative translation between tether body 122 and delivery catheter 106, and / or configured to establish a release configuration to substantially allow relative translation between tether body 122 and delivery catheter 118. In examples, catch device 140 may be operable by a clinician to cause catch device 140 to establish the capture configuration, establish the release configuration, and / or transition between the capture configuration and the release configuration.

[0051] For example, catch device 140 may include an actuator 144 (“device actuator 144”) configured to be operable by a clinician to cause catch device 140 to establish and / or maintain the capture configuration, establish and / or maintain the release configuration, and / or transition between the capture configuration and the release configuration. In examples, device actuator 144 is configured to move relative to device housing 142 to cause tether head 128 to transition between the capture configuration and the release configuration. Hence, medical system 100 may be configured such that a clinician may cause catch device 140 (e.g., using device actuator 144) to remain in the capture configuration to limit translation between IMD 102 and receptacle device 108 as delivery catheter 106 transits through vasculature enroute to or during withdrawal from target site 104. Medical system 100 may be configured such that the clinician may causeAtty Ref. No. A0012365WO01 catch device 140 (e.g., using device actuator 144) to transition from the capture configuration to the release configuration when delivery catheter 106 (e.g., delivery catheter distal portion 114) is in proximity to target site 104 (e.g., to allow tether system 120 to deploy IMD 102 via receptacle opening 109).

[0052] Catch device 140 may be configured to exert a force on tether body 122 (e.g., tether proximal portion 126) to limit and / or constrain movement of IMD 102 relative to receptacle device 108. In examples, catch device 140 is configured to limit and / or constrain movement of tether body 122 relative to delivery catheter 106 to limit and / or constrain movement of tether head 128 relative to delivery catheter 106, and thereby (e.g., when tether head engages IMD 102) limit and / or constrain movement of IMD 102 relative to receptacle device 108. In examples, device housing 142 is configured to substantially abut (e.g., contact) delivery catheter proximal portion 116 when catch device 140 exerts the force on tether body 122. Hence, catch device 140 may be configured such that, as catch device 140 limits relative motion between device housing 142 and tether body 122 (e.g., by exerting the force on tether body 122), the device housing 142 may abut delivery catheter proximal portion 116 to limit relative motion between the device housing 142 and delivery catheter 106. The limited motion between device housing 142 and delivery catheter 106 concurrent with the limited motion between the device housing 142 and tether body 122 may act to limit relative motion between IMD 102 and receptacle device 108 (e.g., when tether head 128 engages IMD 102).

[0053] For example, catch device 140 may be configured such that, in the capture configuration, a first force F1 (e.g., in distal direction D) or a second force F2 (e.g., in proximal direction P) imparted to tether body 122 transfers to device housing 142. The transfer of force F1 and / or force F2 to device housing 142 may act to limit relative motion between device housing 142 and tether body 122. Further, device housing 142 may be configured to transfer at least force F1 to delivery catheter proximal portion 116 (e.g., delivery handle housing 150) when force F1 is imparted to tether body 122 and device housing 142 abuts delivery catheter proximal portion 116. Device housing 142 may be configured to receive a reaction force FR-1 from delivery catheter proximal portion 116 in response to transferring force F1 to delivery catheter proximal portion 116.

[0054] The impartation of reaction force FR-1 on device housing 142 when device housing 142 transfers force F1 to delivery catheter distal portion 116 may act to limitAtty Ref. No. A0012365WO01 relative motion between device housing 188 and delivery catheter distal portion 116. Hence, catch device 140 may be configured such that, in the capture configuration, the transfer of at least force F1 from tether body 122 to device housing 142 acts to limit relative motion between the catch device housing 142 and tether body 122, and the impartation of at least reaction force FR-1 from delivery catheter proximal portion 116 acts to limit relative motion between catch device housing 142 and delivery catheter proximal portion 116. The limited motion between catch device housing 142 and delivery catheter proximal portion 116 concurrent with the limited motion between catch device housing 142 and tether body 122 (which supports tether head 128 engaging IMD 102 may act to limit relative motion between receptacle device 108 and IMD 102.

[0055] In examples, catch device 140 is configured to limit the relative translation between tether body 122 and delivery catheter 106 as delivery catheter 106 alters a curvature, and / or defines one or more curvatures (e.g., during transit through vasculature and / or in proximity to target site 104). For example, catch device 140 may be configured to limit the relative translation when a portion of delivery catheter (e.g., delivery catheter distal portion 114) alters its curvature from a first curvature to a second curvature different from the first curvature. Catch device 140 may be configured to limit relative motion between receptacle device 108 and IMD 102 as delivery catheter 106 alters the curvature from the first curvature to the second curvature during transit through vasculature and / or in proximity to target site 104. Catch device 140 may be configured to limit the relative translation when delivery catheter 106 defines a plurality of curvatures. For example, catch device 140 may be configured to limit the relative translation when a first portion of delivery catheter 106 defines the first curvature and a second portion of delivery catheter defines the second curvature. Catch device 140 may be configured to limit relative motion between receptacle device 108 and IMD 102 as delivery catheter 106 defines at least the first curvature and the second curvature during transit through vasculature and / or in proximity to target site 104.

[0056] In examples, the catch device 140 is configured to engage at least some portion (e.g., substantially all) of an outer perimeter defined by tether proximal portion 126 to exert the force on tether body 122 (e.g., when catch device 140 is in the capture configuration). Device housing 142 may be configured to be grasped by a clinician and caused to slide over tether proximal portion 126 in the proximal direction P and / or in theAtty Ref. No. A0012365WO01 distal direction D (e.g., when catch device 140 is in the release configuration). In examples, catch device 140 is configured to engage tether body 122 (e.g., tether proximal portion 126) substantially between tether handle housing 136 and tether head 128. In examples, catch device 140 is configured to engage tether body 122 (e.g., tether proximal portion 126) substantially between tether handle housing 136 and delivery catheter proximal portion 116.

[0057] 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, receptacle device 108 and / or IMD 102 are intracorporeal to the patient.

[0058] IMD processing circuitry 133 may be configured to sense the intrinsic electrical signal using electrodes supported by IMD 102 and / or medical system 100, such as first distal electrode 103, second distal electrode 105, a proximal electrode 107 (e.g., a return electrode), and / or other electrodes of IMD 102 and / or medical system 100. IMD processing circuitry 133 may be configured to process and / or condition a signal sensed by electrodes 103, 105, 107 and / or other electrodes within medical system 100. In examples, one or more electrode (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.

[0059] Tether head 128 and / or tether system 120 may comprise any suitable mating interface or abutment coupled to, or formed on or in tether system 120, The mating interface may be configured to mate with, receive and / or abut a proximal portion of IMD 102. The tether head 128 and / or tether system 120 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 combinationAtty Ref. No. A0012365WO01 thereof, or through some other fixation component(s). The tether head 128 and / or tether system 120 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 tether system 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.

[0060] 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 receptacle device 108 supported by delivery catheter distal portion 114 and tether system 120 extending through delivery lumen 118. In FIG.3, receptacle device 108 and delivery catheter 106 are shown as transparent for clarity.

[0061] Medical system 100 may include an introducer 146, delivery catheter 106, and tether system 120. In examples, introducer 146 is an elongate member defining an interior lumen. Introducer 146 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.

[0062] Delivery catheter 106 includes a body 147 (“delivery catheter body 147”) configured to be inserted through the interior lumen of introducer 146 to deliver IMD 102 (FIG.1) within the vasculature. Delivery catheter 106 includes delivery catheter distal portion 114 and delivery catheter proximal portion 116. In examples, delivery catheter proximal portion 116 includes a handle 148 (“delivery handle 148”) including a housing 150 (“device handle housing 150”). Delivery handle 148 may be configured to allow for ease of manipulation and handling of delivery catheter 106, and / or enable additional functionality of delivery catheter 106 (e.g., steerability of delivery catheter 106). Delivery handle 148 may include one or more elements (such as buttons, switches, etc.) configured to control a motion of (e.g., steer) delivery catheter 106. In examples, delivery lumen 118 extends through delivery handle 148 (e.g., through delivery handle housing 150). In other examples, delivery catheter proximal portion 116 may not necessarily include delivery handle 148.

[0063] Receptacle device 108 is supported by delivery catheter distal portion 114. InAtty Ref. No. A0012365WO01 examples, receptacle device 108 is disposed substantially at a distal end 154 of catheter body 147 (“catheter body distal end 154”). In examples, receptacle wall 110 defines a hollow, substantially cylindrical body defining receptacle volume 112. Receptacle device 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 receptacle device 108 and delivery catheter distal portion 114 through the interior lumen of introducer 146 when introducer 146 is disposed within a vasculature of a patient. Once receptacle device 108 has extended through introducer 146, the clinician may navigate delivery catheter 106 (e.g., using delivery handle 148) 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 tether system 120. The clinician may cause tether head 128 (FIG.1) to disengage from IMD 102 (e.g., using tether handle assembly 134) and proximally withdraw delivery catheter 106 and tether system 120 through introducer 146.

[0064] Tether system 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 (e.g., including delivery handle 148) and / or tether proximal portion 126 is configured to extend through at least delivery catheter proximal portion 116. In FIG.2, portions of tether proximal portion 126 and tether distal portion 124 within delivery lumen 118 are shown with a dashed line.

[0065] 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 128 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).

[0066] Hence, medical system is configured such that axial translation of tether body 122 (e.g., in distal direction D or proximal direction P) relative to delivery catheter 106 may cause an axial translation of IMD 102 relative to receptacle device 108. For example,Atty Ref. No. A0012365WO01 with tether body 122 extending through delivery lumen 118, a translation of tether handle housing 136 relative delivery handle housing 150 in distal direction D (e.g., toward delivery handle housing 150) may cause tether body 122 to translate in distal direction D relative to delivery catheter 106, causing IMD 102 (FIG.1) to translate in distal direction D relative to receptacle device 108. A translation of tether handle housing 136 relative delivery handle housing 150 in proximal direction P (e.g., away from delivery handle housing 150) may cause tether body 122 to translate in proximal direction P relative to delivery catheter 106, causing IMD 102 (FIG.1) to translate in distal direction D relative to receptacle device 108. If the axial translation of tether body 122 relative to delivery catheter 106 is relatively incidental (e.g., caused as a result of relative motion experienced during a transit through vasculature), the relatively incidental relative motion may cause IMD 102 to move within receptacle volume 112 and relative to receptacle device 108 in unintended manners.

[0067] Catch device 140 is configured to limit relative translation (e.g., sliding translation) between tether body 122 and delivery catheter 106 to, for example, limit incidental movement between IMD 102 and receptacle device 108. In examples, catch device 140 is configured to limit and / or constrain movement of device housing 142 relative to tether body 122 limit incidental movement between IMD 102 and receptacle device 108. In examples, device housing 142 is configured to substantially abut (e.g., contact) delivery catheter proximal portion 116 (e.g., delivery handle housing 150) when catch device 140 limits and / or constrains movement of device housing 142 relative to tether body 122. Hence, catch device 140 may be configured such that, as catch device 140 limits relative motion between device housing 142 and tether body 122, the device housing 142 may abut delivery catheter proximal portion 116 to limit relative motion between the device housing 142 and delivery catheter proximal portion 116. The limited motion between device housing 142 and delivery catheter proximal portion 116 concurrent with the limited relative motion between the device housing 142 and tether body 122 may act to limit relative motion between IMD 102 and receptacle device 108 (e.g., when tether head 128 engages IMD 102).

[0068] As used herein, when catch device 140 abuts delivery catheter 106 (e.g., delivery catheter proximal portion 116), this may mean device housing 142 contacts delivery catheter proximal portion 116 (e.g., delivery handle housing 150 or anotherAtty Ref. No. A0012365WO01 portion of delivery catheter proximal portion 116). In examples, device housing 142 is configured such that, when device housing 142 abuts delivery catheter proximal portion 116 and device housing 142 imparts a force in a first direction (e.g., distal direction D) on delivery catheter proximal portion 116, delivery catheter proximal portion 116 imparts a reaction force in a second direction opposite the first direction (e.g., proximal direction P) to limit the motion of device housing 142 relative to delivery catheter 106.

[0069] Delivery catheter proximal portion 116 may optionally comprise a proximal pusher member (not shown) located at the proximal end of delivery catheter proximal portion 116 and projecting in the proximal direction therefrom. Such a proximal pusher member can be biased in the proximal direction relative to delivery catheter proximal portion 116 and configured to abut catch device 140 and exert a proximally directed force against catch device 140. In this manner, the proximal pusher member can provide a positive, proximally-directed force against catch device 140 (and via catch device 140 to tether system 120 and / or tether body 122) and assist in retaining IMD 102 in receptacle device 108. Accordingly, the proximal pusher member can maintain a slight tension in tether body 122 to facilitate maintaining a fully proximal position of IMD 102 in receptacle device 108. The proximal pusher member can optionally comprise a plunger which can be (e.g., longitudinally) movably received in delivery catheter proximal portion 116 (e.g., in delivery handle housing 150, such as in a proximal end wall thereof). The plunger can be spring-biased to a proximal position relative to delivery catheter proximal portion 116 and / or delivery handle housing 150. The proximal pusher member or plunger can optionally include a passageway or lumen through which tether body 122 extends. Such an arrangement allows for the proximal force exerted by the proximal pusher member to be closely aligned with and / or laterally balanced with respect to tether body 122.

[0070] The proximal pusher member and catch device 140 can optionally comprise mating features (not shown) that inhibit lateral movement of the proximal pusher member and catch device 140 relative to each other when catch device 140 abuts the proximal pusher member. For example, such mating features can comprise a longitudinal projection located on one of the proximal pusher member and a distal end of catch device 140 (e.g. on device distal surface 192 of device housing 188), and a closely matching receptacle located on the other of the proximal pusher member and the distal end of catch device 140.Atty Ref. No. A0012365WO01 When such mating features are engaged when the proximal pusher member abuts catch device 140, catch device 140 is inhibited from moving laterally or radially relative to delivery catheter proximal portion 116 due to a close lateral fit of the projection in the receptacle. Where implemented, the passageway or lumen through which tether body 122 extends can pass through the mating features.

[0071] In use, a clinician can activate the proximally directed force generating function of the proximal pusher member by causing catch device 140 to abut delivery catheter proximal portion 116 (specifically, abutting the proximal pusher member) and either slightly compressing the spring (where implemented) of the proximal pusher member or leaving catch device 140 closely abutting the proximal pusher member while IMD 102 is in a fully proximal position within receptacle device 108. In either case, the proximal pusher member will be configured to maintain tension in tether body 122 (and IMD 102 fully within receptacle device 108) via the proximally directed force generated by the proximal pusher member.

[0072] Instead of or in addition to the proximal pusher member described herein, a distal pusher member could be incorporated at device distal surface 192 of device housing 188. Such a distal pusher member and any accompanying structures such as mating features, passageway, etc., can be identical in structure and function to any of the embodiments of the proximal pusher member, etc. described herein, with the noted changes in location and direction of force application relating to the distal pusher member.

[0073] In examples, device housing 142 is configured to be grasped by a clinician and caused to slide over tether proximal portion 126 to cause and / or increase a displacement between device housing 142 and delivery handle housing 150 (e.g., such that device housing 142 ceases to abut delivery handle housing 150). For example, device housing 142 may be slid over tether proximal portion 126 and displaced by a displacement D1 from handle housing 150, such that device housing 142 establishes a second position indicated by dashed lines in FIG.2. In the second position, catch device 140 is configured such that relative motion (e.g., in distal direction D) between tether body 122 and delivery catheter proximal portion 116 (e.g., delivery handle housing 150) may occur, such that relative motion between IMD 102 (FIG.1) and receptacle device 108 may occur. In some examples, device housing 142 is configured to substantially slide over tether proximal portion 126 and displaced by the displacement D1 following operation (e.g., by aAtty Ref. No. A0012365WO01 clinician) of device actuator 144.

[0074] Referring mainly to FIG.3, delivery catheter 106 includes a body 147 (“delivery catheter body 147”) defining delivery lumen 118. Delivery lumen 118 may extend from a distal lumen opening 151 defined by delivery catheter body 147 to a proximal lumen opening 153 defined by delivery catheter body 147. In examples, distal lumen opening 151 opens into receptacle volume 112. In some examples, delivery catheter body 147 defines distal lumen opening 151 substantially at catheter body distal end 154. In some examples, delivery catheter body 147 defines proximal lumen opening 153 substantially at a proximal end 156 of catheter body 147 (“catheter body proximal end 156”). In some examples, delivery catheter handle housing 150 (FIG.2) defines proximal lumen opening 153. In some examples, catheter handle housing 150 is contiguous with and / or a substantially unitary body with delivery catheter body 147.

[0075] Tether system 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 151 as tether body 122 translates within delivery lumen 118. In some examples, tether proximal portion 126 is configured to pass through proximal lumen opening 153 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 153 as tether body 122 translates within delivery lumen 118 (e.g., such that tether head 128 may be withdrawn in its entirety from delivery lumen 118 via proximal lumen opening 153).

[0076] Catch device 140 may define a passage 160 (“device passage 160”) extending from a proximal access 161 defined by device housing 142 (“device proximal access 161”) to a distal access 163 defined by device housing 142 (“device distal access 163”). Catch device 140 may be configured such that device distal access 163 opens into delivery lumen 118 and / or proximal lumen opening 153 when device housing 142 abuts delivery catheter proximal portion 116. Tether body 122 may be configured to extend within device passage 160 from device proximal access 161 to device distal access 163. In examples, tether body 122 is configured to translate (e.g., slidably translate) in the distal direction D and / or in the proximal direction P within device passage 160 (e.g., as tether body 122 translates within delivery lumen 118). In some examples, tether distal portion 124 and / orAtty Ref. No. A0012365WO01 tether head 128 are configured to pass through device passage 160 (e.g., such that tether head 128 may be withdrawn in its entirety from delivery lumen 118 via device passage 160).

[0077] In some examples, device housing 142 defines a longitudinal axis L. In examples, longitudinal axis L extends through device passage 160. In examples, longitudinal axis L extends through device distal access 163 and / or device proximal access 161. In some examples, longitudinal axis L extends at least partially through tether body 122 (e.g., tether proximal portion 126) when tether body 122 extends through device passage 160.

[0078] Tether body 122 may extend from tether handle assembly 134 to tether head 128. Tether head 128 may be attached to and / or affixed to tether distal end 125. In examples, tether handle assembly 134 (e.g., tether handle housing 136) is attached to and / or affixed to a proximal end 127 of tether body 122 (“tether proximal end 127”). In examples, tether body 122 defines a lumen 172 (“tether lumen 172”) extending from tether proximal portion 126 to tether distal portion 124. In examples, tether lumen 172 may extend from a distal tether lumen opening 174 defined by tether distal portion 124 (e.g., tether distal end 125) to a proximal tether lumen opening 176 defined by tether proximal portion 126 (e.g., tether proximal end 127”). In examples, proximal tether lumen 176 opens into an inner volume defined by tether handle assembly 134.

[0079] Tether head 128 is configured to engage IMD 102 in an engagement configuration and disengage from IMD 102 in a disengagement configuration. In examples, tether system 120 includes an elongate body 180 (e.g., a cable) configured to exert a force on tether head 128 to cause tether head 128 to transition between the engagement configuration and the disengagement configuration. For example, in some examples, elongate body 180 is configured to exert the force to cause tether head 128 to transition from the engagement configuration to the disengagement configuration. In some examples, elongate body 180 is configured to exert the force to cause tether head 128 to transition from the disengagement configuration to the engagement configuration. In examples, elongate body 180 is configured to cause tether head 128 to substantially maintain the engagement configuration or the disengagement configuration. For example, elongate body 180 may be configured to exert the force to cause tether head 128 to substantially maintain one of the engagement configuration or disengagementAtty Ref. No. A0012365WO01 configuration. Elongate body 180 may be configured such that, when elongate body 180 ceases to or otherwise does not exert the force, tether head 128 substantially maintains the other of the engagement configuration or disengagement configuration.

[0080] Elongate body 180 may be configured to extend through tether lumen 172. In examples, elongate body 180 includes a distal portion 182 (“elongate body distal portion 182”) configured to attach and / or affix to tether head 128 and / or a proximal portion 184 (“elongate body proximal portion 184”) configured to attach and / or affix to tether handle assembly 134 (e.g., proximal portion 147”). In examples, elongate body 180 (e.g., elongate body proximal portion 184) extends through proximal tether lumen opening 176 and / or into the inner volume of tether handle assembly 134. Elongate body 180 (e.g., elongate body distal portion 182) may extend at least to distal tether lumen opening 174 and / or to tether head 128. Elongate body 180 may be configured to slidably translate within tether lumen 172 when elongate body 180 exerts or ceases to exert the force on tether head 128.

[0081] Tether handle assembly 134 may be configured to cause elongate body 180 to exert the force on tether head 128. For example, tether handle assembly 134 may be configured to exert the force on elongate body 180 in a first direction (e.g., proximal direction P). Elongate body 180 may be configured to transfer the force to tether head 128. Tether handle assembly 134 may be configured to cease exerting the force on elongate body 180 in the first direction, such that elongate body 180 ceases to transfer the force to tether head 128. Hence, tether handle assembly 134 may be configured to cause tether head 128 (e.g., using elongate body 180) to transition between the engagement configuration and the disengagement configuration, and / or to substantially maintain one of the engagement configuration or the disengagement configuration. A clinician may thus use tether handle assembly 134 to cause tether head 128 to engage with and / or disengage from IMD 102 to affect, for example, an implantation or retrieval of IMD 102. In examples, tether handle actuator 138 is configured to cause handle assembly 134 to exert the force on elongate body 180 in the first direction and / or cease exerting the force on elongate body 180 in the first direction.

[0082] Catch device 140 is configured to engage tether body 122 to limit relative motion between device housing 142 and tether body 122. In examples, catch device 140 includes an engagement member 145 configured to engage (e.g., contact) tether body 122.Atty Ref. No. A0012365WO01 Engagement member 145 may be configured to exert a force on tether body 122 to cause and / or increase an engagement (e.g., a frictional engagement) between engagement member 145 and tether body 122 (e.g., tether proximal portion 126). In examples, catch device 140 is configured to limit relative motion between device housing 142 and tether body 122 using the engagement between engagement member 145 and tether body 122. In examples, engagement member 145 is configured to engage tether body 122 (e.g., tether proximal portion 126) within device passage 160. Hence, catch device 140 may be configured such that, when engagement member 145 engages tether body 122 to limit relative motion between device housing 142 and tether body 122, device housing 142 may abut delivery catheter proximal portion 116 to limit relative motion between the device housing 142 and delivery catheter proximal portion 116. The limited motion between device housing 142 and delivery catheter proximal portion 116 concurrent with the limited relative motion between the device housing 142 and tether body 122 may act to limit relative motion between IMD 102 and receptacle device 108 (e.g., when tether head 128 engages IMD 102).

[0083] Engagement member 145 may be configured to engage tether body 122 in any manner. In some examples, engagement member 145 is in contact with tether body 122 when engagement member 145 engages tether body 122. In some examples, when engagement member 145 engages tether body 122, this means engagement member 145 exerts a force on tether body 122 which tether body 122 must overcome to move in distal direction D or proximal direction P. The force may be mechanical force (e.g., a frictional force), a magnetic force, an electromagnetic force, or any other type of force.

[0084] FIG.4 illustrates a perspective view of a catch device 186 including a housing 188 (“device housing 188”) supporting an engagement member configured to engage tether body 122. FIG.5 illustrates a perspective view of catch device 186 with device housing 188 shown as a cross-section. In FIG.5, the cross-section is taken with a cutting plane that includes axis A-A’ of FIG.4 and a longitudinal axis L defined by device housing 188. FIG.6 illustrates a plan view of catch device 186 in a release configuration, with device housing 188 shown as a cross-section with a cutting plane that includes axis A-A’ and longitudinal axis L. FIG.7 depicts a schematic illustration of portion of catch device 186 in the release configuration, with tether body 122 and a contact member shown as cross-section with a cutting plane parallel to the page and including axis B-B’ of FIG.6.Atty Ref. No. A0012365WO01

[0085] FIG.8 illustrates a plan view of catch device 186 with engagement member 202 in a catch configuration, with device housing 188 shown as a cross-section taken with a cutting plane that includes axis A-A’ and longitudinal axis L. FIG.9 depicts a schematic illustration of portion of catch device 186 in the catch configuration, with tether body 122 and a contact member shown as cross-section with the cutting plane parallel to the page and including axis B-B’ of FIG.8. Catch device 186 is an example of catch device 140. Device housing 188 is an example of device housing 142.

[0086] Referring largely to FIG.4 and FIG.5, device housing 188 may define a distal surface 192 (”device distal surface 192”) and a proximal surface 194 (“device proximal surface 194”). In examples, device distal surface 192 is on a first side of device housing 188 and device proximal surface 194 is on a second side of device housing 188 opposite the first side. Catch device 186 may be configured to allow tether body 122 to pass through device distal surface 192 and device proximal surface 194 when tether body 122 passes through device passage 160 (FIG.3).

[0087] In examples, device distal surface 192 is configured to face toward delivery catheter proximal portion 116 (FIG.3) and / or device proximal surface 194 is configured to face toward tether handle assembly 134 when tether body 122 passes through device passage 160. Device housing 188 may define device distal access 163 and / or device proximal access 161. In examples, device distal access 163 opens to device distal surface 192 and device passage 160. In examples, device proximal access 161 opens to device proximal surface 194 and device passage 160. Catch device 186 may be configured such that tether body 122 extends at least from device distal surface 192 to device proximal surface 194 when tether body 122 passes through device passage 160.

[0088] Catch device 186 is configured to engage tether body 122 to limit relative motion between device housing 188 and tether body 122 (e.g., tether proximal portion 126). In examples, device housing 188 is configured such that device distal surface 192 abuts delivery catheter proximal portion 116 (FIG.3) when catch device 186 abuts delivery catheter proximal portion 116 (e.g., abuts delivery handle 148, catheter body proximal end 156, or another portion of delivery catheter 106). Device distal surface 192 may be configured to transfer at least force F1 to delivery catheter proximal portion 116 when force F1 is imparted to tether body 122 and catch device 186 abuts delivery catheter proximal portion 116. Device distal surface 192 may be configured to receive reactionAtty Ref. No. A0012365WO01 force FR-1 from delivery catheter proximal portion 116 in response to transferring force F1 to delivery catheter proximal portion 116. Hence, the impartation of reaction force FR- 1 on device distal surface 192 when device distal surface 192 transfers force F1 to delivery catheter distal portion may act to limit relative motion between device housing 188 and delivery catheter proximal portion 116, thus limiting relative motion between receptacle device 108 and IMD 102.

[0089] Catch device 186 is configured to limit relative motion between tether body 122 and device housing 188 in the capture configuration and substantially allow relative motion between tether body 122 and device housing 188 in a release configuration. In examples, catch device 186 is configured to establish a first frictional force with tether body 122 in the capture configuration and establish a second frictional force less than the first frictional force in the release configuration. In some examples, the second frictional force is substantially zero. Thus, catch device 186 may be configured such that device housing 188 may be more easily displaced (e.g., by a clinician) from delivery catheter proximal portion 116 in the release configuration (e.g., displaced over the displacement D1 (FIG.2)). In examples, catch device 186 is configured such that device housing 188 may slidably translate over tether body 122 (e.g., tether proximal portion 126) in at least the release configuration.

[0090] Catch device 186 includes device actuator 144 configured to be operable by a clinician. Device actuator 144 is configured to cause catch device 140 to establish and / or maintain the capture configuration, establish and / or maintain the release configuration, and / or transition between the capture configuration and the release configuration. In examples, device actuator 144 is configured to move relative to device housing 188 to cause catch device 186 to transition between the capture configuration and the release configuration. In some examples, device housing 188 defines one or more depressions such as depression 196 and / or depression 198 configured to receive some portion of a hand (e.g., one or more fingers) when, for example, a clinician operates device actuator 144 and / or slidably translates catch device 186 over tether body 122.

[0091] Referring largely to FIG.6 and FIG.7, catch device 186 may include an engagement member 202. In examples, engagement member 202 is configured to be disengaged from tether body 122 when catch device 186 is in the release configuration such, for example, tether body 122 may move (e.g., slidably translate) relative to deviceAtty Ref. No. A0012365WO01 housing 188. Engagement member 202 may be configured to engage tether body 122 when catch device 186 is in the capture configuration such that, for example, movement of tether body 122 relative to device housing 188 is limited and / or substantially prevented. Engagement member 202 is an example of engagement member 145. In examples, engagement member 202 is supported by device housing 188.

[0092] In examples, engagement member 202 is configured to impart a first magnitude of force to tether body 122 when engagement member 202 is disengaged from tether body 122 (e.g., when catch device 186 is in the release configuration). Engagement member 202 may be configured to impart a second magnitude of force to tether body 122 when engagement member 202 is engaged with tether body 122 (e.g., when catch device 186 is in the capture configuration). The second magnitude of force may be greater than the first magnitude of force. In some examples, the first magnitude of force may be substantially zero. Hence, engagement member 202 may be configured such that the first magnitude of force (which may be substantially zero) allows movement of tether body 122 relative to device housing 188 in a first direction (e.g., distal direction D). Engagement member 202 may be configured such that the second magnitude of force limits and / or substantially prevents movement of tether body 122 relative to device housing 188 in the first direction (e.g., in the distal direction D).

[0093] In examples, engagement member 202 is configured to establish a slide position relative to device housing 188 and establish a hold position relative to device housing 188. Engagement member 202 may be configured to be disengaged from tether body 122 in the slide position (e.g., configured to exert the first magnitude of force in the slide position). Engagement member 202 may be configured to engage tether body 122 in the hold position (e.g., configured to exert the second magnitude of force in the slide position). Catch device 186 may be configured to cause engagement member 202 to establish the slide position when catch device 186 is in the release configuration and / or be configured to cause engagement member 202 to establish the hold position when catch device 186 is in the capture configuration. In examples, catch device 186 is configured to cause engagement member 202 to transition between the slide position and the hold position when catch device 186 transitions between the release configuration and the capture configuration.

[0094] In examples, and referring largely to FIG.6 and FIG.7, engagement memberAtty Ref. No. A0012365WO01 202 may be configured to be displaced from tether body 122 when engagement member 202 is in the slide position. For example, engagement member 202 may include an engaging portion 210 (FIG.7) configured to be displaced (e.g., by a displacement D2) from tether body 122 when engagement member 202 is in the slide position. Hence, the first magnitude of force exerted on tether body 122 by engagement member 202 may be substantially zero (e.g., due to displacement D2). In other examples, engaging portion 210 may remain in contact with tether body 122 in the slide position but exerting the first magnitude of force less than the second magnitude of force. For example, engagement member 202 may be configured such that, in the release position, engaging portion 210 and tether body 122 remain in sliding contact when tether body 122 moves relative to engagement member 202. Engagement member 202 may impart the first magnitude of force on tether body 122 during the sliding contact.

[0095] In some examples, engagement member 202 defines an aperture 212 configured to receive tether body 122 (e.g., tether proximal portion 126). In examples, tether body 122 is configured to extend through aperture 212 (e.g., when tether body 122 extends through device passage 160). Aperture 212 may define a boundary B configured to at least partially surround tether body 122 when tether body 122 extends through aperture 212. In examples, engaging portion 210 is a portion of boundary B. In some examples, engagement member 202 is configured such that tether body 122 is displaced from boundary B (e.g., does not contact boundary B) when tether body 122 extends through aperture 212 and engagement member 202 is in the slide position. In other examples, engagement member 202 may be configured such that tether body 122 is in sliding contact with boundary B when tether body 122 extends through aperture 212 and engagement member 202 is in the slide position.

[0096] Referring largely to FIG.8 and FIG.9, engagement member 202 is configured to exert the second magnitude of force (e.g., member force FE) on tether body 122 in the hold position. Engagement member 202 may be configured such that when tether body 122 experiences first force F1 in a first direction (e.g., distal direction D), member force FE tends to limit motion of tether body 122 relative to engagement member 202. For example, engagement member 202 may be configured such that at least a component of member force FE acts on tether body 122 in a direction opposite first force F1 (e.g., acts in proximal direction P). Thus, when engagement member 202 is in the hold position,Atty Ref. No. A0012365WO01 engagement member 202 may limit movement of tether body 122 relative to engagement member 202 and / or device housing 188 using member force FE. For example, in the hold position, engagement member 202 may limit movement of tether body 122 relative to engagement member 202 and / or device housing 188 in at least the distal direction D using member force FE. Stated similarly, in the hold position, engagement member 202 may limit movement of device housing 188 relative to tether body 122 (and / or delivery catheter proximal portion 116) in at least the proximal direction P using member force FE.

[0097] In examples, engagement member 202 is configured to cause contact between engaging portion 210 (FIG.9) and tether body 122 when engagement member 202 is in the hold position. Engaging portion 210 may impart member force FE to tether body 122 when engaging portion 210 contacts tether body 122. In some examples, for example when engaging portion 210 is in contact with tether body 122 in the slide position, engagement member 202 may be configured to cause member force FE to have the first magnitude of force in the slide position and have the second magnitude of force in the hold position (e.g., configured to increase member force FE in the hold position).

[0098] Catch device 186 may support engagement member 202 such that, when engagement member 202 imparts member force FE, engagement member 202 transfers a force FH-1 to device housing 188. Force FH-1 may be of substantially equal magnitude and in an opposite direction to the component of member force FE opposing force F1 (e.g., of substantially equal magnitude and in the same direction as force F1). When device distal surface 192 abuts delivery catheter proximal portion 116, device housing 188 may impart force FH-1 on delivery catheter proximal portion 116, causing delivery catheter proximal portion 116 to impart reaction force FR-1 on device housing 188. The impartation of reaction force FR-1 on device housing 188 may limit motion of device housing 188 relative to delivery catheter proximal portion 116 as member force FE limits motion of tether body 122 relative to engagement member 202, such that motion of tether body 122 relative to delivery catheter proximal portion 116 is limited and / or prevented. The limited motion between tether body 122 and delivery catheter proximal portion 116 may tend to limit relative motion between receptacle device 108 (e.g., supported by delivery catheter 106) and IMD 102 (e.g., when engaged with tether head 128).

[0099] In some examples, engagement member 202 is configured such that member force FE limits and / or substantially prevents movement of tether body 122 relative toAtty Ref. No. A0012365WO01 engagement member 202 in the first direction (e.g., distal direction D) and substantially allows movement of tether body 122 relative to engagement member 202 in a second direction (e.g., proximal direction P) opposite the first direction. Stated similarly, engagement member 202 may be configured such that member force FE limits and / or substantially prevents movement of device housing 188 relative to tether body 122 in the second direction (e.g., proximal direction P) and substantially allows movement of device housing 188 relative to tether body 122 in the first direction (e.g., distal direction D).

[0100] For example, engagement member 202 may be configured such that member force FE (e.g., at least when member force FE has the second magnitude of force) causes engagement member 202 to substantially bite tether body 122 when tether body 122 attempts to move in distal direction D relative to engagement member 202. Engagement member 202 may be configured such that member force FE (e.g., even when member force FE has the second magnitude of force) allows slidable translation of engagement member 202 and tether body 122 when tether body 122 moves in proximal P relative to engagement member 202. Thus in some examples, handle device 186 may be configured such that, in the capture configuration, device housing 188 may be moved (e.g., by a clinician) in the second direction (e.g., distal direction D) over tether body 122 and toward catheter proximal portion 116, but movement of device housing 188 in the second direction (e.g., proximal direction P) over tether body 122 and away from catheter proximal portion 116 is limited.

[0101] In examples, engagement member 202 may be configured to bend and / or flex when engagement member 202 transitions between the slide position (FIG.5) and the hold position (FIG.6). For example, engagement member 202 may include a first end 204 attached to device housing 188 and a second end 206 opposite first end 204. In examples, second end 206 is a free end of engagement member 202. First end 204 may be configured (e.g., attached to device housing 188) such that first end 204 remains substantially stationary relative to device housing 188. Second end 206 may be configured to move relative to device housing 188 and / or first end 204 when engagement member 202 transitions from the slide position (FIG.6) to the hold position (FIG.7).

[0102] In examples, catch device 186 includes a contact member 208 configured to cause engagement member 202 to substantially maintain the hold position, substantially maintain the slide position, and / or transition between the hold position and the slideAtty Ref. No. A0012365WO01 position. In examples, contact member 208 is configured to contact engagement member 202 to cause engagement member 202 to substantially maintain the hold position, substantially maintain the slide position, and / or transition between the hold position and the slide position. Contact member 208 may be configured to move relative to device housing 188 to cause engagement member 202 to transition between the hold position and the slide position. In some examples, contact member 208 is configured to establish a holding orientation relative to device housing 188 and a sliding orientation relative to device housing 188. Contact member 208 may be configured to cause engagement member 202 to establish the hold position in the holding orientation and configured to cause engagement member 202 to establish the slide position in the sliding orientation.

[0103] In examples, catch device 186 is configured such that movement of device actuator 144 (e.g., by a clinician) causes movement of contact member 208 relative to device housing 188. Hence, catch device 186 may be configured such that, when device actuator 144 is moved (e.g., by a clinician) relative to device housing 188, contact member 208 causes engagement member 202 to transition between the hold position (FIG.6) and the slide position (FIG.7). In some examples, device actuator 144 is a portion of contact member 208.

[0104] In examples, engagement member 202 is resiliently biased to establish one of the slide position or the hold position when device housing 188 supports engagement member 202. Engagement member 202 may be resiliently biased such that, when engagement member 202 establishes a preset orientation (e.g., relative to device housing 188), a departure of engagement member 202 from the present orientation causes engagement member 202 to generate an internal stress tending to oppose the departure. Engagement member 202 may be configured such that the internal stress (e.g., in the absence of external forces acting on engagement member 202) tends to cause engagement member 202 to return to the preset orientation. For example, engagement member 202 may be configured such that the preset orientation causes engagement member 202 to establish one of the hold position or the slide position. Impartation of an external force on engagement member 202 (e.g., by contact member 208) may cause a departure from the present orientation such that, for example, engagement member establishes the other of the hold position or the slide position. Engagement member 208 may be configured such that, when the external force is removed (e.g., when contact member 208 ceases to exert theAtty Ref. No. A0012365WO01 external force), the resilient biasing causes engagement member 202 to return to the one of the hold position or the slide position.

[0105] As an example, engagement member 202 may be reliantly biased to establish the release position. Thus, in the absence of external forces acting on engagement member 202 (e.g., via contact member 208), the resilient biasing may tend to cause engagement member 202 to exert the first magnitude of force on tether body 122, such that tether body 122 may move relative to engagement member 202 (and, e.g., device housing 188). Contact member 208 may be configured to overcome the resilient biasing when contact member 208 causes engagement member 202 to transition from the release position to the hold position. Hence, in examples, catch device 186 may be a normally unlocked device which tends to allow relative motion of tether body 122 and engagement member 202 in the absence of external forces acting on engagement member 202. In some examples, when catch device 186 is a normally unlocked device, catch device 186 is configured to remain in the release configuration unless contact member 208 (e.g., via device actuator 144) acts to shift engagement member 202 from the release position to the hold position, causing catch device 186 to transition to the capture configuration.

[0106] In some examples, engagement member 202 may be reliantly biased to establish the hold position. Thus, in the absence of external forces acting on engagement member 202 (e.g., via contact member 208), the resilient biasing may tend to cause engagement member 202 to exert the second magnitude of force on tether body 122, such that movement of tether body 122 relative to engagement member 202 (and, e.g., device housing 188) is limited. Contact member 208 may be configured to overcome the resilient biasing to cause engagement member 202 to transition from the hold position to the release position. Hence, in examples, catch device 186 may be a normally locked device which tends to limit and / or substantially prevent relative motion of tether body 122 and engagement member 202 in the absence of external forces acting on engagement member 202. In some examples, when catch device 186 is a normally locked device, catch device 186 is configured to remain in the capture configuration unless contact member 208 (e.g., via device actuator 144) acts to shift engagement member 202 from the hold position to the release position, causing catch device 186 to transition to release configuration.

[0107] In examples, catch device 186 includes a compression member 209 (e.g., a spring) which tends to hold contact member 208 in a specific position relative toAtty Ref. No. A0012365WO01 engagement member 202 and / or device housing 188. The specific position of contact member 208 may cause engagement member 202 to substantially maintain one of the hold position or the slide position. In examples, compression member 209 is configured to exert a holding force HF (FIG.6) on contact member 208 to hold contact member 208 in the specific position. Catch device 186 may be configured such that holding force HF must be overcome in order to cause contact member 208 to move from the specific position. For example, catch device 186 may be configured such that a clinician must overcome holding HF to cause engagement member 202 (e.g., using device actuator 144) to transition between the release position and the hold position. In some examples, compression member 209 is configured to hold contact member 208 in a position whereby engagement member 202 substantially maintains the slide position. In some examples, compression member 209 is configured to hold contact member 208 in a position whereby engagement member 202 substantially maintains the hold position.

[0108] The catch device of medical system 100 and / or tether system 120 may include any number of engagement members. For examples, FIG.10 illustrates a plan view of a catch device 214 including a device housing 216 supporting a second engagement member 218. In FIG.10, device housing 216 is shown as a cross-section with a cutting plane parallel to the page and including longitudinal axis L. Catch device 214 is an example of catch device 140, 186, device housing 216 is an example of device housing 142, 188, and second engagement member 218 is an example of engagement member 145, 202.

[0109] In examples, second engagement member 218 is configured to limit and / or substantially prevent movement of tether body 122 in the second direction (e.g., proximal direction P) relative to second engagement member 218 (and / or device housing 216). Second engagement member 218 may be configured similarly to engagement member 202. For example, second engagement member 218 may be configured to impart a third magnitude of force (e.g., similar to or substantially equal to the first magnitude of force) to tether body 122 when second engagement member 218 is disengaged from tether body 122, and / or configured to impart a fourth level of force (e.g., similar to or substantially equal to the second level of force) to tether body 122 when second engagement member 218 is engaged with tether body 122. The fourth level of force may be greater than the second magnitude of force. Second engagement member 218 may be configured such that the fourth magnitude of force limits and / or substantially prevents movement of tether bodyAtty Ref. No. A0012365WO01 122 relative to device housing 188 in the second direction (e.g., in the proximal direction P).

[0110] Second engagement member 218 may be is configured to be disengaged from tether body 122 when second engagement member 218 is in a second member slide position relative to device housing 216, and / or configured to engage tether body 122 when second engagement member 218 is in a second member hold position relative to device housing 216. Catch device 186 may be configured to cause engagement member 202 to establish the second member slide position when catch device 186 is in the release configuration and / or be configured to cause engagement member 202 to establish the second member hold position when catch device 186 is in the capture configuration. In examples, second engagement member 218 includes a second engaging portion (not shown) configured to impart the third magnitude of force and the fourth magnitude of force on tether body 122. In examples, second engagement member 218 defines a second aperture (not shown) configured to receive tether body 122. The second engaging portion may be configured relative to second engagement member 218 in substantially the same manner as engaging portion 210 is configured relative to engagement member 202. The second aperture may be configured relative to second engagement member 218 in substantially the same manner as aperture 212 is configured relative to engagement member 202.

[0111] In examples, second engagement member 218 includes a member first end 220 attached to device housing 216 and a member second end 222 opposite member first end 220. In examples, member second end 222 is a free end of second engagement member 218. Member first end 220 may be configured (e.g., attached to device housing 216) such that member first end 220 remains substantially stationary relative to device housing 216. Member second end 222 may be configured to move relative to device housing 216 and / or member first end 220 when second engagement member 218 transitions from the second member slide position to the second member hold position.

[0112] Second engagement member 218 may be configured to exert the fourth magnitude of force (e.g., a second member force FE2) on tether body 122 in the second member hold position. Second engagement member 218 may be configured such that, when tether body 122 experiences second force F2 in the second direction (e.g., proximal direction P), second member force FE2 tends to limit motion of tether body 122 relative toAtty Ref. No. A0012365WO01 engagement member 202. For example, second engagement member 218 may be configured such that at least a component of second member force FE2 acts on tether body 122 in a direction opposite second force F2 (e.g., acts in distal direction D). Thus, when second engagement member 218 is in the second member hold position, engagement member 202 may limit movement of tether body 122 relative to second engagement member 218 and / or device housing 216 in at least the proximal direction P using second member force FE2.

[0113] In examples, second engagement member 202 may be configured to cause member force FE to have the third magnitude of force in the second member slide position and have the fourth magnitude of force in the second member hold position (e.g., configured to increase second member force FE2 in the second member hold position). In examples, second engagement member 218 is configured such that second member force FE2 (e.g., at least when second member force FE2 has the fourth magnitude of force) causes second engagement member 218 to substantially bite tether body 122 when tether body 122 attempts to move in proximal direction P relative to engagement member 202. In some examples, second engagement member 218 is resiliently biased to establish one of the second member slide position or the second member hold position when device housing 216 supports second engagement member 218.

[0114] In examples, device housing 216 supports engagement member 202 and second engagement member 218 such that the component of second member force FE acts on tether body 122 in the first direction (e.g., distal direction D) when the component of member force FE acts on tether body 122 in the second direction (e.g., proximal direction P). Hence, catch device 214 may be configured to limit movement of tether body 122 relative to device housing 216 in proximal direction P and in distal direction D such that, for example, device housing 216 remains substantially stationary relative to tether body 122. In some examples, device housing 216 supports engagement member 202 and second engagement member 218 such that second end 206 is proximal to first end 204 in at least the release position and member second end 222 is distal to member first end 220 in at least the second member release position. In some examples, engagement member 202 and second engagement member 218 substantially define a V-shape when device housing 216 supports engagement member 202 and second engagement member 218.

[0115] Catch device 214 may include a contact member 224 configured to causeAtty Ref. No. A0012365WO01 second engagement member 218 substantially maintain the second member hold position, substantially maintain the second member slide position, and / or transition between the second member hold position and the second member slide position. In examples, contact member 224 is configured to cause second engagement member 218 to substantially maintain the second member hold position while causing engagement member 202 to substantially maintain the hold position, cause second engagement member 218 to substantially maintain the second member slide position while causing engagement member 202 to substantially maintain the slide position, and / or cause second engagement member 218 to transition between the second member hold position and the second member slide position as engagement member 202 transitions between the hold position and the slide position. Contact member 224 is an example of contact member 208.

[0116] A contact member of medical system 100 and / or tether system 120 may be configured to move relative to a device housing in any manner to cause one or more engagement members to transition between a slide position and a release position. For example, as depicted in FIG 6 and FIG.7, contact member 208 may be configured to axially translate (e.g., relative to device housing 188) along a member axis MA defined by contact member 208 to cause engagement member 202 to transition between the slide position and the hold position. In examples, contact member 208 is configured such that member axis MA intersects (e.g., defines an angle with) longitudinal axis L.

[0117] In some examples, such as is illustrated in FIG.11 depicting a catch device 226, device housing 227, and contact member 228, contact member 228 is configured to rotate about member axis MA (e.g., relative to device housing 188) to cause engagement member 202 to transition between the slide position and the hold position. For example, contact member 228 may include a cammed surface 230 configured to cause engagement member to transition between the slide position and the hold position when contact member 228 rotates about member axis MA. Catch device 226 is an example of catch device 140, 186, 214. Device housing 227 is an example of device housing 142, 188, 216.

[0118] In some examples, such as is illustrated in FIG.12 depicting a catch device 232, device housing 233, and contact member 234, contact member 234 is configured to axially translate in a direction substantially parallel to longitudinal axis L (e.g., relative to device housing 188) to cause engagement member 202 to transition between the slide position and the hold position. Catch device 232 is an example of catch device 140, 186,Atty Ref. No. A0012365WO01 214, 226. Device housing 233 is an example of device housing 142, 188, 216, 227.

[0119] In some examples, such as is illustrated in FIG.13 depicting a catch device 236, device housing 237, and contact member 238, contact member 238 is configured to engage second end 206 of engagement member 202 in both the release position and the hold position. For example, contact member 238 may include an attachment portion 240 configured to be attached to second end 206. Attachment portion 240 may be configured to move relative to device housing 237 when contact member 238 moves relative to device housing 237, such that attachment portion 240 causes movement of second end 206 relative to device housing 237. The movement of second end 206 caused by attachment portion 240 may cause engagement member 202 to transition between the release configuration and the hold configuration. In some examples, device housing 237 is configured to engage attachment portion 240 to cause attachment portion 240 to keep engagement member 202 in one of the release position or the hold position. For example, device housing 237 may include a first housing feature 242 configured to mechanically mate with an attachment portion feature 244 of attachment portion 240 to keep engagement member 202 in one of the release position or the hold position. Device housing 237 may include a second housing feature 246 configured to mechanically mate with attachment portion feature 244 to keep engagement member 202 in the other of the release position or the hold position. In examples, first housing feature 242 and / or second housing feature 246 defines one of a protrusion or a recess configured to receive the protrusion, and attachment portion feature 242 defines the other the protrusion or the recess configured to receive the protrusion. Catch device 236 is an example of catch device 140, 186, 214, 226, 232. Device housing 237 is an example of device housing 142, 188, 216, 227, 233.

[0120] Contact member 208, 224, 228, 234, 238 may be configured to move in any manner relative to device housing 142, 188, 216, 229, 233, 237 to cause engagement member 202, 218 to transition between a release position and a hold position. Device actuator 144 may be configured in any manner to cause contact member 208, 228, 234 to move relative to device housing 142, 188, 216, 229, 233, 237. For example, device actuator 144 may define any element such as a button configured to move relative to (e.g., toward or away from) device housing 142, 188, 216, 229, 233, 237, a switch configured to pivot relative to device housing 142, 188, 216, 229, 233, 237, a sliding member configuredAtty Ref. No. A0012365WO01 to laterally translate (e.g., in proximal direction P and / or distal direction D) relative to device housing 142, 188, 216, 229, 233, 237, a rotating member configured to rotate relative to device housing 142, 188, 216, 229, 233, 237, or any element configured to cause contact member 208, 228, 234 to move relative to device housing 142, 188, 216, 229, 233, 237. Any of catch device 140, 186, 214, 226, 232, 236 may be a normally unlocked device or a normally unlocked device.

[0121] In some examples, an engagement member of a catch device may be configured to remain substantially stationary relative to a catch device housing. For example, the engagement member may comprise a compressive member configured to compress and exert a force on tether body 122 when the engagement member contacts tether body 122. The compressive member may be configured to generate a frictional force between the compressive member and tether body 122 which tends to keep the catch device substantially stationary relative to tether body 122. The catch device may be configured such that a clinician may overcome the frictional force, such that the clinician may causes movement of the catch device relative to tether body 122.

[0122] For example, FIG.14 illustrates a perspective view of a catch device 250 including a housing 252 (“device housing 252”). FIG.15 illustrates a perspective view of catch device 250 with device housing 252 supporting one or more engagement members. In FIG.15, device housing 252 is shown as a cross-section with a cutting plane that includes axis C-C’ of FIG.14 and a longitudinal axis L defined by device housing 252. FIG.16 illustrates a cross-sectional end view of a portion of catch device 250, with tether body 122 shown as a cross-section with a cutting plane that includes axis D-D’ of FIG.15 and a longitudinal axis L.

[0123] Device housing 252 defines device distal surface 256, device distal access 258, device proximal surface 260, device proximal access 262, depression 264, and device passage 266. Device distal surface 256 is an example of device distal surface 192, device distal access 258 is an example of device distal access163, device proximal surface 260 is an example of device proximal surface 194, device proximal access 262 is an example of device proximal access 161, depression 264 is an example of depression 196, 198, and device passage 260 is an example of device passage 160.

[0124] Catch device 250 includes one or more engagement members 267 (“engagement members 267”) such as engagement member 268. Device housing 252Atty Ref. No. A0012365WO01 supports engagement member 268. In examples, device housing 252 is configured to support engagement member 268 such that engagement member 268 remains substantially stationary relative to device housing 252. For example, device housing 252 may be configured such that, when device housing 252 moves in a direction (e.g., distal direction D or proximal direction P) relative to tether body 122, engagement member 268 moves in the direction relative to tether body 122.

[0125] Engagement members 267 is configured to exert a force on tether body 122 to oppose a movement of tether body 122 relative to device housing 252. In examples, engagement members 267 (including engagement member 268) are configured to impart a member force FF1 and / or a member force FF2 on tether body 122 to limit movement of tether body 122 relative to device housing 252. For example, when first force F1 is imparted on tether body 122 in a first direction (e.g., distal direction D), engagement members 267 may be configured to impart member force FF1 on tether body 122 in a second direction (e.g., proximal direction P) opposite the first direction. When second force F2 is imparted on tether body 122 in the second direction, engagement members 267 may be configured to impart member force FF2 on tether body 122 in the first direction.

[0126] In examples, engagement member 268 is configured to frictionally engage an outer perimeter defined by an outer surface 270 of tether body 122 (“tether outer surface 270”). Member force FF1 and / or member force FF2 may be a frictional force caused by the engagement of engagement member 268 and outer surface 270. In examples, engagement member 268 defines a boundary B1 defining a central aperture 272 configured to receive tether body 122. Boundary B1 may be configured to contact outer surface 270 when central aperture 272 receives tether body 122. In some examples, boundary B1 is configured to surround at least some portion (e.g., substantially all) of outer surface 270 when central aperture 272 receives tether body 122. Engagement member 268 may be configured such that boundary B1 frictionally engages outer surface 270 when central aperture 272 receives tether body 122. In examples, engagement member 268 is configured such that boundary B1 imparts at least some portion of member force FF1 (e.g., when force F1 is imparted on tether body 122) and / or at least some portion of member force FF2 (e.g., when force F2 is imparted on tether body) when central aperture 272 receives tether body 122.

[0127] In some examples, engagement members 267 is a plurality of engagementAtty Ref. No. A0012365WO01 members, such as engagement member 268, engagement member 274, engagement member 276, engagement member 278, engagement member 280, and engagement member 282. Engagement members 267 may include any number of engagement members. Each of engagement members 267 may be configured similarly to engagement member 268. For example, each of engagement members 267 may define a central aperture configured to receive tether body 122. Each central aperture may be configured relative to the defining engagement member in the same manner as central aperture 272 is configured relative to engagement member 268. Each engagement member may be configured such that a boundary of the each central aperture engages outer surface 270 when the each central aperture receives tether body 122. Each engagement member may be configured such that its boundary imparts at least some portion of member force FF1 and / or at least some portion of member force FF2 on tether body 122 when tether body 122 extends through each of the central apertures.

[0128] In examples, engagement members 267 are configured to collectively impart member force FF1 on tether body 122. Each of engagement members 267 may be configured to impart a portion of member force FF1, such that member force FF1 is a resultant force comprised of each of the portions of member force FF1. Engagement members 267 may be configured to collectively impart member force FF2 on tether body 122. Each of engagement members 267 may be configured to impart a portion of member force FF2, such that member force FF2 is a resultant force comprised of each of the portions of member force FF2. In examples, engagement members 267 are configured such that force FF1 has a substantially equal magnitude to force F1 (e.g., up to first force threshold), such that movement of tether body 122 relative to engagement members 267 in the first direction (e.g., distal direction D) is limited. Engagement members 267 may be are configured such that force FF2 has a substantially equal magnitude to force F2 (e.g., up to a second force threshold), such that movement of tether body 122 relative to engagement members 267 in the second direction (e.g., proximal direction P) is limited.

[0129] Catch device 250 may support engagement members 267 such that, when engagement members 267 impart member force FF1 to tether body 122, engagement members 267 transfer a force FD-1 to device housing 252. Force FD-1 may be of substantially equal magnitude and in an opposite direction to member force FF1 (e.g., of substantially equal magnitude and in the same direction as force F1). When device distalAtty Ref. No. A0012365WO01 surface 256 abuts delivery catheter proximal portion 116, device housing 252 may impart force FD-1 on delivery catheter proximal portion 116, causing delivery catheter proximal portion 116 to impart reaction force FC-1 on device housing 252. The impartation of reaction force FC-1 on device housing 252 may limit motion of device housing 252 relative to delivery catheter proximal portion 116 as member force FF1 limits motion of tether body 122 relative to engagement members 267, such that motion of tether body 122 relative to delivery catheter proximal portion 116 is limited and / or prevented. The limited motion between tether body 122 and delivery catheter proximal portion 116 may tend to limit relative motion between receptacle device 108 (e.g., supported by delivery catheter 106) and IMD 102 (e.g., when engaged with tether head 128).

[0130] In examples, engagement member 268 (and, e.g., other engagement members of engagement members 267) is configured to compress when central aperture 272 receives tether body 122. For example, engagement member 268 may be configured such that central aperture 272 defines a first cross-sectional dimension (e.g., a first diameter) in the absence of tether body 122 extending through central aperture 272 and defines a second cross-sectional dimension (e.g., a second diameter) greater than the first cross- sectional diameter when tether body 122 extends through central aperture 272. Engagement member 268 may be configured to such that tether body 122 causes engagement member to compress from defining the first cross-sectional dimension to defining the second cross-sectional dimension as a result of tether body 122 extending through central aperture 272. In examples, engagement member 268 comprises a compressible material and / or flexible configured to compress and / or deform. In examples, engagement member 268 is a compressible O-ring.

[0131] In examples, engagement member 268 (and, e.g., other engagement members of engagement members 267) is configured to impart a gripping force FG on tether body 122 when engagement member 268 is compressed by tether body 122. In examples, engagement member 268 is configured to impart gripping force FG such that gripping force FG acts from boundary B1 toward tether body 122. In examples, engagement member 268 may be configured such that a portion of gripping force FG acts through each section of boundary B1 in contact with tether body 122. Engagement member 268 may be configured to impart gripping force B1 as a resultant force comprising each of the portions of the gripping force.Atty Ref. No. A0012365WO01

[0132] In some examples, engagement member 268 is configured such that gripping force FG increases as the compression of engagement member 268 increases. For example, engagement member 268 may be configured to increase gripping force FG as the compression increases due to a Young’s modulus of a material comprising engagement member 268. Engagement member 268 may be configured to increase gripping force FG as the compression increases due to an increase in an interfacial contact area between boundary B1 and tether outer surface 270 (e.g., due to deformation of engagement member 268) as the compression increases. In examples, engagement members 267 may be configured such that the gripping force FG provided when tether body 122 extends through the central apertures of engagement members 267 limits relative motion between device housing 252 and tether body 122 at least when a handling force imparted to device housing 252 (e.g., by a clinician) is less than the first force threshold or the second force threshold. As used here, the handling force connotes a force differential between a force acting on tether body 122 and a force acting on device housing 252.

[0133] Engagement members 267 may be configured such that gripping force FG impacts the first force threshold below which engagement members 267 may produce member force FF1 having the substantially equal magnitude to force F1, and / or such that gripping force FG impacts the second force threshold below which engagement members 267 may produce member force FF2 having the substantially equal magnitude to force F2. In some examples, engagement members 267 are configured such the first force threshold and / or the second force threshold increase as gripping force FG increases. For example, member force FF1 and / or member force FF2 may be a frictional force which may be characterized by one or more coefficients of friction acting between tether outer surface 270 and each boundary (e.g., such as boundary B1) defining a central aperture of engagement members 267. Hence, engagement members 267 may be configured such that the first force threshold and the second force threshold are impacted by the coefficients of frictions and / or a magnitude of gripping force FG. In examples, engagement members 267 are configured such the first force threshold is at least greater than a magnitude of force F1 on tether body 122 anticipated to occur as medical system transits delivery catheter 106 and / or tether system 120 through vasculature and proximate to a target site.

[0134] Hence, catch device 250 is configured such that engagement members 267 limit relative motion between tether body 122 and delivery catheter 106 enroute to a targetAtty Ref. No. A0012365WO01 site to limit relative motion between receptacle device 108 and IMD 102. Catch device 250 is configured such that a clinician may apply a handling force to device housing 252 to displace catch device 250 from delivery catheter 106 (e.g., delivery catheter proximal portion 116), such that the clinician may cause the movement of IMD 102 relative to receptacle device 108 proximate a target site (e.g., for implantation of IMD 102).

[0135] FIG.17 illustrates an example tether head 128. Tether head 128 may be configured to assume an engagement configuration (e.g., to engage IMD 102 (FIG.3)) and assume a disengagement configuration to disengage from IMD 102. Tether head 128 may be configured to transition between the engagement configuration and the disengagement configuration when elongate body 180 (e.g., elongate body distal portion 182) exerts a force on tether head 128. In examples, tether handle assembly 134 is configured to cause elongate body 180 to exert the force on tether head 128 (e.g., using tether handle actuator 138). 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. In FIG.17, elongate body 180 is shown in dashed lines and extends within tether lumen 172.

[0136] In examples, tether head 128 is configured to vary and / or alter one or more dimensions of a passageway 284 into a head aperture 286 when tether head device 128 transitions between the engagement configuration and the disengagement configuration (e.g., when elongate body 180 alters the force exerted on tether head 128). In examples, head aperture 286 is configured to receive some portion of IMD 102 (e.g., a portion of an IMD retrieval structure 288 (FIG.3)). Tether head 128 may be configured to define passageway 284 leading to head aperture 286, such that the portion of IMD 102 may be received within head aperture 286 via passageway 284. Tether head 128 may be configured to vary a size of passageway 284 to engage with and / or disengage from IMD 102. For example, in an engagement configuration, tether head 128 may be configured to cause passageway 284 to be too narrow to permit the portion of IMD 102 (e.g., the portion of IMD retrieval structure 288) to pass through passageway 284, substantially preventing the portion of IMD 102 from exiting (and / or entering) head aperture 286. In a disengagement configuration, tether head 128 may be configured to cause passageway 284 to be wider than in the engagement configuration, such that the portion of IMD 102 may pass through passageway 284 to exit (and / or enter) head aperture 286. Tether handleAtty Ref. No. A0012365WO01 assembly 134 may be configured to cause tether head 128 to transition between the engagement configuration and the disengagement configuration by causing elongate body 180 to exert and / or alter the force exerted on tether head 128 by elongate body 180.

[0137] In examples, tether head 128 includes a translation member 294 configured to increase and / or decrease a size of passageway 284 and / or head aperture 286. Translation member 294 may be configured to move relative to a body 296 of tether head 128 (“tether head body 296”) to increase and / or decrease a size of passageway 284 and / or head aperture 286. For example, translation member 294 may be configured to move in the proximal direction P relative to tether head body 296 to increase a size of passageway 284 and / or head aperture 286. Translation member 294 may be configured to move in the distal direction D relative to tether head body 296 to decrease a size of passageway 284 and / or head aperture 286. In examples, tether handle assembly 134 (e.g., using tether handle actuator 138) is configured to cause translation member 294 to move relative to tether head body 296 to increase and / or decrease a size of passageway 284 and / or head aperture 286. In examples, translation member 294 and a portion of tether head body 296 define head aperture 286.

[0138] In some examples, for example when tether distal portion 124 is coupled to tether head 128, tether head body 296 is configured to remain substantially stationary relative to a portion of tether distal portion 124 when translation member 294 moves relative to tether head body 296. For example, tether head body 296 may be supported by and / or coupled to tether distal portion 124 substantially at tether distal end 125. Tether head body 296 may be configured to remain substantially stationary relative to a tether distal end 125 when translation member 294 moves relative to tether head body 296 and / or when elongate body 180 exerts and / or alters the force on tether head 128.

[0139] Tether head 128 may be configured to exert a torque on IMD 102 around a device axis LD (FIG.3) when IMD 102 (e.g., IMD retrieval structure 288) is trapped within head aperture 286. In examples, tether head 128 is configured to receive the torque from tether body 122 and transfer at least some portion of the torque to IMD 102. In examples, tether head 128 is configured to exert an axially directed force (e.g., in distal direction D or proximal direction P) on IMD 102 when IMD 102 (e.g., IMD retrieval structure 288) is trapped within head aperture 286. In examples, tether head 128 isAtty Ref. No. A0012365WO01 configured to receive the axially directed force from tether body 122 and transfer at least some portion of the axially directed force to IMD 102.

[0140] Tether head 128 and / or tether system 120 may comprise any suitable mating interface or abutment coupled to, or formed on or in tether system 120, The mating interface may be configured to mate with, receive and / or abut some portion of IMD 102 (e.g., a proximal portion of IMD 102). Tether head 128 and / or tether system 120 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 128 and / or tether system 120 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 tether system 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.

[0141] Tether head 128 may be any device configured to mate with, receive and / or abut IMD 102. In examples, tether head 128 is configured such that, when tether head 128 is engaged with IMD 102 (e.g., in the engagement configuration) and tether head 128 receives (e.g., is subjected to) a force and / or a torque, tether head 128 transfers the force and / or the torque to IMD 102. Tether head 128 may be configured such that, when tether head 128 is engaged with IMD 102 (e.g., in the engagement configuration) and IMD 102 receives (e.g., is subjected to) the force and / or the torque, IMD 102 transfers the force and / or the torque to tether head 128. In some examples, tether head 128 is configured such that, when tether head 128 is disengaged from IMD 102 (e.g., in the disengagement configuration) and tether head 128 receives (e.g., is subjected to) the force and / or the torque, tether head 128 limits the transfer of and / or fails to transfer the force and / or the torque to IMD 102. Tether head 128 may be configured such that, when tether head 128 is disengaged from IMD 102 (e.g., in the disengagement configuration) and IMD 102 receives (e.g., is subjected to) the force and / or the torque, IMD 102 limits the transfer of and / or fails to transfer the force and / or the torque to tether head 128. In some examples, tether head 128 is configured such that, when tether head 128 is engaged with IMD 102 (e.g., in the engagement configuration), an axial or rotational movement of tether head 128Atty Ref. No. A0012365WO01 causes an axial or rotational movement of IMD 102. Tether head 128 may be configured such that, when tether head 128 is disengaged from IMD 102 (e.g., in the disengagement configuration), an axial or rotational movement of tether head 128 limits and / or fails to cause an axial or rotational movement of IMD 102.

[0142] Referring largely to FIG.3, receptacle wall 110 of receptacle device 108 may include a wall body 298 defining an outer surface 302 (“wall outer surface 302”) on a first side of wall body 298 and an inner surface 304 (“wall inner surface 304”) on a second side of wall body 298 opposite the first side of wall body 298. Wall inner surface 304 may define a boundary of receptacle volume 112. Delivery catheter body 147 may define an outer surface 306 (“catheter outer surface 306”) on a first side of delivery catheter body 147 and an inner surface 308 (“catheter inner surface 308”) on a second side of delivery catheter body 147 opposite the first side of delivery catheter body 147. Catheter inner surface 308 may define a boundary of delivery lumen 118. In examples, receptacle device 108 (e.g., receptacle wall 110) is configured to define receptacle opening 109 at a distal end 111 of receptacle device 108 (“receptacle distal end 111”).

[0143] Wall outer surface 302 and at least some portion of catheter outer surface 306 are configured to be in fluidic communication with an external environment surrounding an exterior of receptacle device 108 and delivery catheter distal portion 114. For example, wall outer surface 302 and catheter outer surface 306 may be configured to be in fluid communication with a fluid environment within a chamber of heart 101 when receptacle device 108 and delivery catheter distal portion 114 are positioned (e.g., by a clinician) within heart 101. In examples, the external environment comprises a fluid (e.g., blood of a patient). A clinician may cause IMD 102 to extend from and / or distal to receptacle opening 109 using tether system 120. The clinician may cause tether head 128 to disengage from IMD 102 (e.g., using tether handle assembly 134) and proximally withdraw delivery catheter 106 and tether system 120 through delivery catheter 106. Tether body 122 may be of sufficient length such that a clinician may manipulate tether handle assembly 134 to advance tether head 128 distally through receptacle opening 109. 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 tether system 120 (e.g., tether handle assembly 134) to load IMD 102 within receptacle volume 112 via receptacle opening 109, and advance deliveryAtty Ref. No. A0012365WO01 catheter 106, with tether system 120 and IMD 102 therein, through introducer 146 and into the vasculature.

[0144] In some examples, medical system 100 (e.g., tether head 128) is configured to engage a proximal portion 310 of IMD 102 (“IMD proximal portion 310”). 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 may support IMD retrieval structure 288. IMD retrieval structure 288 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 312 (“IMD distal portion 312”) opposite IMD proximal portion 310. In examples, IMD 102 (e.g., IMD distal portion 312) 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 (e.g., defined by a housing 314 of IMD 102 (“IMD housing 314”)) causes attachment member to engage and / or disengage tissues within target site 104.

[0145] Medical system 100 (e.g., IMD 102) 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 IMD housing 314. IMD housing 314 may enclose IMD processing circuitry 133 and / or other circuitry of IMD 102. IMD housing 314 may be configured to fluidly isolate IMD processing circuitry 133 and / or other circuitry from an environment in contact with an exterior surface of IMD housing 314. In examples, IMD housing 314 is configured to hermetically seal an enclosure defined by IMD 102 and holding IMD processing circuitry 133 and / or other circuitry.

[0146] IMD housing 314 may be configured to define shapes that are easily acceptedAtty Ref. No. A0012365WO01 by the patient's body while minimizing patient discomfort. For example, IMD housing 314 may define a substantially cylindrical shape with cylindrical sidewalls. In other examples, IMD housing 314 may define substantially rectangular or other non-cylindrical shapes. IMD housing 314 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 314. In examples, IMD distal portion 312 supports attachment member 132.

[0147] Electrodes 103, 105, 107 may be configured to communicate with processing circuitry (e.g., IMD processing circuitry 133 and / or other processing circuitry). IMD processing circuitry 133 may be configured to process and / or condition a signal sensed by electrodes 103, 105, 107 and / or other electrodes within medical system 100. IMD 102 may comprise a pacemaker such as a leadless and / or wholly intracardiac pacemaker. One or more of electrodes 103, 105, 107 may be electrically connected to IMD processing circuitry 133. IMD processing circuitry 133 may be operable connected to operating circuitry configured to deliver therapy to a patient and / or sense physiological signals of the patient using electrodes 103, 105, 107.

[0148] IMD processing circuitry 133 may include fixed function circuitry and / or programmable operating circuitry. In examples, IMD processing circuitry 133 includes circuitry configured to perform one or more functions of operating circuitry, such as therapy delivery circuitry, sensing circuitry, processing circuitry, switching circuitry, communication circuitry, and / or other circuitries. IMD processing circuitry 133, as well as other processors, operating circuitry, controllers, control circuitry, and the like, described herein, may include any combination of integrated circuitry, discrete logic circuity, analog circuitry, such as one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), or field-programmable gate arrays (FPGAs). In some examples, IMD processing circuitry 133 includes multiple components, such as any combination of one or more microprocessors, one or more DSPs, one or more ASICs, or one or more FPGAs, as well as other discrete or integrated logic circuitry, and / or analog circuitry.

[0149] Functions attributed to IMD processing circuitry 133 may be embodied as software, firmware, hardware or any combination thereof. IMD processing circuitry 133 may include, for instance, a variety of capacitors, transformers, switches, and the likeAtty Ref. No. A0012365WO01 configured to perform the functions of IMD processing circuitry 133. In examples, IMD processing circuitry 133 may be configured to communicate with another device, such as a patient input / output device, a clinician input / output device, and / or others. IMD processing circuitry 133 may include any suitable hardware, firmware, software or any combination thereof for communicating with another device. In addition, IMD processing circuitry 133 may communicate with a networked computing device and a computer network. In examples, IMD processing circuitry 133 and / or other circuitry of medical system 100 is configured to deliver stimulation signals to and / or receive sensing signals from electrodes 103, 105, 107 and / or other electrodes and / or sensors within medical system 100 or external to medical system 100. IMD processing circuitry 133 may be configured to provide electrical signals, e.g., pacing therapy, to electrodes 103.105, 107 and / or other electrodes within medical system 100. IMD processing circuitry 133 may be configured to receive electrical signals, e.g., sensed cardiac electrical signals, from electrodes 103, 105, 107 and / or other electrodes within medical system 100.

[0150] Medical system 100 (e.g., processing circuitry 224) can also include memory configured to store program instructions, such as software, which may include one or more program modules, which are executable by IMD processing circuitry 133. The program instructions may be embodied in software and / or firmware. The memory can 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. In some examples, the memory includes computer-readable instructions that, when executed by IMD processing circuitry 133 cause IMD processing circuitry 133 to perform various functions described herein and / or other functions of IMD processing circuitry 133.

[0151] 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 orAtty Ref. No. A0012365WO01 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.

[0152] As used here, when a first portion of a system (e.g., medical system 100 and catch device 140, 186, 214, 226, 232, 236, 250) is substantially parallel to a second portion of or an axis defined by the system, this may mean the first portion is parallel or nearly parallel to the second portion or the axis to the extent permitted by manufacturing tolerances. In some examples, when the first portion is substantially parallel to the second portion or the axis, this may mean a first vector defined by the first component of the system defines an angle of less than 10 degrees, in some examples less than 5 degrees, and in some examples less than 1 degree, with a second vector defined by the second component or the axis. When a first portion of the system is substantially perpendicular to a second portion of or an axis defined by the system, this may mean the first portion is perpendicular or nearly perpendicular to the second portion or the axis to the extent permitted by manufacturing tolerances. In some examples, when the first portion is substantially perpendicular to the second portion or the axis, this may mean that the first vector defined by the first component of the system defines an angle of at least 80 degrees, in some examples at least 85 degrees, and in some examples at least 89 degrees, with the second vector defined by the second component. The first portion may be a first component of the system, a first axis and / or first vector defined by the first system, a first plane defined by the first system, a first area defined by the first system, and / or another portion of the first system. The second portion may be a second component of the system, a second axis and / or second vector defined by the second system, a second plane defined by the second system, a second area defined by the second system, and / or another portion of the second system.

[0153] As used here, when a first quantity is substantially equal to a second quantity, this may mean the first quantity is equal to or nearly equal to the second quantity to the extent permitted by manufacturing tolerances. In some examples, when the first quantity is substantially equal to the second quantity, this may mean a difference between the first quantity and the second quantity is less than 10% of, in some examples less than 5% of,Atty Ref. No. A0012365WO01 and in some examples less than 1% of, the first quantity or the second quantity.

[0154] A technique for limiting relative motion between an implantable medical device and a receptacle device is illustrated in FIG.18. Although the technique is described mainly with reference to medical system 100 of FIGS.1–17, the technique may be applied to other medical systems in other examples.

[0155] The technique includes imparting, using an engagement member 202, 218, 268, 274, 276, 278, 280, 282 (“engagement member 202–282”) of a catch device 140, 186, 214, 226, 232, 236, 250 (“catch device 140–250”), a force on a tether body 122 (1802). Tether body 122 may extend through a delivery lumen 118 of a delivery catheter 106. Impartation of the force on tether body 122 may cause an engagement between engagement member 202–282 and tether body 122 / In examples, tether body 122 is coupled to a tether head 128 configured to engage with and disengage from IMD 102.

[0156] The technique includes holding, using the force imparted by catch device 140– 250, a portion of tether body 122 substantially stationary with respect to a portion of delivery catheter 106 (1804). Catch device 140–250 may hold the portion of tether body 122 substantially stationary with respect to the portion of delivery catheter 106 by abutting a device housing 142, 188, 216, 227, 233, 237, 252 (“device housing 142–252” ) against delivery catheter 106. In examples, catch device 140–250 holds a portion of tether proximal portion 126 substantially stationary with respect to a portion of delivery catheter proximal portion 116. In examples, catch device 140–250 exerts the force on tether proximal portion 126.

[0157] In examples, a tether distal portion 124 is affixed to a tether head 128. In examples, tether head 128 is engaged with IMD 102. In examples, catch device 140–250 limits movement of IMD 102 relative to a receptacle device 108 of delivery catheter 106 using the force imparted on tether body 122. In examples, catch device 140–250 limits movement of IMD 102 relative to a receptacle device 108 of delivery catheter 106 by abutting device housing 142–252 against delivery catheter proximal portion 116. Catch device 140–250 may limit the movement of IMD 102 relative to a receptacle device 108 when delivery catheter 106 alters a curvature from a first curvature to a second curvature different from the first curvature. Catch device 140–250 may limits movement of IMD 102 relative to receptacle device 108 when a first portion of delivery catheter 106 defines the first curvature and a second portion of delivery catheter 106 defines the secondAtty Ref. No. A0012365WO01 curvature.

[0158] In examples, the technique includes exerting, using engagement member 202, 218 the force at a first magnitude in a hold position of engagement member 202, 218, and exerting, using engagement member 202, 218, the force at a second magnitude less than the first magnitude in a slide position of engagement member 202. In examples, engagement member 202, 218 frictionally engages tether body 122 in the hold position and displaces from tether body 122 in the slide position. In some examples, engagement member 202, 218 exerts the force at the first magnitude and the second magnitude when tether body 122 extends through an aperture 212 defined by engagement member 202. In some examples, engagement member 202 exerts the force at the first magnitude and the second magnitude using a boundary B1 of aperture 212.

[0159] In examples, engagement member 202, 218 moves relative to device housing 142, 188, 216, 227, 233, 237 (“device housing 142–237”) when engagement member 202, 218 transitions between the hold position and the slide position. A contact member 208, 224, 228, 234, 238 (“contact member 208–238”) may move relative to device housing 142–237 to cause engagement member 202, 218 to move relative to device housing 142– 237. In examples, a compression member 209 exerts a member force on contact member 208–238 limit the movement of compression member 209 relative to device housing 142– 237. Compression member 209 may limit the movement of contact member 208–238 relative to device housing 142–237 to hold engagement member 202, 218 in one of the hold position or the slide position. In examples, engagement member 202, 218 is resiliently biased to establish the hold position, such that catch device 140, 186, 214, 226, 232, 236 (“catch device 140–236”) is a normally locked device. In some examples, engagement member 202, 218 is resiliently biased to establish the slide position, such that catch device 140–236 is a normally unlocked device.

[0160] In examples, the technique includes slidably translating catch device 250 over tether body 122 when engagement member 268, 274, 276, 278, 280, 282 (“engagement member 268–282”) exerts the force on tether body 122. In examples, catch device 250 holds engagement member 268–282 substantially stationary relative to device housing 252 when catch device 250 slidably translates over tether body 122. In examples, tether body 122 extends through a plurality of central apertures (e.g., central aperture 272) defined by engagement member 268–282. Tether body 122 may compress engagement member 268–Atty Ref. No. A0012365WO01 282 when tether body extends through the plurality of central apertures. In examples, the compression of engagement member 268–282 causes engagement member 268–282 to exert the force on tether body 122.

[0161] 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. Any described structure, system, operation, or function described by a claim dependent on an independent claim may also be used and / or be present in combination with another independent claim.

[0162] Example 1: A medical system, comprising: a tether head configured to engage with and disengage from an implantable medical device; a tether including a tether body affixed to the tether head; and a catch device including a housing supporting an engagement member, wherein the engagement member is configured to exert a force on the tether body to cause an engagement between the engagement member and the tether body, wherein the housing is configured to remain substantially stationary with respect to a portion of the tether body when the engagement member exerts the force on the tether body, and wherein the housing is configured to abut a catheter proximal portion of a delivery catheter, the delivery catheter configured to hold the implantable medical device in a catheter distal portion when the engagement member exerts the force on the tether body and the housing abuts the delivery catheter proximal portion.

[0163] Example 2. The medical system of Example 1, wherein the tether body includes a tether proximal portion and a tether distal portion, wherein the tether distal portion is affixed to the tether head, wherein the engagement member is configured to exert the force on the tether proximal portion, and wherein the housing is configured to remain substantially stationary with respect to a portion of the tether proximal portion when the engagement member exerts the force on the tether proximal portion.

[0164] Example 3. The medical system of Example 1 or Example 2, further comprising the delivery catheter, wherein the delivery catheter includes a catheter body defining a catheter lumen, wherein the tether body is configured to extend within the catheter lumen, and wherein the catch device is configured to limit translation of the tether proximal portion relative to the catheter body when the housing abuts the catheter proximal portion and the engagement member exerts the force on the tether body.

[0165] Example 4. The medical system of Example 3, wherein the engagementAtty Ref. No. A0012365WO01 member is configured to limit translation of the tether proximal portion relative to the catheter body when the tether body extends within the catheter lumen, the housing abuts the catheter proximal portion, the engagement member exerts the force on the tether body, and the catheter body transitions between defining a first curvature and defining a second curvature.

[0166] Example 5. The medical system of Example 4, wherein the delivery catheter is a steerable catheter configured to define the first curvature, define the second curvature, and transition between the first curvature and the second curvature.

[0167] Example 6. The medical system of Example 4 or Example 5, wherein the engagement member is configured to limit translation of the tether head relative to the catheter body in a distal direction when the housing abuts the catheter proximal portion, the tether body extends within the catheter lumen, the engagement member exerts the force on the tether body, and the catheter body transitions between defining the first curvature and defining the second curvature.

[0168] Example 7. The medical system of any of Examples 4–6, wherein the delivery catheter is configured to alter an orientation of the catheter distal portion relative to the catheter proximal portion when the delivery catheter transitions between the first curvature and the second curvature.

[0169] Example 8. The medical system of any of Examples 4–7, further comprising the implantable medical device, the implantable medical device including an attachment member configured to engage tissue of a patient, wherein the catheter distal portion includes a receptacle device defining an receptacle volume configured to hold the implantable medical device, wherein the receptacle device defines a receptacle opening which opens into the receptacle volume, and wherein the catch device is configured to limit extension of the attachment device through the receptacle opening when delivery catheter holds the implantable medical device in the receptacle volume, the housing abuts the catheter proximal portion, the tether body extends within the catheter lumen and the engagement member exerts the force on the tether body.

[0170] Example 9. The medical system of any of Examples 1–8, wherein the catheter proximal portion includes a handle, and wherein the housing is configured to abut the handle.

[0171] Example 10. The medical system of any of Examples 1–9, wherein theAtty Ref. No. A0012365WO01 housing defines a device passage, wherein the engagement member is supported by the catch device within the device passage, and where the tether distal portion extends through the device passage.

[0172] Example 11. The medical system of Example 10, wherein the housing defines a longitudinal axis which extends through a distal access that opens into the device passage and extends through a proximal access that opens into the device passage, wherein the tether body extends through the distal access and the proximal access.

[0173] Example 12. The medical system of any of Examples 1–11, wherein the catch device is configured to slidably translate over the tether body and relative to the tether body.

[0174] Example 13. The medical system of any of Examples 1–12, further comprising a tether handle supported by the tether distal portion, wherein the tether handle is configured to cause the tether head to at least one of engage with or disengage from the implantable medical device.

[0175] Example 14. The medical system of Example 13, wherein the catch device is configured to exert the force on the tether body when the catch device is positioned between the tether handle and the tether head.

[0176] Example 15. The medical system of Example 13 or Example 14, wherein the tether handle is configured to engage a cable, wherein the cable is configured to transfer a force to the tether head to cause the tether head to at least one of engage with or disengage from the implantable medical device, and where the cable is configured to extends through a tether lumen defined by the tether body.

[0177] Example 16. The medical system of any of Examples 1–15, wherein the engagement member is configured to establish a hold position relative to the housing and a slide position relative to the housing, and wherein the engagement member is configured to exert the force at a first magnitude in the hold position and one of cease exerting the force or exert the force at a second magnitude less than the first magnitude in the slide position.

[0178] Example 17. The medical system of Example 16, wherein the engagement member is configured to frictionally engage the tether body in the hold position and displace from the tether body in the slide position.

[0179] Example 18. The medical system of Example 16 or Example 17, whereinAtty Ref. No. A0012365WO01 the engagement member includes a first end attached to the housing and a second end opposite the first end, wherein the second end is configured to move relative to the housing when the engagement member transitions from the slide position to the hold position, and wherein the first end is configured to remain substantially stationary relative to the housing when the engagement member transitions from the slide position to the hold position.

[0180] Example 19. The medical system of any of Examples 16–18, wherein the engagement member defines a boundary surrounding an aperture extending through the engagement member, wherein the tether body extends through the aperture, and wherein the engagement member is configured to cause the boundary to exert the force at the first magnitude on the tether body when the engagement member is in the hold position and cause the boundary to one of cease exerting the force or exert the force at a second magnitude less than the first magnitude when the engagement member is in the slide position.

[0181] Example 20. The medical system of Example 19, wherein the engagement member is configured to displace the boundary from the tether body in the slide position.

[0182] Example 21. The medical system of any of Examples 16–20, wherein the engagement member is biased to establish the slide position.

[0183] Example 22. The medical system of any of Examples 16–20, wherein the engagement member is biased to establish the hold position.

[0184] Example 23. The medical system of any of Examples 16–22, further comprising a contact member configured to move relative to the housing, wherein the contact member is configured to cause the engagement member to transition between the slide position and the hold position when the contact member moves relative to the housing.

[0185] Example 24. The medical system of Example 23, wherein the contact member is configured to contact the engagement member to cause the engagement member to transition between the slide position and the hold position.

[0186] Example 25. The medical system of Example 23 or Example 24, wherein the contact member is configured to exert a force on the engagement member to cause the engagement member to transition between the hold position and the slide position.

[0187] Example 26. The medical system of any of Examples 23–25, wherein theAtty Ref. No. A0012365WO01 contact member is configured to establish a holding orientation relative to the housing and a sliding orientation relative to the housing, wherein the contact member is configured to cause the engagement member to establish the hold position in the holding orientation and configured to cause the engagement member to establish the slide position in the sliding orientation.

[0188] Example 27. The medical system of any of Examples 23–26, further comprising a compression member configured to exert a member force on the contact member, wherein the contact member is configured to establish one of the holding orientation or the sliding orientation when the compression member exerts the member force.

[0189] Example 28. The medical system of any of Examples 23–27, wherein the contact member is configured to axially translate along a member axis defined by the contact member when the contact member moves relative to the housing to cause the engagement member to transition between the slide position and the hold position.

[0190] Example 29. The medical system of Example 28, wherein the contact member is configured to axially translate in a direction substantially parallel to the longitudinal axis of the housing.

[0191] Example 30. The medical system of Example 28, wherein the contact member is configured to axially translate in a direction substantially perpendicular to the longitudinal axis of the housing.

[0192] Example 31. The medical system of any of Examples 23–30, wherein the contact member is configured to rotate about the member axis when the contact member moves relative to the housing to cause the engagement member to transition between the slide position and the hold position.

[0193] Example 32. The medical system of Example 31, wherein the contact member defines a cam surface configured to cause the engagement member to transition between the slide position and the hold position when the contact member rotates about the member axis relative to the housing.

[0194] Example 33. The medical system of any of Examples 23–32, wherein the contact member extends into the device passage and includes an actuation portion outside of the device passage, and wherein the actuation portion is configured to cause the contact member to transition between the holding orientation and the sliding orientation when anAtty Ref. No. A0012365WO01 actuation force is imparted to the actuation portion.

[0195] Example 34. The medical system of Example 33, wherein the actuation portion defines a button configured to at least one of displace toward the housing or displace away from the housing to cause the contact member to transition between the holding orientation and the sliding orientation.

[0196] Example 35. The medical system of Example 33, wherein the actuation portion defines a switch configured to pivot relative to the housing to cause the contact member to transition between the holding orientation and the sliding orientation.

[0197] Example 36. The medical system of Example 33, wherein the actuation portion is configured to translate relative to the housing in the direction substantially parallel to the longitudinal axis of the housing cause the contact member to transition between the holding orientation and the sliding orientation.

[0198] Example 37. The medical system of any of Examples 1–15, wherein the catch device is configured to slidably translate over the tether body when a handling force is exerted on the housing and the engagement member exerts the force on the tether body.

[0199] Example 38. The medical system of Example 16, wherein the engagement member is configured to surround a perimeter defined by an outer surface of the tether body.

[0200] Example 39. The medical system of Example 37 or Example 38, wherein the engagement member is configured to compress when the engagement member contacts the outer surface of the tether body, wherein the engagement member is configured such that the compressions causes the engagement member to exert the force on the tether body.

[0201] Example 40. The medical system of Example 39, wherein the engagement member is configured to remain compressed when the catch device slidably translates over the tether body.

[0202] Example 41. The medical system of any of Examples 37–40, wherein the housing is configured to hold the engagement member substantially stationary relative to the housing when the catch device slidably translates over the tether body.

[0203] Example 42. The medical system of any of Examples 37–41, wherein the engagement member defines a boundary defining a central aperture, wherein the central aperture is configured to receive the tether body.

[0204] Example 43. The medical system of any of Examples 37–42, wherein theAtty Ref. No. A0012365WO01 engagement member comprises an O-ring configured to surround the tether body.

[0205] Example 44. The medical system of any of Examples 1-43 or 51, wherein the delivery catheter proximal portion comprises a proximal pusher member located at a proximal end of the delivery catheter proximal portion, the proximal pusher member being biased in the proximal direction and configured to abut the catch device and exert a proximally directed force against the catch device.

[0206] Example 45. The medical system of Example 44, wherein the proximal pusher member comprises a plunger movably received in the delivery catheter proximal portion, the plunger being spring-biased to a proximal position relative to the delivery catheter proximal portion.

[0207] Example 46. The medical system of any of Examples 44 or 45, wherein the proximal pusher member exerts the proximally directed force against the tether via the catch device.

[0208] Example 47. The medical system of any of Examples 45 or 46, wherein the delivery catheter proximal portion comprises a handle with a handle housing, and the plunger is received in the handle housing.

[0209] Example 48. The medical system of any of Examples 44-47, wherein the proximal pusher member includes a passageway, and the tether body extends through the passageway.

[0210] Example 49. The medical system of any of Examples 44-48, wherein the proximal pusher member and the catch device comprise mating features that inhibit lateral movement of the proximal pusher member and the catch device when the catch device abuts the proximal pusher member.

[0211] Example 50. The medical system of Example 50, wherein the mating features comprise a longitudinal projection located on one of the proximal pusher member and a distal end of the catch device, and a closely matching receptacle located on the other of the proximal pusher member and a distal end of the catch device.Atty Ref. No. A0012365WO01

[0212] Example 51. A medical system, comprising: a tether head configured to engage with and disengage from an implantable medical device; a tether including a tether body defining a tether proximal portion and a tether distal portion affixed to the tether head; a catch device including a housing supporting an engagement member, wherein the engagement member is configured to exert a force on the tether proximal portion to cause an engagement between the engagement member and the tether body, wherein the housing is configured to remain substantially stationary with respect to a portion of the tether proximal portion when the engagement member exerts the force on the tether body; and a delivery catheter, wherein the delivery catheter includes a catheter body defining a catheter lumen, wherein the tether body is configured to extend within the catheter lumen, wherein the housing is configured to abut a proximal portion of the delivery catheter, and wherein the delivery catheter configured to hold the implantable medical device in a distal portion of the delivery catheter when the engagement member exerts the force on the tether body and the housing abuts the proximal portion of the delivery catheter.

[0213] Example 52. The medical system of Example 51, wherein the engagement member is configured to establish a hold position relative to the housing and a slide position relative to the housing, and wherein the engagement member is configured to exert the force at a first magnitude in the hold position and one of cease exerting the force or exert the force at a second magnitude less than the first magnitude in the slide position.

[0214] Example 53. The medical system of Example 51, wherein the housing is configured to hold the engagement member substantially stationary relative to the housing when the catch device slidably translates over the tether body: wherein the engagement member is configured to compress when the engagement member contacts an outer surface of the tether body, wherein the engagement member is configured such that the compression causes the engagement member to exert the force on the tether body.Example

[0215] Example 54. A method, comprising: imparting, using an engagement member of a catch device, a force on a tether body extending through a delivery lumen of a delivery catheter to cause an engagement member to engage a tether body, wherein the tether body is coupled to a tether head configured to engage with and disengage from an implantable medical device; and holding, using the force, a portion of tether body substantially stationary with respect to a portion of the delivery catheter by abutting a housing of the catch device against the delivery catheter.Atty Ref. No. A0012365WO01

[0216] Example 55. The method of Example 54, further comprising exerting the force on a tether proximal portion of the tether body, wherein the tether body includes a tether distal portion, wherein the tether distal portion is coupled to the tether head, and wherein the housing is configured to remain substantially stationary with respect to a portion of the tether proximal portion when the engagement member exerts the force on the tether proximal portion.

[0217] Example 56. The method of Example 54 or Example 55, further comprising limiting, using the catch device, translation of the tether distal portion relative to the delivery catheter when the housing abuts a proximal portion of the delivery catheter.

[0218] Example 57. The method of Example 56, further comprising limiting, using the catch device, translation of the tether distal portion relative to the delivery catheter when the delivery catheter transitions from defining a first curvature to defining a second curvature different from the first curvature.

[0219] Example 58. The method of any of Examples 54-57, further comprising limiting, using the catch device, an extension of an attachment device of the implantable medical device through a receptacle opening of the delivery catheter.

[0220] Example 59. The method of any of Examples 54-58, further comprising slidably translating the catch device over the tether body and relative to the tether body.

[0221] Example 60. The method of any of Examples 54-59, further comprising transitioning, using a tether handle supported by the tether distal portion, the tether head between an engagement configuration wherein the tether head engages the implantable medical device and a disengagement configuration wherein the tether head disengages from the implantable medical device.

[0222] Example 61. The method of any of Examples 54-60, further comprising exerting, using the engagement member, the force at a first magnitude in a hold position of the engagement member and exerting, using the engagement member, the force at a second magnitude less than the first magnitude in a slide position of the engagement member.

[0223] Example 62. The method of Example 61, further comprising frictionally engaging the engagement member and the tether body in the hold position and displacing the engagement member from the tether body in the slide position.Atty Ref. No. A0012365WO01

[0224] Example 63. The method of Example 61 or Example 62, further comprising causing, using a contact member configured to move relative to the housing, the engagement member to move relative to the housing when the engagement member transitions from the slide position to the hold position.

[0225] Example 64. The method of Example 63, further comprising exerting, using a compression member, a member force on the contact member to hold the engagement member in one of the hold position or the slide position.

[0226] Example 65. The method of any of Examples 61-64, further comprising exerting the force on the tether body using a boundary of an aperture defined by the engagement member.

[0227] Example 66. The method of any of Examples 54-60, further comprising slidably translating, using the catch device, the engagement member over the tether body when the engagement member exerts the force on the tether body.

[0228] Example 67. The method of Example 66, further comprising compressing, using the tether body, the engagement member when the tether body extends through a central aperture defined by the engagement member.

[0229] Example 68. The method of Example 67, further comprising exerting the force when the tether body compresses the engagement member.

[0230] Example 69. The method of any of Examples 54-68, further comprising, when the catch device abuts the delivery catheter, imparting a longitudinal force tending to displace the catch device in the proximal direction relative to the delivery catheter, and / or the delivery catheter in a distal direction relative to the catch device.

[0231] Example 70. The method of Example 69, further comprising imparting the longitudinal force to the tether body via the catch device.

[0232] Example 71. The method of any of Examples 69 or 70, further comprising retaining the tether head in a proximal position relative to a portion of the delivery catheter via the longitudinal force.

Claims

Atty Ref. No. A0012365WO01 CLAIMS 1. A medical system, comprising: a tether head configured to engage with and disengage from an implantable medical device; a tether including a tether body affixed to the tether head; and a catch device including a housing supporting an engagement member, wherein the engagement member is configured to exert a force on the tether body to cause an engagement between the engagement member and the tether body, wherein the housing is configured to remain substantially stationary with respect to a portion of the tether body when the engagement member exerts the force on the tether body, and wherein the housing is configured to abut a catheter proximal portion of a delivery catheter, the delivery catheter configured to hold the implantable medical device in a catheter distal portion when the engagement member exerts the force on the tether body and the housing abuts the delivery catheter proximal portion.

2. The medical system of claim 1, wherein the tether body includes a tether proximal portion and a tether distal portion, wherein the tether distal portion is affixed to the tether head, wherein the engagement member is configured to exert the force on the tether proximal portion, and wherein the housing is configured to remain substantially stationary with respect to a portion of the tether proximal portion when the engagement member exerts the force on the tether proximal portion.

3. The medical system of claim 1 or claim 2, wherein the housing defines a device passage, wherein the engagement member is supported by the catch device within the device passage, and where the tether distal portion extends through the device passage.

4. The medical system of claim 3, wherein the housing defines a longitudinal axis which extends through a distal access that opens into the device passage and extends through a proximal access that opens into the device passage, wherein the tether body extends through the distal access and the proximal access.Atty Ref. No. A0012365WO01 5. The medical system of any of claims 1–4, wherein the catch device is configured to slidably translate over the tether body and relative to the tether body.

6. The medical system of any of claims 1–5, wherein the engagement member is configured to establish a hold position relative to the housing and a slide position relative to the housing, and wherein the engagement member is configured to exert the force at a first magnitude in the hold position and one of cease exerting the force or exert the force at a second magnitude less than the first magnitude in the slide position.

7. The medical system of claim 6, wherein the engagement member is configured to frictionally engage the tether body in the hold position and displace from the tether body in the slide position.

8. The medical system of claim 6 or claim 7, wherein the engagement member includes a first end attached to the housing and a second end opposite the first end, wherein the second end is configured to move relative to the housing when the engagement member transitions from the slide position to the hold position, and wherein the first end is configured to remain substantially stationary relative to the housing when the engagement member transitions from the slide position to the hold position.

9. The medical system of any of claims 6–9, wherein the engagement member defines a boundary surrounding an aperture extending through the engagement member, wherein the tether body extends through the aperture, and wherein the engagement member is configured to cause the boundary to exert the force at the first magnitude on the tether body when the engagement member is in the hold position and cause the boundary to one of cease exerting the force or exert the force at a second magnitude less than the first magnitude when the engagement member is in the slide position.

10. The medical system of claim 9, wherein the engagement member is configured to displace the boundary from the tether body in the slide position.Atty Ref. No. A0012365WO01 11. The medical system of any of claims 6–10, wherein the engagement member is biased to establish one of the slide position or the hold position.

12. The medical system of any of claims 6–11, further comprising a contact member configured to move relative to the housing, wherein the contact member is configured to cause the engagement member to transition between the slide position and the hold position when the contact member moves relative to the housing.

13. The medical system of claim 12, further comprising a compression member configured to exert a member force on the contact member, wherein the contact member is configured to establish one of a holding orientation or a sliding orientation when the compression member exerts the member force.

14. The medical system of any of claims 1–5, wherein the engagement member is configured to compress when the engagement member contacts an outer surface of the tether body, wherein the engagement member is configured such that the compression causes the engagement member to exert the force on the tether body.

15. The medical system of any of claims 1–5 or claim 14, wherein the housing is configured to hold the engagement member substantially stationary relative to the housing when the catch device slidably translates over the tether body.

16. The medical system of any preceding claim, wherein the delivery catheter proximal portion comprises a proximal pusher member located at a proximal end of the delivery catheter proximal portion, the proximal pusher member being biased in the proximal direction and configured to abut the catch device and exert a proximally directed force against the catch device.

17. The medical system of claim 16, wherein the proximal pusher member comprises a plunger movably received in the delivery catheter proximal portion, the plunger being spring-biased to a proximal position relative to the delivery catheter proximal portion.Atty Ref. No. A0012365WO01 18. The medical system of claim 16 or claim 17, wherein the proximal pusher member exerts the proximally directed force against the tether via the catch device.

19. The medical system of claim 17 or claim 18, wherein the delivery catheter proximal portion comprises a handle with a handle housing, and the plunger is received in the handle housing.

20. The medical system of any of claims 16-19, wherein the proximal pusher member includes a passageway, and the tether body extends through the passageway.

21. The medical system of any of claims 16-20, wherein the proximal pusher member and the catch device comprise mating features that inhibit lateral movement of the proximal pusher member and the catch device when the catch device abuts the proximal pusher member.

22. The medical system of claim 21, wherein the mating features comprise a longitudinal projection located on one of the proximal pusher member and a distal end of the catch device, and a closely matching receptacle located on the other of the proximal pusher member and a distal end of the catch device.

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