Abstract: Implementations described and claimed herein provide systems and methods for delivering and retrieving a leadless pacemaker. In one implementation, a leadless pacemaker has a docking end, and the docking end having a docking projection extending from a surface. A docking cap has a body defining a chamber. The docking cap has a proximal opening into the chamber. The proximal opening is coaxial with a longitudinal axis of a lumen of a catheter. A retriever has a flexible grasper with a first arm disposed opposite a second arm. Each of the first arm and the second arm form a hinge biased radially outwards from the longitudinal axis. The docking cap locks the first arm and the second arm on the docking projection when the body is sheathed over the retriever until the flexible grasper is disposed within the chamber.

Abstract: A biostimulator, such as a leadless cardiac pacemaker, including a fixation element to engage tissue and one or more backstop elements to resist back-out from the tissue, is described. The fixation element can be mounted on a housing of the biostimulator such that a helix of the fixation element extends distally to a leading point. The leading point can be located on a distal face of the helix at a position that is proximal from a center of the distal face. The backstop elements can include non-metallic filaments, such as sutures, or can include a pinch point of the biostimulator. The backstop features can grip the tissue to prevent unscrewing of the fixation element. Other embodiments are also described and claimed.

Abstract: In at least one embodiment, a system and method for implanting an implantable medical device (IMD) within a patient may include an IMD including a housing and an attachment member, and a delivery catheter including a tethering snare that is configured to be selectively extended out of the delivery catheter and retracted into the delivery catheter. In at least one embodiment, a system and method for implanting an implantable medical device (IMD) within a patient may include an IMD including a housing and an attachment member, wherein the attachment member includes a central passage connected to a connection chamber, and a delivery catheter including first and second tethers that may be moved outwardly from and retracted into the delivery catheter.

Abstract: A biostimulator, such as a leadless cardiac pacemaker, including a fixation element to engage tissue and one or more backstop elements to resist back-out from the tissue, is described. The fixation element can be mounted on a housing of the biostimulator such that a helix of the fixation element extends distally to a leading point. The leading point can be located on a distal face of the helix at a position that is proximal from a center of the distal face. The backstop elements can include non-metallic filaments, such as sutures, or can include a pinch point of the biostimulator. The backstop features can grip the tissue to prevent unscrewing of the fixation element. Other embodiments are also described and claimed.

Abstract: In at least one embodiment, a system and method for implanting an implantable medical device (IMD) within a patient may include an IMD including a housing and an attachment member, and a delivery catheter including a tethering snare that is configured to be selectively extended out of the delivery catheter and retracted into the delivery catheter. In at least one embodiment, a system and method for implanting an implantable medical device (IMD) within a patient may include an IMD including a housing and an attachment member, wherein the attachment member includes a central passage connected to a connection chamber, and a delivery catheter including first and second tethers that may be moved outwardly from and retracted into the delivery catheter.

Abstract: A biostimulator transport system, such as a biostimulator delivery system, having a swaged torque shaft, is described. The torque shaft includes an outer cable coaxially arranged with an inner coil. The inner coil has a single wire coil extending around a central axis in a first helical direction, and the outer cable has several outer strands that extend around the central axis in a second helical direction that is different than the first helical direction. The outer cable can be swaged to form a close fit to the inner coil. The close fit of the swaged coaxial torque shaft structure can track to a target site through tortuous vessels and efficiently transfer torque from a handle to a docking cap of the biostimulator transport system to drive a biostimulator into the target site. Other embodiments are also described and claimed.

Abstract: Disclosed herein is a delivery catheter for implanting a leadless biostimulator. The delivery catheter includes a shaft and a tubular body having a lumen and an atraumatic end. The atraumatic end includes at least one of a braided, woven or mesh construction configured to facilitate the atraumatic end changing diameter. When a distal portion of the shaft is coupled to a proximal region of the leadless biostimulator, at least one of distally displacing the tubular body relative to the shaft or proximally displacing the shaft relative to the tubular body causes the leadless biostimulator to be received in the volume of the atraumatic end and the atraumatic end to encompass the leadless biostimulator. Conversely, at least one of proximally displacing the tubular body relative to the shaft or distally displacing the shaft relative to the tubular body causes the leadless biostimulator to exit the volume of the atraumatic end.

Abstract: A medical tool includes a rotation mechanism that further includes a warning feature. The warning feature provides an indication when the rotation mechanism has achieved a number of rotations.

Abstract: A biostimulator, such as a leadless cardiac pacemaker, including coaxial fixation elements to engage or electrically stimulate tissue, is described. The coaxial fixation elements include an outer fixation element extending along a longitudinal axis and an inner fixation element radially inward from the outer fixation element. One or more of the fixation elements are helical fixation elements that can be screwed into tissue. The outer fixation element has a distal tip that is distal to a distal tip of the inner fixation element, and an axial stiffness of the outer fixation element is lower than an axial stiffness of the inner fixation element. The relative stiffnesses are based on one or more of material or geometric characteristics of the respective fixation elements. Other embodiments are also described and claimed.

Abstract: Disclosed herein is a delivery catheter for implanting a leadless biostimulator. The delivery catheter includes a shaft and a tubular body having a lumen and an atraumatic end. The atraumatic end includes at least one of a braided, woven or mesh construction configured to facilitate the atraumatic end changing diameter. When a distal portion of the shaft is coupled to a proximal region of the leadless biostimulator, at least one of distally displacing the tubular body relative to the shaft or proximally displacing the shaft relative to the tubular body causes the leadless biostimulator to be received in the volume of the atraumatic end and the atraumatic end to encompass the leadless biostimulator. Conversely, at least one of proximally displacing the tubular body relative to the shaft or distally displacing the shaft relative to the tubular body causes the leadless biostimulator to exit the volume of the atraumatic end.

Abstract: A biostimulator transport system, such as a biostimulator delivery system, having a swaged torque shaft, is described. The torque shaft includes an outer cable coaxially arranged with an inner coil. The inner coil has a single wire coil extending around a central axis in a first helical direction, and the outer cable has several outer strands that extend around the central axis in a second helical direction that is different than the first helical direction. The outer cable can be swaged to form a close fit to the inner coil. The close fit of the swaged coaxial torque shaft structure can track to a target site through tortuous vessels and efficiently transfer torque from a handle to a docking cap of the biostimulator transport system to drive a biostimulator into the target site. Other embodiments are also described and claimed.

Abstract: A medical tool includes a rotation mechanism that further includes a warning feature. The warning feature provides an indication when the rotation mechanism has achieved a number of rotations.

Abstract: A device for loading a leadless pacemaker onto a catheter-based delivery system includes a distal portion and a proximal portion. The distal portion includes a retention feature configured to receive the leadless pacemaker. The proximal portion is proximal the distal portion and includes a funneling structure opening toward the retention feature. The distal and proximal portions of the device are configured such that, when a distal end of the catheter-based delivery system is brought towards the proximal portion of the loading device and the leadless pacemaker is retained by the retention feature, the funneling structure guides features of the distal end of the catheter-based delivery system through an opening in an attachment feature located at a proximal end of the leadless pacemaker.

Abstract: A biostimulator, such as a leadless cardiac pacemaker, including coaxial fixation elements to engage or electrically stimulate tissue, is described. The coaxial fixation elements include an outer fixation element extending along a longitudinal axis and an inner fixation element radially inward from the outer fixation element. One or more of the fixation elements are helical fixation elements that can be screwed into tissue. The outer fixation element has a distal tip that is distal to a distal tip of the inner fixation element, and an axial stiffness of the outer fixation element is lower than an axial stiffness of the inner fixation element. The relative stiffnesses are based on one or more of material or geometric characteristics of the respective fixation elements. Other embodiments are also described and claimed.

Abstract: A leadless biostimulator includes a housing, and distal and proximal electrodes disposed on or integrated into the housing. The distal electrode includes an electrode body and an electrode tip mounted on a distal end of the electrode body, wherein the electrode tip is electrically conductive and configured to be placed in contact with a stimulation site. The electrode tip includes a distal tip end facing a surrounding environment and opposite a proximal tip end. The electrode tip defines a tip hole extending through the electrode tip along a longitudinal axis of the housing from the distal tip end to the proximal tip end. The tip hole comprises a through hole having a first diameter at the distal tip end and a second diameter at the proximal tip end of the tip electrode, wherein the first diameter of the tip hole is less than the second diameter of the tip hole.

Abstract: A leadless biostimulator including an attachment feature to facilitate precise manipulation during delivery or retrieval is described. The attachment feature can be monolithically formed from a rigid material, and includes a base, a button, and a stem interconnecting the base to the button. The stem is a single post having a transverse profile extending around a central axis. The transverse profile can be annular and can surround the central axis. The leadless biostimulator includes a battery assembly having a cell can that includes an end boss. A tether recess in the end boss is axially aligned with a face port in the button to receive tethers of a delivery or retrieval system through an inner lumen of the stem. The attachment feature can be mounted on and welded to the cell can at a thickened transition region around the end boss. Other embodiments are also described and claimed.

Abstract: A loading tool for loading a biostimulator onto a biostimulator delivery system is described. The loading tool includes a first body portion and a second body portion connected by a hinge. A latch is mounted on the first body portion, and the latch can be locked to fasten the first body portion to the second body portion. A biostimulator can be mounted in the loading tool, and a tether of a biostimulator delivery system can be inserted through a funnel in the loading tool to engage the biostimulator. An operator can use only one hand to unlock the latch, open the loading tool, and remove the loading tool from the biostimulator prior to delivering the biostimulator into a patient. Other embodiments are also described and claimed.

Abstract: A device for loading a leadless pacemaker onto a catheter-based delivery system includes a distal portion and a proximal portion. The distal portion includes a retention feature configured to receive the leadless pacemaker. The proximal portion is proximal the distal portion and includes a funneling structure opening toward the retention feature. The distal and proximal portions of the device are configured such that, when a distal end of the catheter-based delivery system is brought towards the proximal portion of the loading device and the leadless pacemaker is retained by the retention feature, the funneling structure guides features of the distal end of the catheter-based delivery system through an opening in an attachment feature located at a proximal end of the leadless pacemaker.

Abstract: Implementations described and claimed herein provide systems and methods for delivering and retrieving a leadless pacemaker. In one implementation, a leadless pacemaker has a docking end, and the docking end has a docking projection extending from a surface. A docking cap has a body defining a chamber. A retriever has sheaths extending with lumens distally from the chamber. A snare extends between the lumens forming a first snare loop pointing in a first direction and a second snare loop pointing in a second direction with a docking space formed therebetween. The snare is movable between an engaged position and a disengaged position by translating the first snare wire and the second snare wire within the first snare lumen and the second snare lumen. The engaged position includes the first snare wire and the second snare wire tightened around the docking projection within the docking space.

Abstract: A leadless biostimulator has a housing including an electronics compartment, an electronics assembly mounted in the electronics compartment, a proximal electrode that disposed on and/or integrated into the housing, and an electrical feedthrough assembly. The electrical feedthrough assembly includes a distal electrode and a flange. The flange is mounted on the housing. The distal electrode is electrically isolated from the flange by an insulator and configured to be placed in contact with target tissue to which a pacing impulse is to be transmitted by the leadless biostimulator. A mount is mounted on the flange and thereby mounted on the electrical feedthrough assembly. A fixation element is mounted on the mount and configured to facilitate fixation of the leadless biostimulator to tissue of a patient.