CN118574582A - Tunneling and insertion tool for implantable medical devices - Google Patents

Abstract

A tool includes a handle, a plunger actuator proximate the handle (42), a shaft (44) extending from the handle, a plunger (52), and an engagement mechanism. The shaft includes a proximal end and a distal end, and the shaft defines a channel extending along a length of the shaft. First actuation of the plunger actuator translates the plunger in a distal direction along the length of the shaft. A second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft. The engagement mechanism is disposed on the distal end and configured to engage an implantable medical device (16), and release the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in the distal direction along a length of the shaft.

Description

Tunneling and insertion tool for implantable medical devices

Technical Field

The present disclosure relates to medical devices, and more particularly to medical devices for tunneling and inserting implantable medical devices within a patient.

Background

An Implantable Medical Device (IMD), such as, for example, a cardiac pacemaker, includes a lead having a lead body including one or more elongate electrical conductors. Electrical conductors extend through the lead body from a connector assembly disposed at a first lead end proximal to the housing of the associated IMD to one or more electrodes located at a distal lead end or elsewhere along the length of the lead body. Conductors connect stimulation and/or sensing circuitry within the IMD housing to respective electrodes or sensors. Each electrical conductor is typically electrically insulated from the other electrical conductors and encased within an outer sheath that electrically insulates the lead conductors from body tissue and fluids.

Therapeutic electrical stimulation provided by leads connected to the IMD may include signals such as pulses or shocks for pacing, cardioversion, or defibrillation. In some cases, the medical device may sense intrinsic depolarizations of the heart and control delivery of the stimulation signal based on the sensed depolarizations. IMDs may also be used to perform temporary cardiac pacing after the end of a surgical procedure, or may be implanted on a temporary basis (e.g., up to about 90 days) to provide pacing support to patients who may have temporary conduction disturbances, or as a bridge between permanent implants in the event of device or system infection. In some examples, the conduction disorder treatable using the temporary IMD may be the result of Transcatheter Aortic Valve Replacement (TAVR), or may be caused by alcohol-space ablation or lyme cardiotis, or the like.

Disclosure of Invention

In general, the present disclosure relates to tools and techniques for tunneling within a patient (such as subcutaneously) with such tools, e.g., to facilitate implantation of an Implantable Medical Device (IMD) or component thereof into a space created by the tunneling. Example tools may include one or more features that provide advantages, e.g., ease of delivery and implantation of an IMD during such procedures. For example, the tool may be configured to act as both a tunneling tool and a delivery tool for delivering IMDs. Further, the tool may include an engagement mechanism disposed at a distal end of the shaft of the tool. The engagement mechanism may be configured to engage the IMD and release the IMD in response to a contact force exerted by the plunger on the IMD exceeding a reaction force of the engagement mechanism.

The engagement mechanism may engage an engagement feature of the IMD. For example, the engagement mechanism may include a first protrusion and a second protrusion, and the engagement feature may include a first surface of the IMD defining a first recess configured to receive the first protrusion and a second surface of the IMD defining a second recess configured to receive the second protrusion. The engagement mechanism may prevent movement of the IMD when the first and second protrusions are inserted into the first and second recesses, respectively, such as when the IMD is advanced subcutaneously. In this way, the tool may facilitate delivery of the IMD when at least a portion of the IMD is disposed outside of the channel of the shaft of the tool, which may advantageously improve handling and fixation of the IMD during the implantation procedure.

In some examples, a tool includes: a handle; a plunger actuator proximate to the handle; a shaft extending from the handle, wherein the shaft includes a proximal end and a distal end, and wherein the shaft defines a channel extending along a length of the shaft; a plunger disposed at least partially within the channel, wherein a first actuation of the plunger actuator translates the plunger in a distal direction along a length of the shaft, and wherein a second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft; and an engagement mechanism disposed on the distal end, wherein the engagement mechanism is configured to: engaging the implantable medical device, and releasing the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in a distal direction along a length of the shaft.

In some examples, a system includes: an implantable medical device comprising an engagement feature; and a tool, the tool comprising: a handle; a plunger actuator proximate to the handle; a shaft extending from the handle, wherein the shaft includes a proximal end and a distal end, and wherein the shaft defines a channel extending along a length of the shaft; a plunger disposed at least partially within the channel, wherein a first actuation of the plunger actuator translates the plunger in a distal direction along a length of the shaft, and wherein a second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft; and an engagement mechanism disposed on the distal end, wherein the engagement mechanism is configured to: engaging an engagement feature of the implantable medical device, and releasing the engagement feature of the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in a distal direction along a length of the shaft.

In some examples, a method includes: translating a plunger in a distal direction along a length of a shaft of the tool in response to a first actuation of a plunger actuator of the tool to form a tunnel in a body of a patient; translating the plunger in a proximal direction along the length of the shaft in response to a second actuation of the plunger actuator; engaging the implantable medical device via an engagement mechanism of the tool; and releasing the implantable medical device in response to the plunger exerting a contact force on the implantable medical device that exceeds a reaction force of the engagement mechanism as the plunger translates in the distal direction along the length of the shaft.

This summary is intended to provide an overview of the subject matter described in this disclosure. It is not intended to provide an exclusive or exhaustive explanation of the systems, devices, and methods described in detail in the drawings and the following description. Further 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 statements provided below.

Drawings

The following drawings are illustrative of example embodiments and do not limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in connection with the explanations in the following detailed description. Examples will be described below in conjunction with the accompanying drawings, in which like reference numerals refer to like elements.

Fig. 1 is a conceptual diagram illustrating an example system including an implantable medical device coupled to an implantable medical lead.

Fig. 2 is a conceptual diagram illustrating an example tunneling and implantation tool.

Fig. 3A is a conceptual diagram illustrating an example tunneling and insertion tool with a distal end of a plunger of the tool disposed beyond a distal end of a shaft of the tool.

Fig. 3B is a conceptual diagram illustrating an example tunneling and insertion tool with a distal end of a plunger of the tool disposed within a shaft of the tool.

Fig. 4A-4C are conceptual diagrams illustrating an example system including a tunneling and insertion tool and an implantable medical device.

Fig. 5 is a flow chart illustrating an example technique for operating an example tunneling and insertion tool.

Detailed Description

Fig. 1 is a conceptual diagram illustrating a portion of an example implantable medical device system 10 ("system 10") according to one or more aspects of the present disclosure. The system 10 may be used as a single-chamber (e.g., ventricular) pacemaker, as shown in the example of fig. 1, or as a dual-chamber pacemaker that delivers pacing to the heart 12 of the patient 14.

In the example of fig. 1, system 10 includes an Implantable Medical Device (IMD) 16.IMD 16 may be configured to be coupled to an implantable medical lead 18 ("lead 18"). The lead 18 may include an elongate lead body 20 having a distal portion 22. The distal portion 22 of the lead 18 is positioned at a target site 24 within the heart 12 of the patient 14. The distal portion 22 may include one or more electrodes. The target site 24 may be located at a ventricular wall of the heart 12. The leads 18 may be bipolar leads or multipolar leads.

The clinician may maneuver the distal portion 22 through the vasculature of the patient 14 to position the distal portion 22 at or near the target site 24. For example, the clinician may direct the distal portion 22 through the Superior Vena Cava (SVC) to a target site 24 on or within the ventricular wall of the heart 12, e.g., at the apex of the right ventricle as shown in FIG. 1. In some examples, other approaches or techniques may be used to guide the distal portion 22 into other target implantation sites within the body of the patient 14. The system 10 may include a delivery catheter and/or an external member (not shown), and the lead 18 may be guided and/or maneuvered within the lumen of the delivery catheter to access the target site 24.

Lead 18 may include electrodes 26A and 26B (collectively, "electrodes 26") configured to be positioned on, within, or near cardiac tissue at or near target site 24. In some examples, electrode 26 is configured to function as an electrode, for example, to provide pacing to heart 12. The electrode 26 may be electrically connected to a conductor (not shown) extending through the lead body 20. In some examples, the conductors are electrically connected to therapy delivery circuitry of IMD 16, wherein the therapy delivery circuitry is configured to provide electrical signals to electrodes 26 via the conductors. The electrodes 26 may conduct electrical signals to target tissue of the heart 12, thereby depolarizing the myocardium, e.g., a ventricle, and contracting at regular intervals. Electrode 26 may also be connected to sensing circuitry of IMD 16 via conductors, and the sensing circuitry may sense activity of heart 12 via electrode 26. The electrode 26 may have various shapes such as teeth, spirals, screws, rings, etc. Again, although a bipolar configuration of leads 18 including two electrodes 26 is shown in fig. 1, in other examples, IMD 16 may be coupled to leads including a different number of electrodes (such as one electrode, three electrodes, or four electrodes).

In one or more examples, IMD 16 includes electronic circuitry contained within a polymer and/or metal housing, where the circuitry may be configured to deliver cardiac pacing. In the example of fig. 1, electronic circuitry within IMD 16 may include therapy delivery circuitry electrically coupled to electrode 26. The electronic circuitry within IMD 16 may also include sensing circuitry configured to sense electrical activity of heart 12 via electrodes 26. The therapy delivery circuitry may be configured to administer cardiac pacing via electrodes 26, for example, by delivering pacing pulses in response to expiration of a timer and/or in response to detection of activity (or absence thereof) of the heart.

Fig. 2 is a conceptual diagram of an example tunneling and insertion tool 40 ("tool 40"). The system 10 may include a tool 40. In accordance with the techniques of this disclosure, tool 40 is configured to generate a tunnel in which IMD 16 is positioned. In other words, tool 40 may be used to tunnel tissue (e.g., subcutaneous tissue) to create a path and/or space within the tissue. Tool 40 is also configured to insert IMD 16 into the space. IMD 16 may be a cardiac device such as a pacemaker.

As shown in fig. 2, tool 40 includes a handle 42. Shaft 44 may extend from handle 42. Shaft 44 may include a proximal end 46 and a distal end 48. Shaft 44 may define a channel 50. The channel 50 may extend from the proximal end 46 to the distal end 48. In some examples, shaft 44 may be about 3.5 inches long. However, other lengths of shaft 44 are also contemplated by the present disclosure. For example, the length of shaft 44 may be in the range of about 2 inches to 6 inches.

The plunger 52 may be at least partially disposed within the channel 50. The plunger 52 may be an elongated member that is operably coupled to a plunger actuator 54 proximate the handle 42. Actuation of the plunger actuator 54 may cause the plunger 52 to translate along the length of the shaft 44, as discussed in more detail below. In some examples, the plunger actuator 54 may be a lever, dial, button, switch, or any other actuator known in the art for controlling translation of the plunger 52. In some examples, the plunger 52 may be about 4 inches long. However, other lengths of the plunger 52 are also contemplated by the present disclosure. For example, the length of the plunger 52 may be in the range of about 2 inches to 8 inches.

First actuation of plunger actuator 54 (schematically represented by arrow 56) may cause plunger 52 to translate in a distal direction along the length of shaft 44. First actuation of the plunger actuator 54 may cause the plunger actuator 54 to transition from a first position (as shown in fig. 3A) to a second position (as shown in fig. 3B). A second actuation of plunger actuator 54 (schematically represented by arrow 58) may cause plunger 52 to translate in a proximal direction along the length of shaft 44. A second actuation of the plunger actuator 54 may cause the plunger actuator 54 to transition from the second position to the first position.

In some examples, the first actuation may correspond to moving the plunger actuator 54 in a generally proximal direction and the second actuation may correspond to moving the plunger actuator 54 in a generally distal direction. As discussed in more detail below, this configuration may advantageously reduce the likelihood of accidental release of IMD 16 when an operator of tool 40 inserts IMD 16. However, it should be understood that other configurations for actuating the plunger actuator 54 are also contemplated by the present disclosure. Further, the appropriate configuration for actuating the plunger actuator 54 may vary based on the type of plunger actuator 54 (e.g., lever, dial, button, switch, etc.) of the tool 40.

The distal end 60 of the plunger 52 is configured to tunnel into tissue to form a passageway for advancing the IMD 16. For example, in response to a first actuation of the plunger actuator 54, the distal end 60 may be disposed beyond the distal end 48 of the shaft 44 such that the distal end 60 contacts the patient's body. For example, moving the plunger actuator 54 in a generally proximal direction causes the plunger 52 to translate in a distal direction along the length of the shaft 44 such that the distal end 60 of the plunger 52 is disposed beyond the distal end 48 of the shaft 44. In some examples, the distal end 60 may be disposed about 0.25 inches beyond the distal end 48. However, the distal end 60 may be disposed beyond the distal end 48 by other lengths. For example, the distal end 60 may be disposed about 0.1 inch to 2 inches beyond the distal end 48. In some examples, the distal end 60 may be generally spherical and define a blunt tip. In other examples, the distal end 60 may be configured to facilitate dissection (e.g., the distal end 60 may define a sharp tip).

Tool 40 may include an engagement mechanism 62 configured to engage IMD 16. For example, shaft 44 may define a first projection 64A and a second projection 64B (collectively, "projections 64") at distal end 48, and engagement mechanism 62 may include projections 64. Shaft 44 may define a gap "G" between protrusions 64, and protrusions 64 may engage IMD 16 when IMD 16 is positioned in G (i.e., between protrusions 64). For example, the protrusions 64 (and at least a portion of the shaft 44) may be formed from an elastic material (e.g., acrylonitrile Butadiene Styrene (ABS), polycarbonate, polyaryletheretherketone (PEEK) thermoplastic polymer, etc.) that is biased to maintain the size of G between the protrusions 64. IMD 16 may have one or more dimensions that are larger than IMD 16; however, due to the flexibility of projections 64, an operator may press IMD 16 between projections 64. In some examples, IMD 16 may define engagement features discussed in more detail below to allow protrusions 64 to "snap" onto IMD 16 in such a way as to ensure reliable engagement of IMD 16.

Engagement mechanism 62 may also be configured to release IMD 16. For example, as plunger 52 translates in a distal direction along the length of shaft 44, engagement mechanism 62 may release IMD 16 in response to a contact force exerted by plunger 52 on IMD 16 exceeding a reaction force of engagement mechanism 62 (e.g., a bias of protrusions 64 to maintain the size of G between protrusions 64). As plunger 52 translates in a distal direction along the length of shaft 44 and then contacts at least a portion of IMD 16, plunger 52 may exert a contact force on IMD 16. As such, plunger 52 may exert a contact force on IMD 16 in response to a first actuation of plunger actuator 54.

In some examples, tool 40 includes lock actuator 66. The lock actuator 66 may be proximate to the handle 42. The lock actuator 66 may be configured to prevent translation of the plunger 52 along the length of the shaft 44. For example, a first actuation of lock actuator 66 may cause a lock of tool 40 (see fig. 3A) to engage, thereby preventing translation of plunger 52 in a proximal direction along the length of shaft 44. The second actuation of lock actuator 66 causes the lock of tool 40 to disengage, thereby enabling translation of plunger 52 in a proximal direction along the length of shaft 44.

Fig. 3A is a conceptual diagram of tool 40 with distal end 60 of plunger 52 disposed beyond distal end 48 of shaft 44. As shown in fig. 3A, a portion of the housing of tool 40 is removed to show the internal components of tool 40. As further shown in fig. 3A, the plunger actuator 54 is in the first position.

As described above, the plunger actuator 54 is operatively coupled to the plunger 52. For example, the plunger actuator 54 may extend from or otherwise be connected to the cam 68. Cam 68 may be a rotating member that rotates about pivot 70. In some examples, cam 68 may surround pivot 70. In any event, when the operator actuates the plunger actuator 54, the cam 58 may correspondingly rotate in accordance with the movement of the plunger actuator 54. For example, when the tool 40 is oriented in the manner shown in fig. 3A, the cam 58 may be rotated corresponding to a first actuation of the plunger actuator 54 by rotating in a clockwise direction, and the cam 58 may be rotated corresponding to a second actuation of the plunger actuator 54 by rotating in a counter-clockwise direction.

Cam 58 may be operably coupled to a proximal end 72 of plunger 52. For example, as shown in fig. 3A, a portion 74 of the cam 58 may be in contact with the proximal end 72. As such, when the cam 58 is rotated in a clockwise direction (e.g., in response to a first actuation of the plunger actuator 54), the portion 74 may exert a force on the plunger 52 and cause the plunger 52 to translate in a distal direction along the length of the shaft 44. In some examples, the plunger 52 may be coupled to a spring 76 (i.e., the plunger 52 may be spring loaded). The spring 76 may be configured to prevent translation of the plunger 52 in a distal direction along the length of the shaft 44 by exerting a proximal force on the plunger 52. Thus, in these examples, when the force exerted by portion 74 on plunger 52 is greater than the force exerted by spring 76 on plunger 52, plunger 52 may translate in a distal direction along the length of shaft 44. Further, when the force exerted by portion 74 on plunger 52 is less than the force exerted by spring 76 on plunger 52, plunger 52 may translate in a proximal direction along the length of shaft 44.

As described above, lock 78 may be configured to prevent translation of plunger 52 in a proximal direction along the length of shaft 44. For example, as shown in FIG. 3A, the lock actuator 66 may extend from a surface of the lock 78. In response to a first actuation of the lock actuator 66, the lock 78 may be engaged by movement in a generally distal direction to prevent rotation of the cam 58. When the lock 78 is engaged, the distal end 80 may protrude distally such that at some point during counterclockwise rotation of the cam 58, a feature 82 (e.g., a protrusion) of the cam 68 contacts and is blocked by the distal end 80. Contact between distal end 80 and feature 82 may prevent further counterclockwise rotation of cam 58, which in turn may prevent translation of plunger 52 in the proximal direction along the length of shaft 44. Conversely, the lock 78 may be disengaged by moving in a generally proximal direction such that the distal end 80 no longer blocks rotation of the cam 85.

In some examples, lock 78 is spring loaded. For example, the proximal end 84 of the lock 78 may be coupled to a spring 86. In such an example, the second actuation of the lock actuator 66 may compress the spring 86. As shown in fig. 3B, the feature 82 may prevent the distal end from protruding distally, in this way preventing expansion of the (compressed) spring 86 and causing the lock 78 to be spring loaded. In response to the first actuation of the plunger actuator 52, the feature 82 may no longer block the distal end 80 from distally protruding, causing the spring 86 to expand and the distal end 80 to distally protrude, effectively performing the first actuation of the lock actuator 66. Automatically performing the first actuation of the lock actuator in this manner may be advantageous by saving operator time, which may be particularly valuable in a medical environment.

Fig. 3B is a conceptual diagram of tool 40 with the entire plunger 52 (including distal end 60 of plunger 52) disposed within shaft 44. As shown in fig. 3B, a portion of the housing of tool 40 is removed to show the internal components of tool 40. As further shown in fig. 3B, the plunger actuator 54 is in the second position.

When the plunger actuator 54 is in the first position shown in the example of fig. 3A, the distal end 60 may be disposed beyond the distal end 48. When the plunger actuator 54 is in the second position shown in the example of fig. 3B, the distal end 60 may be disposed within the shaft 44. When the plunger actuator 54 is in the first position, the operator may engage the lock 78 in such a way as to prevent translation of the plunger 52 in a proximal direction along the length of the shaft 44. When the plunger actuator 52 is in the second position, the operator may not be able to engage the lock 78 because, as shown in the example of fig. 3B, the feature 82 may prevent the distal end 80 from protruding distally. In some examples, when lock 78 is not engaged (and when the operator is not manipulating plunger actuator 54), spring 76 may exert a proximal force on plunger 52 to rotate cam 68 counterclockwise such that plunger actuator 54 is biased to assume the second position.

In some examples, shaft 44 may not surround plunger 52. For example, a cross-section of shaft 44 transverse to longitudinal axis 88 of shaft 44 may be concave such that at least a portion of a longitudinal surface of plunger 52 is exposed. Such a configuration may allow IMD 16 to be engaged with engagement mechanism 62 while at least a portion of IMD 16 is disposed outside of shaft 44, which may advantageously facilitate implantation of IMD 16. For example, placement of at least a portion of IMD 16 outside of shaft 44 (as opposed to the entire IMD 16 being disposed within shaft 44) may increase the reliability of releasing and implanting IMD 16. Further, because at least a portion of IMD 16 may be disposed outside of shaft 44, one or more dimensions (e.g., height, width, etc.) of IMD 16 may be greater than a corresponding one or more dimensions of shaft 44.

Fig. 4A-4C are conceptual diagrams of an example system 90 including tool 40 and IMD 16, illustrating operation of engagement mechanism 62. As shown in fig. 4A, IMD 16 may define or otherwise include engagement features 92 configured to engage or otherwise couple to engagement mechanism 62.

The engagement features 92 may include various features that facilitate engagement of the engagement mechanism 62 and the engagement features 92. For example, engagement feature 92 may include a first surface 94 of IMD 16 defining a first recess 96 configured to receive first projection 64A. Engagement feature 92 may also include a second surface 98 (not shown) of IMD 16 defining a second recess 100 (not shown) configured to receive second protrusion 64B. In some examples, first surface 94 and second surface 98 may be located on opposite sides of IMD 16. In some examples, the width of the channel 50 may gradually increase from a first distal point 104 to a second distal point 106 of the shaft 44. The second distal point 106 may be distal to the first distal point 104. The engagement mechanism 62 may be located distally of the first distal point 104 and the second distal point 106.

The first surface 94 may define a first slope extending from the proximal end 102 of the implantable medical device 14 to the first recess 96. Similarly, the second surface 98 may define a second ramp extending from the proximal end 102 to the second recess 100. When an operator of tool 40 inserts IMD 16 between projections 64 (e.g., as shown in fig. 4B), first surface 94 may guide first projection 64A toward first recess 96, and second surface 98 may guide second projection 64B toward second recess 100. For example, the width of the first ramp may taper from the proximal end 102 to the first recess 96 and the width of the second ramp may taper from the proximal end 102 to the second recess 100. The first and second recesses 96 and 100 may receive the first and second protrusions 64A and 64B, respectively.

Engagement mechanism 62 of tool 40 may be configured to release IMD 16. For example, as shown in fig. 4C, engagement mechanism 62 may release IMD 16 in response to a contact force exerted by plunger 52 on IMD 16 exceeding a reaction force of engagement mechanism 62. Plunger 52 may exert a contact force on IMD 16 by translating in a distal direction along the length of shaft 44 (e.g., in response to a first actuation of plunger actuator 54) until plunger 52 contacts IMD 16.

Fig. 5 is a flow chart illustrating an example technique for operating an example tunneling and insertion tool. According to the example of fig. 5, tool 40 may form a tunnel (500) for insertion of IMD 16. Tool 40 may translate plunger 52 in a distal direction along the length of shaft 44 such that distal end 60 is disposed beyond distal end 48. In some examples, tool 40 may translate plunger 52 in response to a first actuation of plunger actuator 54. The first actuation of the plunger actuator 54 may be in a direction indicated by arrow 56. That is, the operator may perform a first actuation of the plunger actuator 54 by moving the plunger actuator 54 in a generally proximal direction until the plunger actuator 54 is in a first position (as shown in fig. 3A).

To prevent translation of plunger 52 in a proximal direction along the length of shaft 44, tool 40 may engage lock 78. In some examples, when the plunger actuator 54 is in the first position, the tool 40 may engage the lock 78 in response to the first actuation of the lock actuator 66 such that an operator does not need to apply a proximal force to the plunger actuator 54 to maintain the position of the plunger 52. When desired (e.g., after forming a tunnel), the operator may disengage the lock 78 by performing a second actuation of the lock actuator 66.

The operator may position the distal end 60 (which may be disposed beyond the distal end 48) proximate to an access site on the patient's body. For example, the operator may position the distal end 60 generally orthogonal to the superficial incision of the access site. An operator may apply a distal force to the tool 40 to press the distal end 60 toward and into the access site. In some cases, the distal end 48 may be at least partially inserted into the access site.

Tool 40 may engage IMD 16 (502). For example, the engagement feature 92 may engage with the engagement mechanism 62. In some examples, the first recess 96 and the second recess 100 may receive the first projection 64A and the second projection 64B, respectively. When engagement mechanism 62 and engagement feature 92 are coupled, tool 40 may maintain IMD 16 in a fixed position relative to tool 40 as IMD 16 is advanced into the patient. As such, to advance IMD 16, the operator may apply a distal force to tool 40. To enable engagement of the engagement feature 92 with the engagement mechanism 62, the distal end 60 of the plunger 52 may be disposed within the shaft 44. This configuration of tool 40 may correspond to plunger actuator 54 being in the second position (as shown in fig. 3B). Thus, in examples where distal end 60 is initially disposed beyond distal end 48 of shaft 44 (e.g., to form a tunnel), an operator may perform a second actuation of plunger actuator 54 such that distal end 60 is disposed within shaft 44, thereby creating a space that allows IMD 16 to be positioned between protrusions 64.

Tool 40 may release IMD 16 (504). For example, in response to an operator using tool 40 to deliver IMD 16 to target site 24 in a tunnel formed by tool 40 via a tunnel formed by tool 40, plunger 52 may exert a contact force on IMD 16 that exceeds the reaction force of engagement mechanism 62 such that engagement mechanism 62 and engagement feature 92 are disengaged (e.g., protrusion 64 is no longer disposed within first recess 96 and second recess 100). In some examples, the plunger 52 may apply the contact force in response to a first actuation of the plunger actuator 54, which, as described above, may correspond to moving the plunger actuator 54 in a generally proximal direction. Such a configuration may advantageously reduce the likelihood of accidental release of IMD 16 because an operator is less likely to apply a distal force to tool 40 (e.g., while advancing IMD 16) and simultaneously move plunger actuator 54 in a generally proximal direction (as opposed to a generally distal direction).

The present disclosure includes various embodiments, such as the following embodiments.

Example 1: a tool, the tool comprising: a handle; a plunger actuator proximate the handle; a shaft extending from the handle, wherein the shaft includes a proximal end and a distal end, and wherein the shaft defines a channel extending along a length of the shaft; a plunger disposed at least partially within the channel, wherein a first actuation of the plunger actuator translates the plunger in a distal direction along the length of the shaft, and wherein a second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft; and an engagement mechanism disposed on the distal end, wherein the engagement mechanism is configured to: engaging the implantable medical device; and releasing the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in the distal direction along the length of the shaft.

Example 2: the tool of embodiment 1, further comprising a cam that rotates corresponding to the first actuation of the plunger actuator and the second actuation of the plunger actuator, wherein the cam is operably coupled to the plunger.

Example 3: the tool of embodiment 1 or 2, wherein the distal end of the plunger is configured to be disposed beyond the distal end of the shaft in response to the first actuation of the plunger actuator.

Example 4: the tool according to any one of embodiments 1-3, wherein the plunger is coupled to a spring, wherein the spring is configured to prevent translation of the plunger in the distal direction along the length of the shaft.

Example 5: the tool of any one of embodiments 1-4, further comprising: a lock actuator proximate the handle; and a lock, wherein a first actuation of the lock actuator causes the lock to engage, thereby preventing translation of the plunger along the length of the shaft, and wherein a second actuation of the lock actuator causes the lock to disengage.

Example 6: the tool of any one of embodiments 1-5, wherein the distal end of the plunger is configured to tunnel into tissue to form a passageway for advancing the implantable medical device.

Example 7: the tool of any one of embodiments 1-6, wherein the shaft defines a first protrusion and a second protrusion at the distal end, and wherein the engagement mechanism defines a gap between the first protrusion and the second protrusion.

Example 8: the tool of any one of embodiments 1-7, wherein the width of the channel increases gradually from a first distal point on the shaft to a second distal point on the shaft, wherein the second distal point is distal to the first distal point, and wherein the engagement mechanism is distal to the first distal point and the second distal point.

Example 9: the tool according to any one of embodiments 1-8, wherein a cross-section of the shaft transverse to a longitudinal axis of the shaft along the length of the shaft is concave.

Example 10: the tool of any one of embodiments 1-9, wherein the engagement mechanism is formed of an elastic material.

Example 11: a system comprising an implantable medical device, the implantable medical device comprising: a handle; a plunger actuator proximate the handle; a shaft extending from the handle, wherein the shaft includes a proximal end and a distal end, and wherein the shaft defines a channel extending along a length of the shaft; a plunger disposed at least partially within the channel, wherein a first actuation of the plunger actuator translates the plunger in a distal direction along the length of the shaft, and wherein a second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft; and an engagement mechanism disposed on the distal end, wherein the engagement mechanism is configured to: engaging an engagement feature of the implantable medical device and releasing the engagement feature of the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in the distal direction along the length of the shaft.

Example 12: the system of embodiment 11, wherein the shaft defines a first protrusion and a second protrusion at the distal end, wherein the engagement mechanism defines a gap between the first protrusion and the second protrusion, and wherein the engagement feature comprises: a first surface of the implantable medical device, the first surface defining a first recess configured to receive the first protrusion; and a second surface of the implantable medical device, the second surface defining a second recess configured to receive the second protrusion.

Example 13: the system of embodiment 12, wherein the first surface defines a first ramp extending from a proximal end of the implantable medical device to the first recess, wherein a width of the first ramp gradually decreases from the proximal end to the first recess, wherein the second surface defines a second ramp extending from the proximal end of the implantable medical device to the second recess, and wherein a width of the second ramp gradually decreases from the proximal end to the second recess.

Example 14: the system of any one of embodiments 11-13, wherein the implantable medical device is configured to be coupled to a lead.

Example 15: the system of embodiment 14, wherein the lead, when coupled to the implantable medical device, extends eccentrically from the proximal end of the implantable medical device.

Example 16: the system of any one of embodiments 11-15, wherein the implantable medical device comprises a pacemaker.

Example 17: the system of any one of embodiments 11-16, wherein the tool further comprises a cam that rotates corresponding to the first actuation of the plunger actuator and the second actuation of the plunger actuator, wherein the cam is operably coupled to the plunger.

Example 18: the system of any one of embodiments 11-17, wherein a distal end of the plunger is configured to be disposed beyond the distal end of the shaft in response to the first actuation of the plunger actuator.

Example 19: the system of any one of embodiments 11-18, wherein the plunger is coupled to a spring, wherein the spring is configured to prevent translation of the plunger in the distal direction along the length of the shaft.

Example 20: the system of any of embodiments 11-19, wherein the tool further comprises: a lock actuator proximate the handle; and a lock, wherein a first actuation of the lock actuator causes the lock to engage, thereby preventing translation of the plunger along the length of the shaft, and wherein a second actuation of the lock actuator causes the lock to disengage.

Example 21: the system of any one of embodiments 11-20, wherein the distal end of the plunger is configured to tunnel into tissue to form a passageway for advancing the implantable medical device.

Example 22: the system of any one of embodiments 11-21, wherein the shaft defines a first protrusion and a second protrusion at the distal end, and wherein the engagement mechanism defines a gap between the first protrusion and the second protrusion.

Example 23: the system of any one of embodiments 11-22, wherein a width of the channel increases gradually from a first distal point on the shaft to a second distal point on the shaft, wherein the second distal point is distal to the first distal point, and wherein the engagement mechanism is distal to the first distal point and the second distal point.

Example 24: the system of any one of embodiments 11-23, wherein a cross-section of the shaft transverse to a longitudinal axis of the shaft along the length of the shaft is concave.

Example 25: the system of any of embodiments 11-24, wherein the engagement mechanism is formed of an elastic material.

Example 26: a method, the method comprising: translating the plunger in a distal direction along a length of a shaft of the tool in response to a first actuation of a plunger actuator of the tool to form a tunnel in a body of a patient; translating the plunger in a proximal direction along the length of the shaft in response to a second actuation of the plunger actuator; engaging the implantable medical device via an engagement mechanism of the tool; and releasing the implantable medical device in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism as the plunger translates in the distal direction along the length of the shaft.

Example 27: the method of embodiment 26, further comprising: engaging a lock in response to a first actuation of the lock actuator of the tool, wherein engagement of the lock prevents translation of the plunger along the length of the shaft; and disengaging the lock in response to a second actuation of the lock actuator.

Various embodiments have been described. These and other embodiments are within the scope of the following claims.

Claims (15)

1. A tool, the tool comprising:

a handle;

A plunger actuator proximate to the handle;

A shaft extending from the handle, wherein the shaft includes a proximal end and a distal end, and wherein the shaft defines a channel extending along a length of the shaft;

A plunger disposed at least partially within the channel, wherein a first actuation of the plunger actuator translates the plunger in a distal direction along the length of the shaft, and wherein a second actuation of the plunger actuator translates the plunger in a proximal direction along the length of the shaft; and

An engagement mechanism disposed on the distal end, wherein the engagement mechanism is configured to:

Engaging an implantable medical device, and

When the plunger translates in the distal direction along the length of the shaft, the implantable medical device is released in response to a contact force exerted by the plunger on the implantable medical device exceeding a reaction force of the engagement mechanism.

2. The tool of claim 1, further comprising a cam that rotates corresponding to the first actuation of the plunger actuator and the second actuation of the plunger actuator, wherein the cam is operably coupled to the plunger.

3. The tool of claim 1, wherein a distal end of the plunger is configured to be disposed beyond the distal end of the shaft in response to the first actuation of the plunger actuator.

4. The tool of claim 3, wherein the plunger is coupled to a spring, wherein the spring is configured to prevent translation of the plunger in the distal direction along the length of the shaft.

5. The tool of claim 4, further comprising:

A lock actuator proximate to the handle; and

A lock, wherein a first actuation of the lock actuator causes the lock to engage, thereby preventing translation of the plunger along the length of the shaft, and wherein a second actuation of the lock actuator causes the lock to disengage.

6. The tool of any one of claims 1-5, wherein the distal end of the plunger is configured to tunnel into tissue to form a passageway for advancing the implantable medical device.

7. The tool of any one of claims 1-5, wherein the shaft defines a first protrusion and a second protrusion at the distal end, and wherein the engagement mechanism defines a gap between the first protrusion and the second protrusion.

8. The tool of any one of the preceding claims, wherein the width of the channel increases gradually from a first distal point on the shaft to a second distal point on the shaft, wherein the second distal point is distal to the first distal point, and wherein the engagement mechanism is distal to the first distal point and the second distal point.

9. A tool according to any preceding claim, wherein a cross-section of the shaft transverse to a longitudinal axis of the shaft along the length of the shaft is concave.

10. A tool according to any preceding claim, wherein the engagement means is formed of an elastic material.

11. A system, the system comprising:

An implantable medical device comprising an engagement feature; and

The tool of claim 1.

12. The system of claim 11, wherein the shaft defines a first protrusion and a second protrusion at the distal end, wherein the engagement mechanism defines a gap between the first protrusion and the second protrusion, and wherein the engagement feature comprises:

A first surface of the implantable medical device, the first surface defining a first recess configured to receive the first protrusion; and

A second surface of the implantable medical device, the second surface defining a second recess configured to receive the second protrusion.

13. The system of claim 12, wherein the first surface defines a first ramp extending from a proximal end of the implantable medical device to the first recess, wherein a width of the first ramp gradually decreases from the proximal end to the first recess, wherein the second surface defines a second ramp extending from the proximal end of the implantable medical device to the second recess, and wherein a width of the second ramp gradually decreases from the proximal end to the second recess.

14. The system of claim 11, wherein the implantable medical device is configured to be coupled to a lead.

15. The system of claim 14, wherein the lead, when coupled to the implantable medical device, extends eccentrically from a proximal end of the implantable medical device.