Tools and systems for implanting and / or retrieving a leadless cardiac pacemaker device having a helical fixation element

Abstract

The present invention relates to an implantation and / or retrieval device for a leadless cardiac pacing device, which may include: a first elongated shaft including a lumen; a second elongated shaft slidably disposed in the lumen of the first elongated shaft; an end cap assembly fixedly attached to a distal end of the first elongated shaft; and a plurality of wires attached to the second elongated shaft and extending distally from the end cap assembly, the plurality of wires being movable relative to the end cap assembly. The plurality of wires are configured to engage a proximal hub of the leadless cardiac pacing device. The plurality of wires form a plurality of wire loops extending distally from the end cap assembly.

Description

[0001] Cross-application of related applications

[0002] This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62 / 898,701, filed on September 11, 2019, entitled “TOOLS AND SYSTEMS FOR IMPLANTING AND / OR RETRIEVING A LEADLESS CARDIAC PACING DEVICE WITH HELIX FIXATION,” the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to medical devices and methods for making and / or using medical devices. More particularly, the present disclosure relates to leadless cardiac devices and methods, such as leadless cardiac pacing devices and methods, and delivery and retrieval devices and methods for such leadless devices. Background Art

[0004] A wide variety of medical devices have been developed for medical applications, such as cardiac applications. Some of these devices include catheters, guidewires, pacemakers, and the like, as well as delivery devices and / or systems for delivering such devices. These devices are manufactured using any of a variety of different manufacturing methods and can be used according to any of a variety of methods. Each of the known medical devices, delivery systems, and methods has certain advantages and disadvantages. There is a continuing need to provide alternative medical devices and delivery devices, as well as alternative methods for manufacturing and using medical devices and delivery devices. Summary of the Invention

[0005] In one example, an implantation and / or retrieval apparatus for a leadless cardiac pacing device may include: a first elongated shaft including a lumen; a second elongated shaft slidably disposed within the lumen of the first elongated shaft; an end cap assembly fixedly attached to a distal end of the first elongated shaft; and a plurality of wires attached to the second elongated shaft and extending distally from the end cap assembly, the plurality of wires being movable relative to the end cap assembly. The plurality of wires are configured to engage a proximal hub of the leadless cardiac pacing device. The plurality of wires form a plurality of wire loops extending distally from the end cap assembly.

[0006] Additionally or alternatively, the end cap assembly includes an insert secured within an outer housing fixedly attached to the distal end of the first elongated shaft.

[0007] Additionally or alternatively, the distal-most surface of the insert is flush with the distal-most end surface of the outer housing.

[0008] Additionally or alternatively, the insert includes a plurality of holes extending through the insert, wherein the plurality of holes are configured to receive the plurality of wires.

[0009] Additionally or alternatively, each of the plurality of holes curves radially outward in a distal direction.

[0010] Additionally or alternatively, the insert is a one-piece structure.

[0011] Additionally or alternatively, the insert includes a plurality of insert members, each insert member including at least a portion of one or more of the plurality of apertures extending through the insert member.

[0012] Additionally or alternatively, each of the plurality of holes is configured to receive more than one wire of the plurality of wires.

[0013] Additionally or alternatively, circumferentially adjacent wire loops in the plurality of wire loops cross each other when viewed in the axial direction.

[0014] Additionally or alternatively, an implantation and / or retrieval apparatus for a leadless cardiac pacing device may include: a first elongated shaft including a lumen; an end cap assembly fixedly attached to a distal end of the first elongated shaft; and a plurality of wires extending through the end cap assembly and forming a plurality of wire loops distal to the end cap assembly, the plurality of wires being movable through the end cap assembly between a first position and a second position distal to the first position. The plurality of wire loops are configured to secure a proximal hub of the leadless cardiac pacing device relative to the end cap assembly in the first position.

[0015] Additionally or alternatively, the end cap assembly includes an insert secured within the outer housing. The insert may include a distal-most surface flush with the distal-most surface of the outer housing and a plurality of apertures extending through the insert and open distally. The plurality of wire loops are configured to secure a proximal hub of the leadless cardiac pacing device against the distal-most surface of the insert in a first position.

[0016] Additionally or alternatively, circumferentially adjacent wire loops in the plurality of wire loops cross each other when viewed in the axial direction.

[0017] Additionally or alternatively, the plurality of wires are configured to transmit rotational motion of the first elongated shaft to the proximal hub at the first location.

[0018] Additionally or alternatively, the plurality of wire loops includes a first wire loop passed through a first pair of the plurality of holes, a second wire loop passed through a second pair of the plurality of holes, and a third wire loop passed through a third pair of the plurality of holes.

[0019] Additionally or alternatively, one of the second pair of holes in the plurality of holes is circumferentially disposed between the first pair of holes in the plurality of holes, and one of the third pair of holes in the plurality of holes is circumferentially disposed between the second pair of holes in the plurality of holes.

[0020] Additionally or alternatively, the distal end segment of the first wire loop is parallel to the distal end segment of the third wire loop, and the distal end segment of the first wire loop is perpendicular to the distal end segment of the second wire loop.

[0021] Additionally or alternatively, a system may include: a leadless cardiac pacing device comprising a body, a proximal hub, and a helical fixation member opposite the proximal hub; a catheter; a first elongated shaft slidably disposed within the catheter, the first elongated shaft comprising a lumen and a proximal handle; a second elongated shaft slidably disposed within the lumen of the first elongated shaft; an end cap assembly comprising an outer housing fixedly attached to a distal end of the first elongated shaft and an insert fixed within the outer housing; and a plurality of wires fixedly attached to the second elongated shaft and extending distally from the end cap assembly to form a plurality of wire loops translatable between a first position and a second position distal to the first position. The plurality of wire loops are configured to engage the proximal hub of the leadless cardiac pacing device in the first position.

[0022] Additionally or alternatively, the end cap assembly is free of any structure configured to engage a side surface of the proximal hub.

[0023] Additionally or alternatively, the plurality of wires are configured to transmit rotational motion of the first elongated shaft to the proximal hub at the first location.

[0024] Additionally or alternatively, the leadless cardiac pacing device includes a neck extending longitudinally from the body to the proximal hub.In a first position, the plurality of wire loops include three or more intersecting distal end segments to form a bounded opening for receiving the neck therethrough.

[0025] The above summary of some embodiments, aspects and / or examples is not intended to describe every embodiment or every implementation of the present disclosure. The following figures and detailed description more particularly exemplify these embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present disclosure may be more fully understood upon consideration of the following detailed description taken in conjunction with the accompanying drawings, in which:

[0027] Figure 1 is a schematic diagram of an exemplary leadless cardiac pacemaker device implanted in the heart;

[0028] Figure 2 is a side view of an exemplary implantable leadless cardiac pacing device;

[0029] Figure 3Aspects of a system for implanting and / or retrieving a leadless cardiac pacing device are shown;

[0030] Figure 3A yes Figure 3 A detailed view of a portion of a system;

[0031] Figure 4A Shown along Figure 3A an end view of a portion of the system shown by line 4-4;

[0032] Figure 4B Shown along Figure 3A An end view of a portion of an alternative configuration of the system shown on line 4-4;

[0033] Figure 4C Shown along Figure 3A An end view of a portion of an alternative configuration of the system shown on line 4-4;

[0034] Figure 5 Shown Figure 3 all aspects of the system;

[0035] Figure 5A yes Figure 5 A detailed view of a portion of a system;

[0036] Figure 6 It shows Figure 3 and Figure 5 Exploded views of selected aspects of the system;

[0037] Figure 7 is a cross-sectional view of an exemplary insert according to the present disclosure;

[0038] Figure 8 Shown Figure 3 and Figure 5 aspects of alternative configurations of the system;

[0039] Figure 9 It shows Figure 8 Exploded views of selected aspects of the system;

[0040] Figure 10 Shown Figure 8-9 aspects of exemplary insert components of the system;

[0041] Figure 11 Shown Figure 3 and Figure 5 aspects of alternative configurations of the system;

[0042] Figure 12-20 is a series of schematic diagrams illustrating the delivery and retrieval of a leadless cardiac pacing device into and from a patient's heart.

[0043] While the present disclosure is susceptible to various modifications and alternative forms, details thereof have been shown by way of example in the accompanying drawings and will be described in detail. However, it should be understood that the intention is not to limit the aspects of the present disclosure to the specific embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. DETAILED DESCRIPTION

[0044] The following description should be read with reference to the accompanying drawings, which are not necessarily drawn to scale, in which similar reference numerals indicate similar elements throughout the multiple views. The detailed description and the accompanying drawings are intended to illustrate but not limit the claimed invention. Those skilled in the art will recognize that the various elements described and / or shown may be arranged in various combinations and configurations without departing from the scope of this disclosure. The detailed description and the accompanying drawings illustrate example embodiments of the claimed invention. However, for clarity and ease of understanding, although each feature and / or element may not be shown in each drawing, unless otherwise specified, feature(s) and / or element(s) may be understood to be present.

[0045] For the following defined terms, these definitions shall apply unless a different definition is given in the claims or elsewhere in this specification.

[0046] All numerical values ​​herein are considered to be modified by the term "about", whether or not explicitly stated. In the context of numerical values, the term "about" generally refers to a range of numbers that one skilled in the art would consider to be equivalent to the value (e.g., having the same function or result). In many cases, the term "about" can include a number rounded to the nearest significant figure. Unless otherwise specified, other uses of the term "about" (e.g., in a context other than numerical values) can be considered to have its common and customary (multiple) definitions, as understood from the context of the specification and consistent with the context of the specification.

[0047] The recitation of numerical ranges by endpoints includes all numbers within that range, inclusive of the endpoints (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0048] Although some suitable sizes, ranges and / or values ​​are disclosed in connection with various components, features and / or specifications, those skilled in the art, having benefit of this disclosure, will understand that the desired sizes, ranges and / or values ​​may deviate from those explicitly disclosed.

[0049] As used in this specification and the appended claims, the singular forms "a", "an" and "the" include plural referents unless the content clearly indicates otherwise. As used in this specification and the appended claims, the term "or" is generally used in a sense that includes "and / or" unless the content clearly indicates otherwise. It should be noted that, for ease of understanding, certain features of the present disclosure may be described in the singular, even if these features may be plural or repeated in the disclosed (multiple) embodiments. Each instance of a feature may be included and / or contained in (multiple) single disclosures, unless expressly provided to the contrary. For the purposes of simplicity and clarity, not all elements of the disclosed invention must be shown in each figure or discussed in detail below. However, it should be understood that the discussion below may apply equally to any and / or all components having multiple parts, unless expressly provided to the contrary. In addition, for clarity, not all instances of certain elements or features are shown in each figure.

[0050] Related terms such as "proximal," "distal," "advance," "retract," and variations thereof may generally be considered relative to the positioning, orientation, and / or operation of various elements of a user / operator / manipulator of the device, with "proximal" and "retracted" meaning or referring closer to or toward the user, and "distal" and "advance" meaning or referring farther from or away from the user. In some cases, the terms "proximal" and "distal" may be arbitrarily designated to aid in understanding the present disclosure, and such cases will be clear to those skilled in the art. Other related terms, such as "upstream," "downstream," "inflow," and "outflow," refer to the direction of fluid flow, such as within a lumen of a subject, a lumen of a vessel, or within a device.

[0051] The term "range" may be understood to mean the maximum measurement of a described or identified dimension, unless the described range or dimension is preceded or identified as a "minimum value," in which case it may be understood to mean the minimum measurement of the described or identified dimension. For example, an "external range" may be understood to mean an external dimension, a "radial range" may be understood to mean a radial dimension, a "longitudinal range" may be understood to mean a longitudinal dimension, and so on. Each instance of "range" may be different (e.g., axial, longitudinal, transverse, radial, circumferential, etc.) and will be clear to one skilled in the art from the context of individual use. Generally, a "range" may be considered to be the maximum possible dimension measured for the intended use, while a "minimum range" may be considered to be the minimum possible dimension measured for the intended use. In some cases, a "range" may generally be measured orthogonally within a plane and / or cross-section, but may be measured in different ways, such as, but not limited to, an angle, radially, circumferentially (e.g., along an arc), and so on, as may be apparent from the particular context.

[0052] The terms "integral" and "unitary" generally refer to one or more elements that are made or composed of a single structure or basic unit / element. Integral elements and / or unitary elements shall exclude structures and / or features formed by assembling or otherwise coupling together multiple discrete elements.

[0053] Note that references in the specification to "an embodiment," "some embodiments," "other embodiments," etc. indicate that the described embodiment(s) may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it will be within the scope of one's knowledge to implement the particular feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described, unless expressly indicated to the contrary. That is, the various individual elements described below, even if not explicitly shown in a particular combination, are considered to be combinable or arrangable with each other to form other additional embodiments, or to supplement and / or enrich the described embodiment(s), as understood by one of ordinary skill in the art.

[0054] For clarity, certain identifying numerical nomenclatures (e.g., first, second, third, fourth, etc.) may be used throughout the specification and / or claims to name and / or distinguish various described and / or claimed features. It should be understood that the numerical nomenclature is not restrictive but merely exemplary. In some embodiments, for brevity and clarity, the previously used numerical nomenclature may be modified and deviated from. That is, a feature identified as a "first" element may later be referred to as a "second" element, a "third" element, etc., or may be omitted entirely, and / or different features may be referred to as a "first" element. The meaning and / or name in each case will be clear and distinct to a skilled practitioner.

[0055] A cardiac pacemaker provides electrical stimulation to cardiac tissue, causing the heart to contract and thereby pump blood through the vascular system. Conventional pacemakers typically include electrical leads extending from a pulse generator implanted subcutaneously or submuscularly to electrodes positioned adjacent to the inner or outer wall of a cardiac chamber. As an alternative to conventional pacemakers, self-contained or leadless cardiac pacemakers have been proposed. A leadless cardiac pacemaker is a small capsule that is typically secured to an intracardiac implant site in or around a cardiac chamber. The small capsule typically includes bipolar pacing / sensing electrodes, a power source (e.g., a battery), and associated electronic circuitry for controlling the pacing / sensing electrodes and thereby providing electrical stimulation to cardiac tissue and / or sensing physiological conditions. In some cases, a leadless cardiac pacemaker may include proximal and / or distal extensions extending from the small capsule, wherein the extension(s) may include one or more pacing / sensing electrodes. The capsule can be delivered to the heart using a delivery device that can be advanced through the femoral vein, into the inferior vena cava, into the right atrium, and into the coronary sinus and blood vessels extending through and / or to the coronary sinus. Therefore, it may be desirable to provide a cardiac pacing device and a delivery device that facilitates advancement through the vasculature.

[0056] The leadless cardiac pacing devices described herein can detect and treat arrhythmias, and more specifically, deliver electrical stimulation therapy to the right atrium, left atrium, right ventricle, and / or left ventricle of a patient's heart. For example, one or more devices may be implanted on or within a patient's heart, and one or more devices may be configured to deliver electrical stimulation therapy to one or more chambers of the patient's heart and / or treat one or more types of detected arrhythmias according to one or more treatment programs. Some exemplary electrical stimulation therapies include bradycardia therapy, cardiac resynchronization therapy (CRT), anti-tachycardia pacing (ATP) therapy, defibrillation and / or cardioversion therapy, and the like. Some exemplary arrhythmias include atrial fibrillation or atrial flutter, ventricular fibrillation, and tachycardia.

[0057] Although various features of a leadless cardiac pacing device are described herein, alternative and / or additional features of an exemplary leadless cardiac pacing device are discussed in U.S. Provisional Patent Application, Serial No. 62 / 826,496, filed on March 29, 2019, entitled “SYSTEMS AND METHODS FOR TREATING CARDIAC ARRHYTHMIAS,” which is hereby incorporated by reference for all purposes; and U.S. Provisional Patent Application, Serial No. 62 / 826,507, filed on March 29, 2019, entitled “SYSTEMS AND METHODS FOR TREATING CARDIACARRHYTHMIAS,” which is hereby incorporated by reference for all purposes. Hereinafter, these references incorporated by reference are referred to as “the incorporated references.”

[0058] Figure 1 is a conceptual diagram of an illustrative system for delivering electrical stimulation therapy to a patient's heart, including delivering electrical stimulation therapy to the right atrium, left atrium, right ventricle, and / or left ventricle of the patient's heart. Figure 1 An illustrative leadless cardiac pacing device 20 is shown implanted in and around the heart 10. Figure 1 The heart 10 depicts the right atrium 11, the left atrium 12, the right ventricle 13, the left ventricle 14, the coronary sinus 15, the coronary sinus ostium 16, the great cardiac vein 17, and the septum 18. Figure 1 In FIG. 1 , the coronary sinus 15 and the great cardiac vein 17 are depicted with dashed lines because these features are on the posterior side of the heart 10 and are typically seen from the Figure 1 Although the leadless cardiac pacemaker device 20 is shown as implanted and extending into the coronary sinus 15 and at least a portion of the leadless cardiac pacemaker device 20 is visible from the Figure 1 The leadless cardiac pacing device 20 is not typically visible in the view of FIG, but for clarity, the entire leadless cardiac pacing device 20 is depicted in solid lines. In some cases, approximately 50% of the length of the body 22 of the leadless cardiac pacing device 20 is inserted into the coronary sinus 15, with the proximal region of the body 22 located in the right atrium 11. In some cases, approximately 25%-75% of the distal-most portion of the length of the body 22 of the leadless cardiac pacing device 20 can be inserted into the coronary sinus 15, with the remaining proximal region of the body 22 located in the right atrium 11.

[0059] exist Figure 1In the example of the present invention, the leadless cardiac pacing device 20 includes a body 22 having a proximal end and a distal end and a distal extension 24 extending distally from the distal end of the body 22. However, in some cases, the distal extension 24 may not be included and / or one or more other distal and / or proximal extensions may be included. The body 22 does not necessarily have the same cross-sectional shape along its entire length. When implanted, the body 22 may be completely or partially disposed within the coronary sinus 15 of the patient's heart 10, and the distal extension 24 may be completely or partially disposed within a blood vessel extending from the coronary sinus 15 (e.g., the great cardiac vein 17, the anterior interventricular vein, another lateral descending vessel, etc.).

[0060] The body 22 can have any size suitable for implantation at a target location within the patient's heart 10. In one example, the body 22 can have a cross-sectional diameter or area sufficient to fit within the coronary sinus 15, which can vary from about 0.24 inches (6 mm) to about 0.6 inches (15 mm). In various embodiments, the diameter of the body 22 can range from about 0.1 inches (2.54 mm) to about 0.4 inches (10 mm). The body 22 can be sized to be implanted within coronary sinuses of varying sizes while still allowing adequate blood flow through the coronary sinus 15.

[0061] In some embodiments, the leadless cardiac pacing device 20 may include one or more electrodes. In one example, the body 22 of the leadless cardiac pacing device 20 may support a first electrode 26 and a second electrode 28, while the distal extension 24 may support the distal electrodes. In some cases, the distal extension 24 may include multiple electrodes (e.g., a first proximal ring electrode 30, a second proximal ring electrode 32, a third proximal ring electrode 34, a distal ring electrode 36, and / or one or more other electrodes). Although the electrodes described may be shown as ring electrodes, other electrode types may be used depending on the application.

[0062] In some cases, the first electrode 26 can be formed on, along, and / or from the body 22, and the second electrode 28 can be formed on, along, and / or from a fixation member 50 (discussed in more detail below) extending from the body 22. In one example, the body 22 can be formed at least in part from a conductive material, and an exposed surface of such conductive material can at least in part form the first electrode 26. Additionally or alternatively, the second electrode 28 can be formed from one or more exposed conductive surface portions of the fixation member 50 that can be exposed to the patient's cardiac tissue. Various arrangements of the electrodes 26, 28, including location, shape, material(s), etc., are contemplated. Alternative and / or additional electrode configurations for the leadless cardiac pacing device 20 are discussed in the references incorporated herein.

[0063] When provided, the electrodes of the leadless cardiac pacing device 20 can be used to deliver electrical stimulation to the heart 10 and / or sense one or more physiological signals. In some cases, the leadless cardiac pacing device 20 can use one or more electrodes (e.g., electrodes 26-36 or other electrodes) to communicate with one or more other devices, such as, but not limited to, one or more other leadless cardiac pacemakers and / or implantable cardioverter-defibrillators. In some cases, the leadless cardiac pacing device 20 can communicate using conducted communication techniques and can deliver and / or receive communication signals via one or more electrodes (e.g., electrodes 26-36 or other electrodes). In some embodiments, the leadless cardiac pacing device 20 can include one or more communication wires configured to function as an antenna for wirelessly communicating with and / or receiving electrical energy from one or more other devices.

[0064] In some cases, the leadless cardiac pacing device 20 may include a neck extending longitudinally from the body 22 to a proximal hub 38 (e.g., a docking hub or other member) disposed generally proximal to the body 22. During implantation, the proximal hub 38 may be releasably coupled to an implantation and / or retrieval device ( Figure 1 When coupled, the motion of the implantation and / or retrieval device can be transferred to the leadless cardiac pacing device 20 and / or the body 22, thereby allowing a user, such as a physician, to deploy the leadless cardiac pacing device 20 and / or the body 22 into position within the heart 10, for example, into or proximate the coronary sinus 15. The implantation and / or retrieval device can manipulate the leadless cardiac pacing device 20 longitudinally and / or rotationally.

[0065] In some cases, the leadless cardiac pacing device 20 may be delivered from a delivery catheter ( Figure 1 The leadless cardiac pacing device 20 may be delivered via a delivery catheter (not shown), and the portion of the delivery catheter surrounding the body 22 may conform to the body 22 to establish a secure connection between the delivery catheter and the body 22. When the leadless cardiac pacing device 20 is in place, the delivery catheter may be retracted, or an implantation and / or retrieval device may be used to push the body 22 out of the delivery catheter and / or otherwise adjust the position of the leadless cardiac pacing device 20. In some embodiments, the implantation and / or retrieval device may apply a rotational torque to the body 22 to anchor the leadless cardiac pacing device 20 to the cardiac tissue.

[0066] Although the distal extension 24 is Figure 1, but in some cases, the leadless cardiac pacing device 20 may not include the distal extension 24. In the case where the leadless cardiac pacing device 20 includes the distal extension 24, the distal extension 24 may extend distally from the distal end of the body 22. In addition, when the distal extension 24 is included, the distal extension 24 may extend into the coronary sinus 15 and be fixed within the coronary sinus 15. In some cases, the distal extension 24 may extend through the coronary sinus 15 and into the great cardiac vein 17 (e.g., Figure 1 shown) or one or more other blood vessels extending from the coronary sinus 15 or the great cardiac vein 17.

[0067] The distal extension 24 may include a proximal end 24a and a distal end 24b. The distal end 24b of the distal extension 24 may include one or more engagement members, but this is not required. When an engagement member is included, the engagement member may help secure the distal end 24b of the distal extension 24 within the coronary sinus 15 or the great cardiac vein 17. The engagement member and / or the engagement member may include one or more electrodes or wire loops and may act as an antenna to communicate with one or more other devices and / or receive electrical energy from one or more other devices. For example, the leadless cardiac pacing device 20 may receive energy transfer via the electrodes and / or wire loops of the engagement member and / or communicate using inductive and / or conductive communication techniques.

[0068] In some embodiments, the electrodes 30-36 on the distal extension 24 can be used to deliver electrical stimulation to the heart 10. For example, the leadless cardiac pacing device 20 can deliver electrical stimulation to the left ventricle 14 of the heart 10 via a set of one or more electrodes (e.g., from a set of electrodes 30-36 or other electrodes). In some embodiments, the leadless cardiac pacing device 20 can use two or more electrodes 30-36 to deliver electrical stimulation to the left ventricle 14 of the heart 10 simultaneously or with a delay (e.g., via multi-electrode pacing). In some embodiments, the leadless cardiac pacing device 20 can use one or more of the electrodes 30-36 to communicate with one or more other devices (e.g., the electrodes 30-36 can act as antennas). For example, the leadless cardiac pacing device 20 can receive energy transfer and / or communicate using inductive or conductive communication techniques via one or more electrodes 30-36.

[0069] The electrodes 26-36 and / or other electrodes on the leadless cardiac pacing device 20 can sense electrical signals, provide electrical stimulation signals, or sense electrical signals and provide electrical stimulation signals. Signal processing, communication, and / or generation of therapy pulses can occur in any portion of the leadless cardiac pacing device where an appropriate processing module can be located. In one example, signal processing, communication, and generation of therapy pulses for the electrodes of the leadless cardiac pacing device 20 (e.g., electrodes 26-36 and / or other electrodes) can occur within the body 22 or in a module supported by the body.

[0070] In some embodiments, the leadless cardiac pacing device 20 can be implanted as a single device (e.g., without an additional leadless cardiac pacing device or one or more implantable cardioverter-defibrillators) that can provide electrical stimulation to the right atrium 11, left atrium 12, right ventricle 13, and / or left ventricle 14 as needed. For example, the leadless cardiac pacing device 20 can be configured to deliver electrical stimulation to treat atrial fibrillation or atrial flutter according to a treatment program. In other cases, the leadless cardiac pacing device 20 can be implanted at one or more locations in and / or around the heart 10 in conjunction with other leadless cardiac pacing devices and / or one or more implantable cardioverter-defibrillators.

[0071] Figure 2 is a schematic diagram of an illustrative leadless cardiac pacing device 20. In some embodiments, body 22 may generally comprise a biocompatible material, such as a biocompatible metal and / or polymer, and may seal components of leadless cardiac pacing device 20 from fluid intrusion. Figure 2 The illustrated body 22 can have a generally straight, elongated shape extending along a central longitudinal axis. In some cases, the body 22 can be substantially cylindrical. However, the body 22 can have one or more other suitable shapes, including but not limited to having curved or angled portions to facilitate engagement of the tissue of the heart 10 with the electrodes of the leadless cardiac pacing device 20. Additional or alternative configurations of the body 22 are discussed in the references incorporated herein.

[0072] As described above, leadless cardiac pacing device 20 can have one or more electrodes, such as electrodes 26, 28, and / or other electrodes, which, in the example shown, are supported by body 22 as described herein. It is contemplated that, in some cases, body 22 can have a different number of electrodes, or no electrodes at all.

[0073] In some embodiments, leadless cardiac pacing device 20 can include a neck 46 extending from a proximal end of body 22 to a proximal hub 38. In some cases, neck 46 can have a first outer extent, and the proximal end of neck 46 can be connected to proximal hub 38 having a second outer extent. In some examples, the second outer extent of proximal hub 38 can be greater than the first outer extent of neck 46. Other configurations are also contemplated.

[0074] During implantation, refer to Figure 12-20 As discussed in more detail, implantation and / or retrieval of a device (e.g., Figure 3) can be releasably engaged and / or coupled to the proximal hub 38. When coupled, movement of the implantation and / or retrieval device can be transmitted to the body 22, thereby allowing a user to longitudinally position and / or rotate the leadless cardiac pacing device 20 during implantation. In some cases, the leadless cardiac pacing device 20 can include one half of an interlocking mechanism instead of or in addition to the neck 46 and proximal hub 38, and the implantation and / or retrieval device can have a second half of the interlocking mechanism that can releasably couple to the interlocking mechanism of the leadless cardiac pacing device 20. The interlocking mechanism can be configured to create a magnetic connection, a keyed connection, and / or other suitable connection. Additional and / or alternative interlocking mechanisms are described in the references incorporated herein.

[0075] In some cases, the body 22 can include a fixation member 50 and / or the fixation member 50 can extend from the body 22 opposite the proximal hub 38. In some embodiments, the fixation member 50 can be a helical fixation member and can include a distal tip 57, such as Figure 2 1. The fixation member 50 is shown in FIG. 1 and can be configured to retain the leadless cardiac pacing device 20 within the coronary sinus 15 of the heart 10 when the leadless cardiac pacing device 20 is implanted within the coronary sinus 15 of the heart 10. In some cases, the fixation member 50 is a helical coil having an outer diameter in the range of about 0.247 inches (6.274 mm) to about 0.275 inches (6.985 mm) and a pitch of about 0.050 inches (1.270 mm) to about 0.075 inches (1.905 mm) for at least one turn around the helical coil, but in some embodiments, the helical fixation member 50 can have one or more different diameters and / or different suitable pitches. The fixation member 50 can be formed of a material having a diameter suitable for penetrating and engaging cardiac tissue, being electrically conductive, and / or being flexible or bendable. Additional dimensions and / or features of the fixation member 50 are described in the references incorporated herein.

[0076] The fixation member 50 can be secured to the body 22 in any suitable manner. In one example, a proximal portion of the fixation member 50 (e.g., a proximal portion of the helical coil) can be embedded (e.g., molded) within the body 22, and a distal portion of the fixation member 50 (e.g., a distal portion of the helical coil) can extend from the body 22 and can be configured to engage cardiac tissue of the patient when the leadless cardiac pacing device is positioned within the patient. The distal portion of the fixation member 50 can be configured to extend about 0.5 to about 2.0 turns (or any amount therebetween) around the body 22. The fixation member 50 can be at least partially comprised of a material configured to penetrate and engage cardiac tissue that is electrically conductive, radiopaque, and / or flexible and / or has shape memory properties. Some suitable, but non-limiting, examples of materials for the fixation member 50 are described below.

[0077] In some instances, when the fixation member 50 engages tissue and an axial force is applied to the leadless cardiac pacing device 20, the fixation member 50 can straighten or elongate from its helical configuration. In some instances, when subjected to an axial force, the fixation member 50 can plastically deform and elongate from its helical configuration to a straightened configuration. This configuration of the fixation member 50 can facilitate removal of the leadless cardiac pacing device 20 and can reduce the risk of injury to the patient due to perforation or abrasion.

[0078] Although one fixation member 50 is depicted on the body 22, the body 22 may support one or more additional fixation members axially spaced apart from the fixation member 50. In other cases, the body 22 may not include a fixation member 50. In some cases, as described above, the fixation member 50 may include or form one or more electrodes (e.g., the second electrode 28 or other suitable electrodes) and / or may act as an antenna to communicate with and / or receive electrical energy from one or more other devices. For example, the leadless cardiac pacing device 20 may receive energy transfer via the electrodes of the fixation member 50 and / or communicate using inductive and / or conductive communication techniques.

[0079] In at least some cases, the body 22 may include a guidewire port 54 that extends through and / or opens to a side of the body 22, where the side extends from a first end to a second end of the body 22. In some cases, the guidewire port 54 may be configured to receive a guidewire. In cases where the leadless cardiac pacing device 20 includes a distal extension 24, the distal extension 24 may include a corresponding guidewire port located at the distal end of the distal end 24b of the distal extension 24. In this case, the guidewire may be positioned beneath the great cardiac vein 17 (or other vessel in communication with the coronary sinus 15). The leadless cardiac pacing device 20 may be tracked over the guidewire by passing the distal extension 24 through the proximal end of the guidewire and then advancing the leadless cardiac pacing device 20 over the guidewire until it is in place. In embodiments where the leadless cardiac pacing device 20 does not include a distal extension 24, the body 22 may include a second guidewire port.

[0080] When included, the distal extension 24 can extend from the body 22 at any suitable angle. In some cases, the distal extension 24 can extend from the body 22 at an angle relative to the central longitudinal axis of the body 22. In some embodiments, the angle can be an oblique angle such that the distal extension 24 extends from the body 22 at an angle that is non-parallel to the central longitudinal axis of the body 22 in an unconstrained state without external forces applied to bend or flex the distal extension 24. In some cases, the oblique angle can be in the range of 10d degrees to 50 degrees. In some cases, the distal extension 24 can extend distally from the body 22 toward a circumferential side of the body 22 opposite the guidewire port 54.

[0081] Distal extension 24 can be a thin, elongated, and flexible member, particularly relative to body 22. For example, the length of distal extension 24 can be two to ten times the length of body 22. In some embodiments, electrodes 30-36 and / or other electrodes can be disposed near distal end 24b of distal extension 24, or can be dispersed along the length of distal extension 24 (e.g., longitudinally spaced apart from each other), such as Figure 2 As shown. Other arrangements and / or configurations of electrodes on distal extension 24 are also contemplated and may be utilized. In one exemplary arrangement, each electrode may be a ring electrode, and electrode 36 (e.g., a distal ring electrode) may be disposed on distal extension 24 near the distal end of distal extension 24, electrode 34 (e.g., a third proximal ring electrode) may be proximally spaced from electrode 36 by forty (40) millimeters, electrode 32 (e.g., a second proximal ring electrode) may be proximally spaced from electrode 34 by ten (10) millimeters, and electrode 30 (e.g., a first proximal ring electrode) may be proximally spaced from electrode 32 by ten (10) millimeters. When distal extension 24 is inserted into great cardiac vein 17 or other blood vessel, this configuration of electrodes 30-36 may be aligned with left atrium 12 to allow leadless cardiac pacing device 20 to sense and / or pace left atrium 12 of heart 10. In some instances, distal extension 24 may be biased to form a shape such as a spiral coil or one or more loops.

[0082] Figure 3 Aspects of a system for implanting and / or retrieving a leadless cardiac pacing device 20 are shown. In some embodiments, the system may include a catheter 80 (e.g., Figure 13-20 ), the catheter having a lumen extending therethrough. In some embodiments, catheter 80 can be a delivery sheath, a retrieval sheath, or a combination thereof. In some embodiments, the system and / or selected components thereof can be referred to as an implantation and / or retrieval device for a leadless cardiac pacing device. Thus, except where apparent, any reference to a system can also apply to an implantation and / or retrieval device, and vice versa. In some embodiments, not all elements described herein are necessary for the disclosed systems to function properly. For example, in some embodiments, catheter 80 can be considered an optional element and / or feature.

[0083] The system 100 may include a first elongated shaft 104 including a lumen extending therethrough and extending distally from the proximal handle 102. The first elongated shaft 104 may be a tubular member and / or may be annular, having a wall defining a lumen extending therethrough. The first elongated shaft 104 may be slidably disposed within the lumen of the catheter 80. The proximal handle 102 may include one or more actuating elements 106 configured to deflect and / or manipulate the distal end of the first elongated shaft 104, for example, from side to side. In one exemplary configuration, movement and / or translation (e.g., longitudinal, rotational, etc.) of the one or more actuating elements 106 may vary the tensioning properties applied to the first elongated shaft 104, such as by pulling a wire or other suitable device. Other methods of manipulating the first elongated shaft 104 are also contemplated. Some suitable, but non-limiting, examples of materials for the proximal handle 102, the first elongated shaft 104, and / or the one or more actuating elements 106 are discussed below.

[0084] In some embodiments, the system 100 may include an elongated member 108 slidably disposed within the lumen of the first elongated shaft 104. Figure 3 In the embodiment, only the proximal end of the elongated member 108 is visible. The elongated member 108 can be tubular in configuration and include a lumen extending therethrough. The elongated member 108 can be sized and configured to extend distally through the proximal handle 102 and into the first elongated shaft 104. In some embodiments, the distal end of the elongated member 108 can be positioned near the distal end of the first elongated shaft 104. Because the elongated member 108 is slidable relative to the first elongated shaft 104, the precise positioning of the elongated member 108 relative to the first elongated shaft 104 can be varied as desired. In some embodiments, the elongated member 108 can serve as a reinforcement within the first elongated shaft 104. In some embodiments, the elongated member 108 can reduce and / or prevent axial collapse, shortening, sagging, and / or compression of the first elongated shaft 104 and / or another element slidably disposed within the lumen of the elongated member 108 (such as a second elongated shaft as described herein) when subjected to tension, torque, compression, or the like. In some embodiments, the elongated member 108 may have a greater strut strength and / or greater axial and / or lateral stiffness than the first elongated shaft 104 and / or another element (e.g., a second elongated shaft) slidably disposed within the elongated member 108. Some suitable, but non-limiting, examples of materials for the elongated member 108 are discussed below.

[0085] In some embodiments, the system 100 may include one or more flush ports. In one example, the system 100 may include a first flush port 110 that is fluidically connected to the proximal handle 102 and configured to flush and / or wash the lumen of the first elongated shaft 104. When the elongated member 108 is in place within the lumen of the first elongated shaft 104, the first flush port 110 may be configured to flush and / or wash between the outer surface of the elongated member 108 and the inner surface of the lumen of the first elongated shaft 104. In some embodiments, the system 100 may include a second flush port 112 that is fluidically connected to the elongated member 108 and configured to flush and / or wash the lumen of the elongated member 108. In at least some embodiments, both the first flush port 110 and the second flush port 112 may be present and / or used. In some embodiments, both the first flush port 110 and the second flush port 112 may not exist and / or not be used. Additional and / or other flush ports may be added and / or used as needed. In some embodiments, the system 100 may include a proximal port 114. In some embodiments, the proximal port 114 may be and / or include a sealing structure configured to prevent fluid communication with, and / or fluid leakage from, the interior of the proximal handle 102 and / or the lumen of the first elongated shaft 104. Some suitable, but non-limiting, examples of materials for the first flush port 110, the second flush port 112, and / or the proximal port 114 are discussed below.

[0086] The system 100 can include a second elongated shaft 116 slidably disposed within the lumen of the first elongated shaft 104 and / or the elongated member 108. In some embodiments, the second elongated shaft 116 can include a first proximal handle 118 disposed proximal to the proximal port 114 and / or the proximal handle 102. In some embodiments, the second elongated shaft 116 can include a second proximal handle 120 disposed proximal to the first proximal handle 118. In some embodiments, the second proximal handle 120 can be fixedly attached to and / or proximate to the proximal end of the second elongated shaft 116. The first proximal handle 118 can be slidable on the second elongated shaft 116 and selectively lockable to the second elongated shaft 116 at variable positions along the second elongated shaft 116 selected by a user. In some embodiments, locking the first proximal handle 118 to the second elongated shaft 116 can limit axial movement of the second elongated shaft 116 relative to the handle 102, the first elongated shaft 104, the elongated member 108, and / or the proximal port 114. For example, when the first proximal handle 118 is locked to the second elongated shaft 116, the first proximal handle 118 can contact and / or interfere with the proximal port 114 (or the proximal surface of the proximal handle 102 and / or the elongated member 108, if present), thereby preventing further distal translation of the second elongated shaft 116 relative to the handle 102, the first elongated shaft 104, the elongated member 108, and / or the proximal port 114. Additional and / or other reasons for locking the first proximal handle 118 to the second elongated shaft 116 will become apparent. In at least some embodiments, the second elongated shaft 116 can be a tubular member, such as a hypotube or other similar structure, having a lumen extending therethrough. In some embodiments, the second elongated shaft 116 can be a solid shaft or wire without any lumen disposed therein. Some suitable but non-limiting examples of materials for the second elongated shaft 116, the first proximal handle 118, and / or the second proximal handle 120 are discussed below.

[0087] The system 100 may include an end cap assembly 122 disposed at the distal end of the first elongated shaft 104. In some embodiments, the end cap assembly 122 may include an outer housing 124 fixedly attached to the distal end of the first elongated shaft 104 and an insert 126 fixed within the outer housing 124, such as Figure 3AAs shown. In some embodiments, the distal-most surface of the insert 126 is flush with the distal-most end surface of the outer housing 124. In some embodiments, the distal-most surface of the insert 126 is parallel and / or coplanar with the distal-most end surface of the outer housing 124. In some embodiments, the insert 126 may include a plurality of holes 128 extending through the insert 126. In some embodiments, the plurality of holes 128 may be oriented and / or extend generally longitudinally through the insert 126. In at least some embodiments, the plurality of holes 128 may open distally and / or through the distal-most surface of the insert 126. Some suitable but non-limiting examples of materials for the end cap assembly 122, the outer housing 124, and / or the insert 126 are discussed below.

[0088] The system 100 may include a plurality of wires 130 attached to the second elongated shaft 116 and extending distally from the end cap assembly 122. Although not explicitly shown, the plurality of wires 130 may be attached (e.g., fixedly attached, welded, bonded, etc.) to the second elongated shaft 116 at a location within the lumen of the first elongated shaft 104 and / or elongated member 108. In some embodiments, the location may be near the distal end of the first elongated shaft 104 and / or elongated member 108. In some embodiments, the location may be along a mid-portion of the first elongated shaft 104 and / or elongated member 108 (e.g., from about 1 / 4 to about 3 / 4 of the total length). Via translation and / or movement of the second elongated shaft 116 relative to the first elongated shaft 104 and / or elongated member 108, the plurality of wires 130 may move relative to the end cap assembly 122. In some embodiments, the plurality of wires 130 may be at a first location (e.g., Figure 3A ) and a second location distal to the first location (e.g., Figure 5A ) between and / or translate through the end cap assembly 122. Some suitable but non-limiting examples of materials for the plurality of wires 130 are discussed below.

[0089] The plurality of wires 130 can be configured to engage the proximal hub 38 of the leadless cardiac pacing device 20. In some embodiments, the plurality of wires 130 can form a plurality of wire loops 132 distal to and / or extending distally from the end cap assembly 122. In some embodiments, the plurality of wire loops 132 can translate between a first position and a second position distal to the first position. In some embodiments, the plurality of wire loops 132 can be configured to engage the proximal hub 38 of the leadless cardiac pacing device 20 in the first position. In some embodiments, the plurality of wire loops 132 can be configured to secure the proximal hub 38 of the leadless cardiac pacing device 20 relative to the end cap assembly 122 in the first position. In some embodiments, the plurality of wire loops 132 can be configured to secure the proximal hub 38 of the leadless cardiac pacing device 20 against the distal-most surface of the insert 126 in the first position. The plurality of apertures 128 can be configured to receive the plurality of wires 130. In some embodiments, the plurality of wires 130 can extend through the plurality of apertures 128. In some embodiments, the plurality of wires 130 can be moved and / or translated through the plurality of holes 128 via translation and / or longitudinal movement of the second elongated shaft 116 relative to the first elongated shaft 104 and / or the second proximal handle 120 relative to the first proximal handle 118. In some embodiments, when the plurality of wires 130 and / or the plurality of wire loops 132 are in the first position (e.g., Figure 3 ), the second proximal handle 120 can be spaced proximally from the first proximal handle 118. In some embodiments, the plurality of wires 130 and / or the plurality of wire loops 132 are configured to transmit rotational motion of the first elongated shaft 104 to the proximal hub 38 in a first position for implantation and / or retrieval of the leadless cardiac pacing device 20.

[0090] In at least some embodiments, the leadless cardiac pacing device 20 may be visualized and / or utilized before and / or during delivery. Figure 3A A configuration in which the proximal hub 38 of the leadless cardiac pacing device 20 is fixed relative to and / or against the end cap assembly 122 for navigation to the target site. In some embodiments, during retrieval of the leadless cardiac pacing device 20, the proximal hub 38 may be viewed and / or utilized. Figure 3A The configuration is shown in which the leadless cardiac pacing device 20 has been recaptured.

[0091] Figure 4A Shown along Figure 3A4-4 in the cross section. In some embodiments, each of the plurality of wire loops 132 may include and / or define a distal end segment 134. In some embodiments, the distal end segment 134 may extend between a pair (e.g., two) of the plurality of holes 128. In some embodiments, the distal end segment 134 may be substantially straight. In some embodiments, the distal end segment 134 may extend approximately parallel to the distal-most surface of the insert 126 and / or the distal-most end surface of the outer housing 124. In some embodiments, the distal end segment 134 may extend approximately perpendicular to the central longitudinal axis of the first elongated shaft 104 and / or the end cap assembly 122.

[0092] In some embodiments, in the first position, the plurality of wire loops 132 can include three or more intersecting distal end segments 134 that form a bounded opening 136 through which the neck 46 of the leadless cardiac pacing device 20 is received. In some embodiments, in the first position, the bounded opening 136 can have a minimum radial extent, measured perpendicular to the central longitudinal axis of the end cap assembly 122, that is greater than a maximum radial extent of the neck 46 measured perpendicular to the central longitudinal axis of the leadless cardiac pacing device 20, and the bounded opening 136 can have a maximum radial extent, measured perpendicular to the central longitudinal axis of the end cap assembly 122, that is less than a minimum radial extent of the proximal hub 38 measured perpendicular to the central longitudinal axis of the leadless cardiac pacing device 20.

[0093] In some embodiments, distal end segments of circumferentially adjacent wire loops and / or plurality of wire loops 132 cross over (e.g., cross over and / or cross over below) one another when viewed axially along the central longitudinal axis of end cap assembly 122. In some embodiments, when plurality of wires 130 and / or plurality of wire loops 132 are in the first position, circumferentially adjacent wire loops of plurality of wire loops 132 cross over (e.g., cross over and / or cross over below) one another when viewed axially along the central longitudinal axis of end cap assembly 122. In some embodiments, when plurality of wires 130 and / or plurality of wire loops 132 are in the second position, circumferentially adjacent wire loops of plurality of wire loops 132 cross over (e.g., cross over and / or cross over below) one another when viewed axially along the central longitudinal axis of end cap assembly 122.

[0094] In some embodiments, the plurality of wire loops 132 may include a first wire loop 140 passing through a first pair 142 of the plurality of holes 128. In some embodiments, the plurality of wire loops 132 may include a second wire loop 144 passing through a second pair 146 of the plurality of holes 128. In some embodiments, the plurality of wire loops 132 may include a third wire loop 148 passing through a third pair 150 of the plurality of holes 128. In some embodiments, the plurality of wire loops 132 may include a fourth wire loop 152 passing through a fourth pair 154 of the plurality of holes 128. Other configurations and / or arrangements are also contemplated.

[0095] In some embodiments, one hole in the second pair 146 of the plurality of holes 128 can be circumferentially disposed between the first pair 142 of the plurality of holes 128. In some embodiments, one hole in the third pair 150 of the plurality of holes 128 can be circumferentially disposed between the second pair 146 of the plurality of holes 128. In some embodiments, one hole in the fourth pair 154 of the plurality of holes 128 can be circumferentially disposed between the third pair 150 of the plurality of holes 128. In some embodiments, one hole in the first pair 142 of the plurality of holes 128 can be circumferentially disposed between the fourth pair 154 of the plurality of holes 128. Other configurations and / or arrangements are also contemplated.

[0096] exist Figure 4A In the example of , the plurality of wire loops 132 and / or their distal end segments 134 can form an "over-under" pattern relative to each other. In the illustrated arrangement, the first wire loop 140 passes over the fourth wire loop 152 and under the second wire loop 144, the second wire loop 144 passes over the first wire loop 140 and under the third wire loop 148, the third wire loop 148 passes over the second wire loop 144 and under the fourth wire loop 152, and the fourth wire loop 152 passes over the third wire loop 148 and under the first wire loop 140. The first wire loop 140, the second wire loop 144, the third wire loop 148, and the fourth wire loop 152 can collectively form and / or define a bounded opening 136. Figure 4AIn the example of , the proximal hub 38 includes four "lobes" or corners and has a generally square shape with scalloped sides. In some embodiments, the bounded opening 136 can be generally square. Other configurations are also contemplated. In some embodiments, the distal end segment 134 of the first wire loop 140 can be oriented generally parallel to the distal end segment 134 of the third wire loop 148. In some embodiments, the distal end segment 134 of the second wire loop 144 can be oriented generally parallel to the distal end segment 134 of the fourth wire loop 152. In some embodiments, the distal end segment 134 of the first wire loop 140 and / or the distal end segment 134 of the third wire loop 148 can be oriented generally perpendicular to the distal end segment 134 of the second wire loop 144 and / or the distal end segment 134 of the fourth wire loop 152. In some embodiments, adjacent holes of the plurality of holes 128 can be spaced apart a distance that is less than the width and / or radial extent of the proximal hub 38. As discussed herein, Figure 4A The configuration may be used during delivery of the leadless cardiac pacing device 20 and / or may be used during retrieval of the leadless cardiac pacing device 20.

[0097] Figure 4B Shown along Figure 3A An alternative configuration of the cross section taken along line 4-4 in FIG. 1 , which may be compared with the above Figure 4A The structure is basically the same, except that Figure 4B In the example of FIG, the plurality of wire loops 132 and / or their distal end segments 134 may form an "over-over" and "under-under" pattern relative to each other. In the illustrated arrangement, the first wire loop 140 passes over the fourth wire loop 152 and over the second wire loop 144, the second wire loop 144 passes under the first wire loop 140 and under the third wire loop 148, the third wire loop 148 passes over the second wire loop 144 and over the fourth wire loop 152, and the fourth wire loop 152 passes under the third wire loop 148 and under the first wire loop 140. The first wire loop 140, the second wire loop 144, the third wire loop 148, and the fourth wire loop 152 may collectively form and / or define a bounded opening 136. Figure 4B In the example of FIG, the proximal hub 38 includes four "lobes" or corners and has a generally square shape with scalloped edges. In some embodiments, the bounded opening 136 can be generally square. In some embodiments, the distal end segment 134 of the first wire loop 140 can be oriented generally parallel to the distal end segment 134 of the third wire loop 148.

[0098] In some embodiments, the distal end segment 134 of the second wire loop 144 can be oriented approximately parallel to the distal end segment 134 of the fourth wire loop 152. In some embodiments, the distal end segment 134 of the first wire loop 140 and / or the distal end segment 134 of the third wire loop 148 can be oriented approximately perpendicular to the distal end segment 134 of the second wire loop 144 and / or the distal end segment 134 of the fourth wire loop 152. In some embodiments, adjacent holes of the plurality of holes 128 can be spaced apart by a distance that is less than the width and / or radial extent of the proximal hub 38. As discussed herein, Figure 4B The configuration may be used during delivery of the leadless cardiac pacing device 20 and / or may be used during retrieval of the leadless cardiac pacing device 20.

[0099] Figure 4C Shown along Figure 3A An alternative configuration of the cross section taken along line 4-4 in FIG. 1 , which may be compared with the above Figure 4A The structure is basically the same, except that Figure 4C In the example of , there are only three wire loops and three pairs of holes 128. Figure 4C , the plurality of wire loops 132 and / or their distal end segments 134 may form an "over-under" pattern relative to each other. In the illustrated arrangement, the first wire loop 140 passes over the third wire loop 148 and under the second wire loop 144, the second wire loop 144 passes over the first wire loop 140 and under the third wire loop 148, and the third wire loop 148 passes over the second wire loop 144 and under the first wire loop 140. The first wire loop 140, the second wire loop 144, and the third wire loop 148 may together form and / or define a bounded opening 136. The proximal hub 38 includes three "lobes" or corners and has a generally triangular shape with scalloped edges. In some embodiments, the bounded opening 136 may be generally triangular. Other configurations are also contemplated. In some embodiments, adjacent holes of the plurality of holes 128 may be spaced apart a distance that is less than the width and / or radial extent of the proximal hub 38. As discussed herein, Figure 4C The configuration may be used during delivery of the leadless cardiac pacing device 20 and / or may be used during retrieval of the leadless cardiac pacing device 20.

[0100] Figure 5 and Figure 5A Shown Figure 3 and Figure 3A In some embodiments, when the plurality of wires 130 and / or the plurality of wire loops 132 are in the second position (e.g., Figure 5 ), the second proximal handle 120 can be moved closer to and / or adjacent to the first proximal handle 118. Figure 5AThe plurality of wires 130 and / or the plurality of wire loops 132 are shown in greater detail in a second position. When the plurality of wires 130 and / or the plurality of wire loops 132 are in the second position, the leadless cardiac pacing device 20 can be loaded onto an implantation and / or retrieval device for delivery and / or implantation to a target site, or the leadless cardiac pacing device 20 can be captured at a target site for retrieval and / or removal from the target site. In the second position, the plurality of wires 130 and / or the plurality of wire loops 132 can extend radially outward from the outermost perimeter of the leadless cardiac pacing device 20 and / or body 22. In the second position, the distal end segment 134 of each of the plurality of wire loops 132 can be substantially straight. In some embodiments, the distal end segment 134 can extend generally parallel to the distal-most surface of the insert 126 and / or the distal-most end surface of the outer housing 124. In some embodiments, the distal end segment 134 can extend generally perpendicular to a central longitudinal axis of the first elongated shaft 104 and / or the end cap assembly 122 .

[0101] Figure 6 is an exploded view of certain elements of system 100, e.g. Figure 3A and / or Figure 5A The end cap assembly 122 and the leadless cardiac pacing device 20 are shown. As can be seen, the end cap assembly 122 includes an outer housing 124 and an insert 126. The insert 126 can be coaxially received within the outer housing 124. In some embodiments, the insert 126 can be fixedly attached to the outer housing 124, such as by bonding, mechanical attachment, various forms of welding, or other means. In at least some embodiments, the insert 126 can be a unitary structure, such as Figure 6 Insert 126 can include a substantially flat and / or planar distal-most surface 127. Distal-most surface 127 of insert 126 can be configured to abut and / or contact a proximal surface of proximal hub 38. In at least some embodiments, end cap assembly 122, outer housing 124, and / or insert 126 can be free of any structure configured to engage and / or contact a side surface of proximal hub 38.

[0102] Figure 7 yes Figure 6126 . As described above, the insert 126 can include a plurality of holes 128 extending through the insert 126. In some embodiments, the plurality of holes 128 can be oriented and / or extend generally longitudinally through the insert 126. In some embodiments, some and / or each of the plurality of holes 128 can curve radially outward in a distal direction relative to a central longitudinal axis of the insert 126. In at least some embodiments, the plurality of holes 128 can open distally and / or through a distal-most surface 127 of the insert 126. A plurality of wires 130 (not shown) can extend through the insert 126 and / or the plurality of holes 128. Proximal portions of the plurality of wires 130 can extend proximally from the insert 126 into the first elongated shaft 104, wherein the proximal portions of the plurality of wires 130 can be fixedly attached and / or coupled to the distal end of the second elongated shaft 116.

[0103] Figure 8-9 Shown Figure 5A-7 For reference, in Figure 8 In the example shown, the plurality of wires 130 are shown in the second position. In some embodiments, the system 100 may include an end cap assembly 1322, which may be similar in many respects to the end cap assembly 122, except as expressly described herein. The end cap assembly 1322 may be disposed at the distal end of the first elongated shaft 104. In some embodiments, the end cap assembly 1322 may include an outer housing 1324 fixedly attached to the distal end of the first elongated shaft 104 and an insert 1326 fixed within the outer housing 1324, such as Figure 8 As shown. In some embodiments, the distal-most surface 1327 of the insert 1326 is flush with the distal-most end surface of the outer housing 1324. In some embodiments, the distal-most surface 1327 of the insert 1326 is parallel and / or coplanar with the distal-most end surface of the outer housing 1324. In some embodiments, the insert 1326 may include a plurality of holes 1328 extending through the insert 1326. In some embodiments, the plurality of holes 1328 may be oriented and / or extend generally longitudinally through the insert 1326. In at least some embodiments, the plurality of holes 1328 may open distally. Some suitable but non-limiting examples of materials for the end cap assembly 1322, the outer housing 1324, and / or the insert 1326 are discussed below.

[0104] In some embodiments, the insert 1326 may include a plurality of insert members 1330 (e.g., Figure 9) and / or an insert member retainer 1332. In some embodiments, the insert member retainer 1332 may include and / or define a distal-most surface 1327 of the insert 1326. In some embodiments, the insert member retainer 1332 may be disposed distally of the plurality of insert members 1330. The insert 1326 may be coaxially received within the outer housing 1324. In some embodiments, the insert 1326 may be fixedly attached to the outer housing 1324, such as by adhesive bonding, mechanical attachment, various forms of welding, or other means. The distal-most surface 1327 may be substantially flat and / or planar. The distal-most surface 1327 of the insert 1326 may be configured to abut and / or contact the proximal surface of the proximal hub 38. In at least some embodiments, the end cap assembly 1322, the outer housing 1324, the insert 1326, and / or the plurality of insert members 1330 may lack any structure configured to engage and / or contact a side surface of the proximal hub 38.

[0105] like Figure 9 As shown, each of the plurality of insert members 1330 can include at least a portion of one or more of the plurality of holes 1328 extending through the insert 1326. In some embodiments, each of the plurality of holes 1328 can have an oval cross-sectional shape. Figure 8-9 In the example of the embodiment shown in FIG. 1 , each of the plurality of holes 1328 can be configured to receive one or more of the plurality of wires 130 therein. For example, each of the plurality of holes 1328 can be sized, shaped, and / or configured to receive two of the plurality of wires 130 therein. In some embodiments, the insert member retainer 1332 can be configured to intersect and / or separate the distal opening of each hole 1328 into two apertures, each of which is configured to receive one of the plurality of wires 130 extending therethrough. When the plurality of insert members 1330 are coupled together to collectively form the insert 1326, the plurality of insert members 1330 can be coupled together along and / or at a central longitudinal axis of the insert 1326, which, in at least some embodiments, can be coaxial with a central longitudinal axis of the outer housing 1324. In some embodiments, the plurality of insert members 1330 can be fixedly attached together (e.g., adhesively bonded, welded, etc.) when assembled to form the insert 1326. However, fixed attachment between adjacent insert members 1330 is not strictly necessary in all cases.

[0106] Figure 10One of the plurality of insert members 1330 is shown in detail. In some embodiments, a plurality of holes 1328 can be oriented and / or can extend generally longitudinally through the insert 1326 and / or the plurality of insert members 1330. In some embodiments, some and / or each of the plurality of holes 1328 can be curved radially outward in a distal direction relative to a central longitudinal axis of the insert 1326. A plurality of wires 130 (not shown) can extend through the insert 1326, the plurality of insert members 1330, and / or the plurality of holes 1328. Proximal portions of the plurality of wires 130 can extend proximally from the insert 1326 into the first elongated shaft 104, wherein the proximal portions of the plurality of wires 130 can be fixedly attached and / or coupled to the distal end of the second elongated shaft 116.

[0107] Each of the plurality of insert members 1330 may include a first side 1334 and a second side 1336. In some embodiments, the first side 1334 and the second side 1336 may be oriented substantially perpendicular to each other. Other configurations are also possible. The first side 1334 may include a recess 1338 extending into the insert member 1330, and the second side 1336 may include a protrusion 1340 extending outward therefrom. When the plurality of insert members 1330 are assembled together, the protrusion 1340 may be received within the recess 1338. For example, the protrusion 1340 of the first insert member 1330 can be received within the recess 1338 of the second insert member 1330, the protrusion 1340 of the second insert member 1330 can be received within the recess 1338 of the third insert member 1330, the protrusion 1340 of the third insert member 1330 can be received within the recess 1338 of the fourth insert member 1330, and the protrusion 1340 of the fourth insert member 1330 can be received within the recess 1338 of the first insert member 1330. In at least some embodiments, each of the plurality of insert members 1330 can include a distal recess extending proximally from a distal-facing surface of the insert member 1330 and configured to receive a portion of the insert member retainer 1332. In some embodiments, when the end cap assembly 1322 is fully assembled, the distal-facing surface of the insert member 1330 can be substantially parallel to and / or coplanar with the distal-most surface 1327 of the insert member retainer 1332. Figure 10 As can be seen and / or determined, each of the plurality of insert members 1330 can include extending therethrough approximately half of each of the plurality of holes 1328. Thus, two adjacent insert members 1330 can be assembled together to form a complete hole in each of the plurality of holes 1328.

[0108] Figure 11Aspects of another alternative configuration of the end cap assembly 122 are shown. In some embodiments, the system 100 may include an end cap assembly 1422, which may be similar in many respects to the end cap assembly 122, except as expressly described herein. The end cap assembly 1422 may be disposed at the distal end (not shown) of the first elongated shaft 104. In some embodiments, the end cap assembly 1422 may include an outer housing 1424 fixedly attached to the distal end of the first elongated shaft 104 and an insert 1426 fixed within the outer housing 1424. In some embodiments, the distal-most surface 1427 of the insert 1426 is flush with the distal-most end surface of the outer housing 1424. In some embodiments, the distal-most surface 1427 of the insert 1426 is parallel and / or coplanar with the distal-most end surface of the outer housing 1424. In some embodiments, the insert 1426 may include a plurality of apertures 1428 extending through the insert 1426. In some embodiments, the plurality of apertures 1428 may be oriented and / or extend generally longitudinally through the insert 1426. In at least some embodiments, the plurality of apertures 1428 can open distally. In some embodiments, the outer housing 1424 can include a pair of distally extending extensions 1430. The pair of distally extending extensions 1430 can be configured to engage and / or abut one or more side surfaces of the proximal hub 38 to facilitate transferring rotational motion from the first elongated shaft 104 to the proximal hub 38. Some suitable, but non-limiting, examples of materials for the end cap assembly 1422, the outer housing 1424, and / or the insert 1426 are discussed below.

[0109] Figure 12-20 An exemplary use (e.g., implantation and retrieval) of system 100 and leadless cardiac pacing device 20 within heart 10 is described. Although the depicted method includes accessing a patient's heart 10 via the inferior vena cava, access to heart 10 may also or alternatively be via the superior vena cava and / or other routes. Figure 12-20 The view of the center 10 is similar to Figure 1 The view shown in . Figure 12-20 The dashed lines depicted in the figure depict features that may be covered by one or more other features and are generally not visible from the depicted view. The features shown in dashed lines help to describe the disclosed concepts. In addition, for clarity, features within the coronary sinus 15 are depicted in solid lines, even though these features are generally not visible from the depicted view.

[0110] In some embodiments, implanting a leadless cardiac pacing device 20 within the heart 10 may begin by positioning a guide wire within the heart 10, such as Figure 12The first guide wire 94 is shown. The first guide wire 94 can have a diameter of 0.035 inches (0.889 mm) and / or can have one or more other suitable diameters for accessing the heart 10. The first guide wire 94 can be passed into the heart 10 through an opening in the patient's skin extending into an artery or vein (e.g., a femoral vein or other blood vessel) that has been opened with a dilating feature (e.g., using a Figure 13 The catheter 80 and dilator 86 are shown and the first guide wire 94 is advanced into and / or through the inferior vena cava or other subject blood vessel by an introducer or other device for dilating the same.

[0111] In some cases, the first guide wire 94 may have one or more radiopaque markers disposed on and / or adjacent to the distal end of the first guide wire 94. Such radiopaque markers may allow the first guide wire 94 to be more easily observed by one or more medical imaging systems when the first guide wire 94 is deployed into position in the heart 10. In some embodiments, the radiopaque markers may be spaced apart from each other by a known distance. In these embodiments, by counting the number of radiopaque markers between two features within the heart 10, the distance between the two features may be determined. In some embodiments, the leadless cardiac pacing device 20 may be manufactured in various sizes, or various portions of the leadless cardiac pacing device 20, such as the body 22 and the distal extension 24, may be manufactured in various sizes and lengths. As Figure 12 As shown, by determining the distances between different features of the patient's heart 10 , such as the distance between the coronary sinus ostium 16 and the septum 18 in the right atrium 11 , the appropriate size of body 22 or distal extension 24 may be selected for a particular patient.

[0112] After measuring the distances between various features of the heart 10, or in embodiments where such measurements are not required, the catheter 80 (e.g., an introducer) and dilator 86 may be deployed into the heart 10 over the first guide wire 94, as shown. Figure 13As shown. In some cases, catheter 80 may be steerable, and dilator 86 may be located at or near the distal end of catheter 80 (e.g., at or near the distal tip). Dilator 86 may be configured to engage the ostium 16 of the coronary sinus 15 and dilate the coronary sinus 15 and / or insert a cannula into the coronary sinus 15, so that catheter 80 and / or leadless cardiac pacing device 20 can be received therein. Alternatively or additionally, catheter 80 may have a pre-shaped bend at or near the distal end of catheter 80. In this case, dilator 86 can be inserted through the distal end of catheter 80 to straighten the distal end of catheter 80 during insertion of the catheter into heart 10. Then, when the distal end of catheter 80 is within the heart, such as within the right atrium 11, dilator 86 can be withdrawn, causing the distal end of catheter 80 to bend to face toward and / or extend into the coronary sinus 15 and / or guide first guidewire 94 toward and / or into the coronary sinus 15.

[0113] Figure 14 Catheter 80 and first guidewire 94 are depicted being bent and inserted into coronary sinus 15 after dilator 86 has been moved relative to, through, and / or withdrawn from catheter 80. In some instances, after catheter 80 is bent toward coronary sinus 15, first guidewire 94 may be advanced into coronary sinus 15, and catheter 80 may be advanced along first guidewire 94 and into coronary sinus 15.

[0114] The dilator 86 can include a tapered tip, such that the catheter 80 and dilator 86 are advanced into the coronary sinus 15 to expand the inner diameter of the coronary sinus 15. In another example, the dilator 86 can be rounded or can have a tapered portion that is steeper than a tapered portion. Other dilator configurations are contemplated, and any configuration suitable for dilating the coronary sinus 15 can be used. Thus, if the coronary sinus 15 requires dilation to receive a leadless cardiac pacing device 20, the distal end or distal tip of the catheter 80 and / or dilator 86 can be advanced through the ostium 16 of the coronary sinus 15 to dilate the coronary sinus 15 an appropriate amount sufficient to receive the leadless cardiac pacing device 20. In addition to, or as an alternative to, the catheter 80 and / or dilator 86, one or more other catheters, dilators, or introducers can be used to facilitate dilation, cannulation, and / or other access to the coronary sinus 15.

[0115] Once the coronary sinus 15 has been cannulated and the catheter 80 has been inserted therein, the first guide wire 94 may then be removed from the catheter 80, as shown. Figure 15 In some cases, the second guide wire 96 can be inserted into and / or passed through the catheter 80 and deployed through the coronary sinus 15 into the great cardiac vein 17 or other blood vessels extending from the coronary sinus 15, such as Figure 16As shown. Second guide wire 96 can have a diameter of approximately 0.014 inches (0.356 mm) and / or other suitable diameters for navigating blood vessels of heart 10 and / or extending around the heart (e.g., for navigating the great cardiac vein 17 and / or other blood vessels extending from or to the great cardiac vein 17). In at least some embodiments, the diameter of second guide wire 96 can be smaller than the diameter of first guide wire 94. Optionally, in some embodiments, first guide wire 94 can be advanced through coronary sinus 15 and into the great cardiac vein 17 or other blood vessels extending from coronary sinus 15.

[0116] Figure 17 A catheter 80 and system 100 are depicted, including a leadless cardiac pacing device 20 positioned within the coronary sinus 15, with the distal extension 24 tracked over a second guidewire 96 into the great cardiac vein 17 or other cardiac vessel. The second guidewire 96 can exit a guidewire port in the body 22 and extend along the exterior of the body 22. In some embodiments, the proximal end of the body 22 of the leadless cardiac pacing device 20 and the proximal hub 38 can extend proximally out of the coronary sinus 15 into the right atrium 11, with a plurality of wires 130 engaged with the proximal hub 38. The leadless cardiac pacing device 20 can be advanced to this position by pushing the system 100, including the leadless cardiac pacing device 20, through the catheter 80 and over the second guidewire 96, with the plurality of wires 130 engaged with the proximal hub 38. Alternatively, only one of the catheter 80 or the second guidewire 96 can be used to position the system 100 and / or the leadless cardiac pacing device 20. Furthermore, it is contemplated that the leadless cardiac pacing device 20 is positioned without the use of either the catheter 80 or the second guide wire 96 .

[0117] Once the system 100, the leadless cardiac pacing device 20, and / or the catheter 80 have been positioned within the coronary sinus 15 proximate the target location, the system 100, the first elongated shaft 104, and / or the leadless cardiac pacing device 20 can be rotated to position the distal end 57 of the fixation member 50 in a desired location for piercing and engaging tissue of the heart 10 and / or the coronary sinus 15. The orientation of the leadless cardiac pacing device 20 within the coronary sinus 15 and / or within the system 100 can be adjusted by interacting with the proximal end of the system 100 and / or can be adjusted in various suitable ways. In some instances, the orientation of the leadless cardiac pacing device 20 within the coronary sinus 15 and / or within the system 100 can be adjusted by adjusting the position of the leadless cardiac pacing device 20 in a longitudinal direction using the system 100 and / or aspects thereof and / or by rotating the leadless cardiac pacing device 20 in the direction of arrow A and / or arrow B.

[0118] In some cases, the rotational and / or longitudinal position of distal tip 57 may be known or identifiable from one or more radiopaque markers, and the known rotational and / or longitudinal position may be used to position distal tip 57. In one example, distal tip 57 may be or include a radiopaque marker identifiable by one or more imaging systems to facilitate proper alignment of distal tip 57 of fixation member 50 with tissue of heart 10 and / or coronary sinus 15. Alternatively or additionally, fixation member 50 may include one or more other radiopaque features and / or leadless cardiac pacing device 20 may include one or more radiopaque markers having a known relationship to distal tip 57, which may be used to position distal tip 57 in a desired position. In one example, distal tip 57 may have a first circumferential position, and the trailing portion of fixation member 50 may have a second circumferential position oriented at a predetermined angle to the first circumferential position, which may be used to facilitate rotational alignment of distal tip 57 with target tissue of the heart. While distal tip 57 remains within the lumen of catheter 80 to prevent inadvertent penetration of distal tip 57 into tissue, rotation of leadless cardiac pacing device 20 may be performed to rotationally align distal tip 57 with target tissue of the heart, and thereafter fixation member 50 may be deployed out of the distal end of catheter 80. Alternatively or additionally, after deploying distal tip 57 of fixation member 50 out of the distal end of catheter 80, leadless cardiac pacing device 20 may be rotated in the opposite direction of the helical anchor of fixation member 50 to prevent inadvertent penetration of distal tip 57 into tissue.

[0119] Once the leadless cardiac pacing device 20 is in place, the catheter 80 and the second guide wire 96 can be retracted, and the leadless cardiac pacing device 20 can be further rotated using the first elongated shaft 104 (e.g., in the direction of arrow A and / or other suitable directions) so that the distal tip 57 and the fixation member 50 engage tissue of the heart 10 and / or the coronary sinus 15. In some instances, the leadless cardiac pacing device 20 can be oriented so that the distal tip 57 initially penetrates the left atrial myocardium and / or through the wall of the coronary sinus 15. Once the fixation member 50 engages the tissue, the system 100 (minus the leadless cardiac pacing device 20) and the catheter 80 can be retracted and optionally removed from the heart 10. Figure 18An example of how the leadless cardiac pacing device 20 may be positioned after the system 100, catheter 80, and second guide wire 96 have been retracted and the fixation member 50 has engaged tissue of the heart 10 is depicted. Although the body 22 of the leadless cardiac pacing device 20 is depicted as extending along the right atrium 11 and the left atrium 12 within the coronary sinus 15, the body 22 of the leadless cardiac pacing device 20 may be positioned within the coronary sinus 15 entirely along the right atrium 11 or entirely along the left atrium 12. In some cases, the body 22 of the leadless cardiac pacing device 20 may be positioned along the right atrium 11 and the left atrium 12 such that at least a portion of the first electrode 26 contacts tissue of the right atrium 11 and at least a portion of the second electrode 28 contacts tissue of the left atrium 12. In this case, because the electrodes are bipolar, the leadless cardiac pacing device 20 can be programmed to sense and / or pace one or more of the right atrium 11 and the left atrium 12 using the corresponding electrodes 26, 28, or other electrodes.

[0120] In some instances, the implanted leadless cardiac pacing device 20 may be removed from the coronary sinus 15 and / or the positioning of the implanted leadless cardiac pacing device 20 may be adjusted. Figure 19 A catheter 80 and a retrieval device 78 (e.g., an implant and / or retrieval device, which may or may not be the system 100 or similar to the system 100) are depicted inserted into the coronary sinus 15, with the retrieval device 78 (e.g., the end cap assembly 122 and / or the plurality of wires 130 of the system 100) engaging the proximal hub 38 of the leadless cardiac pacing device 20. Once the retrieval device 78 (e.g., the end cap assembly 122 and / or the plurality of wires 130 of the system 100) has engaged the proximal hub 38 of the leadless cardiac pacing device 20, the retrieval device 78 (e.g., the system 100) can apply a force to the leadless cardiac pacing device to cause the leadless cardiac pacing device 20 to rotate in the direction of arrow B or other suitable direction. The rotation of the leadless cardiac pacing device 20 can cause the fixation member 50 to at least partially withdraw from engagement with tissue of the heart 10.

[0121] In addition to or as an alternative to rotating the leadless cardiac pacing device 20 in the direction of arrow B, a longitudinal and / or axial force can be applied to the leadless cardiac pacing device 20 in the direction of arrow C (e.g., in the longitudinal direction). While the fixation member 50 remains engaged with tissue of the heart, applying the longitudinal and / or axial force to the leadless cardiac pacing device 20 in the longitudinal direction of arrow C can cause the fixation member 50 to elongate (e.g., straighten and / or elongate in one or more other suitable manners), such as Figure 191. The embodiment of the present invention is shown in FIG. 1 and facilitates removal of fixation member 50 from tissue of heart 10. Depending on the material configuration used, an axial force in the range of approximately 0.1-1.0 pounds-force (lbf), in the range of approximately 0.1-0.5 lbf, at least approximately 0.25 lbf, at least approximately 0.50 lbf, at least approximately 0.25 lbf but less than approximately 1.0 lbf, and / or other suitable amounts of force may be used to elongate fixation member 50. In some cases, fixation member 50 may be plastically deformed into a straightened configuration for removal from tissue of heart 10 by applying a longitudinal and / or axial force in the direction of arrow C.

[0122] like Figure 20 As shown, after the fixation member 50 has been completely removed from the tissue of the heart 10, the catheter 80 can be advanced over a portion or all of the leadless cardiac pacing device 20 via relative movement of the retrieval device 78 (e.g., system 100) and the catheter 80. Once covered by the catheter 80, the leadless cardiac pacing device 20 can be completely withdrawn from the coronary sinus 15 and the patient's heart 10 by applying further force in direction C and / or by retracting the leadless cardiac pacing device 20 in direction A (e.g., Figure 17-18 ) applies a rotational force to re-engage the fixation member 50 with tissue adjacent to the coronary sinus 15 and thereby reposition it within the coronary sinus 15 and / or a blood vessel in communication with the coronary sinus 15 (e.g., to improve positioning of electrodes of the leadless cardiac pacemaker device 20 and / or for one or more other suitable reasons).

[0123] In some cases, a catheter 80 can be inserted into the patient's vasculature (e.g., into the coronary sinus 15) and positioned over at least a portion of the leadless cardiac pacing device 20 and / or a retrieval device 78 (e.g., system 100) to facilitate withdrawal of the leadless cardiac pacing device 20 from the coronary sinus 15. In such cases, the catheter 80 can be positioned at a location covering the proximal end of the leadless cardiac pacing device 20, and the retrieval device 78 (e.g., system 100) can be advanced through the catheter 80 to the leadless cardiac pacing device 20, which is at least partially covered by the catheter 80. Positioning the catheter 80 over the proximal end of the leadless cardiac pacing device 20 can include deflecting a distal portion of the catheter 80 into the coronary sinus 15 and steering the catheter 80 over the proximal end of the leadless cardiac pacing device 20. Deflection and steering of the catheter 80 can be achieved by manipulating one or more control features adjacent to the proximal end of the catheter 80, and / or the catheter 80 can have a pre-shaped bend configured to bend toward the coronary sinus 15. In some embodiments, the leadless cardiac pacing device 20 can be removed using only the retrieval device 78 (eg, the system 100 ) in the absence of the catheter 80 .

[0124] Those skilled in the art will recognize that the present disclosure may be embodied in a variety of forms in addition to the specific embodiments described and contemplated herein. For example, as described herein, various embodiments include one or more modules described as performing various functions. However, other embodiments may include additional modules that split the described functions into more modules than described herein. Additionally, other embodiments may combine the described functions into fewer modules.

[0125] The materials of the various components and various elements thereof that can be used for the (multiple) systems disclosed herein may include materials commonly associated with medical devices. For simplicity, the following discussion relates to the system. However, this is not intended to limit the devices and methods described herein, as the discussion can be applied to other elements, components, parts or devices disclosed herein, such as but not limited to the first elongated shaft, the second elongated shaft, the end cap assembly, the outer housing, the insert, the plurality of wires, the leadless cardiac pacing device, (multiple) handles and / or their elements or parts.

[0126] In some embodiments, the system and / or its components may be made of metals, metal alloys, polymers (some examples of which are disclosed below), metal-polymer composites, ceramics, combinations thereof, and the like, or other suitable materials.

[0127] Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, available, for example, from DuPont), ), polyether block esters, polyurethanes (e.g., polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyether esters (e.g., available from DSM Engineering Plastics), ), ether or ester based copolymers (e.g., butene / poly(alkylene ether) phthalate and / or other polyester elastomers such as those available from DuPont ), polyamides (e.g., available from Bayer) Or available from Elf Atochem ), elastic polyamides, block polyamide / ethers, polyether block amides (e.g. available under the trade name PEBA obtained under the conditions of PEBA), ethylene vinyl acetate copolymer (EVA), silicone, polyethylene (PE), Marlex high-density polyethylene, Marlex low-density polyethylene, linear low-density polyethylene (e.g., ), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polypropylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyparaphenylene terephthalamide (e.g., ), polysulfone, nylon, nylon-12 (e.g., available from EMS American Grilon) ), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy resins, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (e.g., SIBS and / or SIBS50A), polycarbonate, polyurethane-silicon copolymer (e.g., from Aortech Biomaterials), or from AdvantSource Biomaterials ), biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers, polymer / metal composites, etc. thereof. In some embodiments, the sheath can be mixed with a liquid crystal polymer (LCP). For example, the mixture can contain up to about 6 percent LCP.

[0128] Some examples of suitable metals and metal alloys include stainless steels, such as 304V, 304L, and 316LV stainless steel; low carbon steel; nickel titanium alloys, such as linear elastic and / or superelastic nitinol; other nickel alloys, such as nickel chromium molybdenum alloys (e.g., UNS: N06625, such as 625, UNS: N06022, for example UNS: N10276, such as other alloys, etc.), nickel-copper alloys (such as UNS: N04400, 400, 400, 400, etc.), nickel-cobalt-chromium-molybdenum alloys (such as UNS: R30035, such as MP35- etc.), nickel-molybdenum alloys (such as UNS: N10665, for example alloy ), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys, cobalt-chromium-molybdenum alloys (such as UNS: R30003, such as platinum-rich stainless steel; titanium; platinum; palladium; gold; combinations thereof; or any other suitable material.

[0129] In at least some embodiments, part or all of the system, and / or its components may also be doped with, made of, or otherwise include radiopaque materials. Radiopaque materials are understood to be materials that are capable of producing a relatively bright image on a fluoroscopic screen or other imaging technology during a medical procedure. This relatively bright image helps the user of the system determine its position. Some examples of radiopaque materials may include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloys, polymer materials loaded with radiopaque fillers, and the like. Additionally, other radiopaque marker bands and / or coils may also be incorporated into the design of the system to achieve the same results.

[0130] In some embodiments, a degree of magnetic resonance imaging (MRI) compatibility is imparted to the systems and / or other elements disclosed herein. For example, the system and / or its components or portions can be made of materials that do not substantially distort the image and produce a large number of artifacts (i.e., gaps in the image). For example, certain ferromagnetic materials may not be suitable because they may produce artifacts in the MRI image. The system or portions thereof can also be made of materials that can be imaged by MRI machines. Some materials that exhibit these properties include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, such as etc.), nickel-cobalt-chromium-molybdenum alloys (such as UNS: R30035 such as MP35- etc.), Nitinol and similar materials, and others.

[0131] In some embodiments, the system and / or other components can include and / or be treated with a suitable therapeutic agent. Some examples of suitable therapeutic agents can include antithrombotic agents (such as heparin, heparin derivatives, urokinase, and PPack (D-phenylalanine proline arginine chloromethyl ketone)); antiproliferative agents (such as enoxaparin, angiopeptide, monoclonal antibodies capable of blocking smooth muscle cell proliferation, hirudin, and acetylsalicylic acid); anti-inflammatory agents (such as dexamethasone, prednisolone, corticosterone, budesonide, estrogen, sulfasalazine, and mesalamine); antitumor / antiproliferative / antimitotic drugs (such as paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine, epothilones, endostatin, angiostatin, and thymidine kinase inhibitors); anesthetics (such as lidocaine, bupivacaine, and ropivacaine); anticoagulants (such as D-Phe-Pro- Arg chloromethyl ketone, compounds containing RGD peptides, heparin, antithrombin compounds, platelet receptor antagonists, antithrombin antibodies, antiplatelet receptor antibodies, aspirin, prostaglandin inhibitors, platelet inhibitors and tick antiplatelet peptides); vascular cell growth promoters (such as growth factor inhibitors, growth factor receptor antagonists, transcription activators and translation promoters); vascular cell growth inhibitors (such as growth factor inhibitors, growth factor receptor antagonists, transcription inhibitors, translation inhibitors, replication inhibitors, inhibitory antibodies, antibodies to growth factors, bifunctional molecules composed of growth factors and cytotoxins, bifunctional molecules composed of antibodies and cytotoxins); cholesterol-lowering agents; vasodilators; and drugs that interfere with endogenous vasoactive mechanisms.

[0132] It should be understood that this disclosure is in many respects illustrative only. Changes may be made in detail, particularly in shape, size, and arrangement of steps, without departing from the scope of the invention. To the extent appropriate, this may include adapting any feature of an exemplary embodiment for use in other embodiments. Of course, the scope of the invention is defined in the language of the appended claims.

Claims

1. A device for implanting and / or retrieving a leadless cardiac pacemaker, comprising: a first elongated shaft comprising a lumen; a second elongated shaft slidably disposed within the lumen of the first elongated shaft; an end cap assembly fixedly attached to the distal end of the first elongated shaft; and a plurality of wires attached to the second elongated shaft and extending distally from the end cap assembly, the plurality of wires being movable relative to the end cap assembly; wherein the plurality of wires are configured to engage a proximal hub of the leadless cardiac pacing device; wherein the plurality of wires form a plurality of wire loops extending distally from the end cap assembly, wherein the end cap assembly comprises an outer shell and an insert fixed in the outer shell, and Wherein, the insert includes a plurality of holes extending therethrough, wherein the plurality of holes are configured to receive the plurality of wires.

2. The implantation and / or retrieval device according to claim 1, wherein: The outer housing is fixedly attached to the distal end of the first elongated shaft.

3. The implantation and / or retrieval device according to claim 1, wherein: The distal-most surface of the insert is flush with the distal-most end surface of the outer housing.

4. The implantation and / or retrieval device according to claim 1, wherein: Each of the plurality of apertures curves radially outward in a distal direction.

5. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: The insert is an integral structure.

6. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: The insert includes a plurality of insert members, each insert member including at least a portion of one or more of a plurality of apertures extending through the insert member.

7. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: Each of the plurality of holes is configured to receive more than one wire of the plurality of wires.

8. The implantation and / or retrieval device according to claim 2, wherein: The plurality of wire loops are configured to secure a proximal hub of the leadless cardiac pacing device against a distal-most surface of the inserter in a first position.

9. The implantation and / or retrieval device according to claim 8, wherein: The plurality of wires are configured to transmit rotational motion of the first elongated shaft to the proximal hub in a first position.

10. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: The plurality of wire loops include: a first wire loop passing through a first pair of holes in the plurality of holes; a second wire loop passing through a second pair of holes in the plurality of holes; and A third wire loop is passed through a third pair of holes in the plurality of holes.

11. The implantation and / or retrieval device according to claim 10, wherein: a hole in a second pair of holes in the plurality of holes disposed circumferentially between the first pair of holes in the plurality of holes; and One of the third pair of holes in the plurality of holes is circumferentially disposed between the second pair of holes in the plurality of holes.

12. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: The end cap assembly is free of any structure configured to engage a side surface of the proximal hub.

13. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: In a first position, the plurality of wire loops are configured to collectively surround a neck portion of the leadless cardiac pacing device extending axially from the body to the proximal hub; as well as In the second position, the plurality of wire loops are configured to extend radially outward from a perimeter of the body of the leadless cardiac pacing device.

14. The implantation and / or retrieval device according to any one of claims 1 to 4, wherein: When viewed in the axial direction, circumferentially adjacent wire rings among the plurality of wire rings cross each other.

Images