Patent Publication Number: US-2021170083-A1

Title: Implantable medical device including cable fastener

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/943,449, filed Dec. 4, 2019, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     This disclosure generally relates to various embodiments of an implantable medical device that includes a cable and a cable fastener. 
     BACKGROUND 
     Various types of implantable medical devices can include a cable that extends between two or more components of the device to provide electrical energy and communication pathways between such components. These implantable medical devices can also include one or more components of a Transcutaneous Energy Transfer (TET) System. Such systems can be used to charge one or more batteries of an implantable medical device that is implanted internally within a human body. For example, a magnetic field generated by a transmitting coil outside the body can transmit power across a cutaneous (skin) barrier to a magnetic receiving coil implanted within the body. The receiving coil can transfer the received power to an implanted pump or other internal component or components and to one or more batteries implanted within the body to charge the battery. 
     Such systems can efficiently generate and wirelessly transmit a sufficient amount of energy to power one or more components of an implantable medical device while maintaining the system&#39;s efficiency and overall convenience of use. 
     SUMMARY 
     The techniques of this disclosure generally relate to various embodiments of an implantable medical device that includes a cable and a cable fastener. The implantable medical device can be any suitable device that includes a cable that is electrically connected to one or more electronic components disposed within a housing of the device. The cable can extend through a port disposed in the housing. A portion of the cable can be adapted to be removably connected to the housing adjacent an outer surface of the housing by the fastener such that the portion of the cable extends along at least a portion of a perimeter of the housing when the cable is removably connected to the housing by the fastener. 
     In one example, aspects of this disclosure relate to an implantable medical device that includes a housing having a first major surface, a second major surface, a sidewall that extends between the first major surface and the second major surface, and a port disposed in the sidewall. The sidewall defines a perimeter of the housing. The device further includes an electronic component disposed within the housing, and a cable electrically connected to the electronic component disposed within the housing, where the cable extends through the port. A portion of the cable is adapted to be removably connected to the housing adjacent an outer surface of the sidewall by a fastener such that the portion of the cable extends along at least a portion of the perimeter of the housing when the portion of the cable is removably connected to the housing. 
     In another example, aspects of this disclosure relate to a wireless energy transfer system that includes an implantable medical device. The implantable medical device includes a housing having a first major surface, a second major surface, a sidewall that extends between the first major surface and the second major surface, and a port disposed in the sidewall. The sidewall defines a perimeter of the housing. The device further includes an electronic component disposed within the housing, and a cable electrically connected to the electronic component disposed within the housing, where the cable extends through the port. A portion of the cable is adapted to be removably connected to the housing adjacent an outer surface of the sidewall by a fastener such that the portion of the cable extends along at least a portion of the perimeter of the housing when the portion of the cable is removably connected to the housing. 
     In another example, aspects of this disclosure relate to a method that includes disposing an implantable medical device within a body of a patient, and determining a desired length of a cable of the implantable medical device. The cable is electrically connected to an electronic component disposed within a housing of the implantable medical device and extends through a port disposed in a sidewall of the device. The method further includes removably connecting a portion of the cable to the housing adjacent an outer surface of the sidewall utilizing a fastener such that the portion of the cable extends along at least a portion of a perimeter of the housing, where the perimeter of the housing is defined by the sidewall. 
     The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of one embodiment of an implantable medical device. 
         FIG. 2  is a perspective view of a housing of the implantable medical device of  FIG. 1 . 
         FIG. 3  is a schematic cross-section view of the implantable medical device of  FIG. 1 . 
         FIG. 4  is a perspective view of another embodiment of an implantable medical device. 
         FIG. 5  is a schematic cross-section view of the implantable medical device of  FIG. 4 . 
         FIG. 6  is a schematic cross-section view of a portion of a resilient gasket of the implantable medical device of  FIG. 4 . 
         FIG. 7  is a perspective view of another embodiment of an implantable medical device. 
         FIG. 8  is a schematic cross-section view of the implantable medical device of  FIG. 7 . 
         FIG. 9  is a schematic top plan view of the implantable medical device of  FIG. 7 . 
         FIG. 10  is a schematic cross-section view of a portion of the implantable medical device of  FIG. 7 . 
         FIG. 11  is a schematic cross-section view of a portion of the implantable medical device of  FIG. 7 . 
         FIG. 12  is a schematic cross-section view of a portion of the implantable medical device of  FIG. 7 . 
         FIG. 13  is a schematic cross-section view of a portion of the implantable medical device of  FIG. 7 . 
         FIG. 14  is a schematic front view of external components of a wireless energy transfer system. 
         FIG. 15  is a schematic front view of an implantable medical device of the wireless energy transfer system of  FIG. 14  disposed within a body of a patient. 
         FIG. 16  is a flowchart of one method of implanting the implantable medical device of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     In general, the present disclosure provides various embodiments of an implantable medical device that includes a cable and a cable fastener. The implantable medical device can be any suitable device that includes a cable that is electrically connected to one or more electronic components disposed within a housing of the device. The cable can extend through a port disposed in the housing. A portion of the cable can be adapted to be removably connected to the housing adjacent an outer surface of the housing by the fastener such that the portion of the cable extends along at least a portion of a perimeter of the housing when the cable is removably connected to the housing by the fastener. 
     The various embodiments of implantable medical devices described herein can include any suitable medical device, e.g., a coil of an energy transfer system, a defibrillator, LVAD, neurostimulator, pacemaker, drug pump, etc. Further, the disclosed embodiments of implantable medical devices can be utilized with any suitable system or systems. For example, one or more embodiments of implantable medical devices can be utilized with a wireless energy transfer system, e.g., one or more of the systems described in U.S. Pat. No. 10,143,788 B2, entitled TRANSCUTANEOUS ENERGY TRANSFER SYSTEMS. 
     Some implantable medical devices such as charging coils for wireless energy transfer systems can include a cable that electrically connects two or more implanted components of the system. Varying lengths of the cable may, however, be required as locations of such components within the body can vary, and the physiology of each patient may be unique. For example, a cable may be a standard length; however, such length may be greater than a length needed to connect an implanted coil to an implanted electronic module. Excess length of the cable may undesirably move around within the patient or cause strain on the cable or the components connected to the cable. 
     One or more embodiments of an implantable medical devices described herein can allow a clinician to select a desired length of cable by connecting and securing at least a portion of the cable to a housing of the device with one or more fasteners. By securing a portion of the cable that is not required to connect two or more implanted components, strain relief may be provided to the cable and the connected components. Further, the one or more fasteners can hold the portion of cable in place adjacent a perimeter of the housing to prevent the cable from contacting a major surface of the housing, thereby minimizing heat transfer from the housing to the cable and vice versa, and also minimizing the additive effects of cable and housing heating, and increased contact pressure, on the surrounding tissue. 
       FIGS. 1-3  are various views of one embodiment of an implantable medical device  10 . The device  10  includes a housing  12  having a first major surface  14 , a second major surface  16 , a sidewall  18  that extends between the first major surface and the second major surface, and a port  20  disposed in the sidewall. The sidewall  18  defines a perimeter  22  of the housing  12 . The device  10  also includes an electronic component  24  disposed within the housing  12  and a cable  26  electrically connected to the electronic component inside the housing, where the cable extends through the port  20 . As is further described herein, a portion  28  of the cable  26  is adapted to be removably connected to the housing  12  adjacent an outer surface  30  of the sidewall  18  by a fastener  32  such that the portion of the cable extends along at least a portion  34  of the perimeter  22  of the housing when the cable is removably connected to the housing. 
     The housing  12  can include any suitable material or materials, e.g., silicone, ceramic, polyurethane, or metal. Further, the housing  12  can take any suitable shape or shapes and have any suitable dimensions. 
     The first and second major surfaces  14 , 16  of the housing  12  can have any suitable dimensions and take any suitable shape or shapes. In one or more embodiments, at least one of the first major surface  14  or the second major surface  16  can take a planar shape. In one or more embodiments, at least one of the first major surface  14  or the second major surface  16  can take a curved shape. 
     The sidewall  18  of the housing  12  extends between the first major surface  14  and the second major surface  16 . The sidewall  18  can have any suitable dimensions and take any suitable shape or shapes. For example, in the embodiment illustrated in  FIGS. 1-3 , the sidewall  18  takes a planar shape in a plane orthogonal to at least one of the first or second major surfaces  14 , 16 . In one or more embodiments, the sidewall  18  can take a curved shape. In one or more embodiments, the sidewall  18  can have a concave (facing away from the housing  12 ) or convex (facing toward a center  36  of the housing) shape. Further, the sidewall  18  defines the perimeter  22  of the housing  12 . In one or more embodiments, the first major surface  14  and the second major surface  16  may have curved edge portions that meet to define the sidewall  18 . In such embodiments, the sidewall  18  is defined by an edge of the housing  12  formed by these curved edge portions of the first major surface  14  and the second major surface  16 . 
     As shown in  FIGS. 1-3 , the port  20  is disposed in the sidewall  18  of the housing  12 . The port  20  can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the port  20  is adapted to allow the cable  26  to extend therethrough such that the cable can be electrically connected to the electronic component  24  disposed within the housing  12  as is shown in  FIG. 3 . Although not shown, the port  20  can include a gasket or membrane that hermetically seals the port  20  to the cable  26 . 
     Disposed within the housing  12  is the electronic component  24 . Although depicted as including one electronic component  24 , the device  10  can include any suitable number of electronic components. Further, the electronic component  24  can include any suitable component or components, e.g., a capacitors, controllers, coils, tuning capacitors, pacemakers, defibrillators, etc. In one or more embodiments, the electronic component  24  can include a coil  44  that can be utilized with a wireless energy transfer system, e.g., wireless energy transfer system  300  of  FIGS. 14-15 . The electronic component  24  can be electrically connected to the cable  26  using any suitable technique or techniques. 
     Electrically connected to the electronic component  24  is the cable  26 . The cable  26  can include any suitable material or materials, e.g., urethane, silicone, carbothane, MP35N, MP35N/silver core, etc. The cable  26  can include one or more conductors disposed within a protective sheath or covering. Such conductors can be electrically connected to the electronic device  24  using any suitable technique or techniques. The cable  26  can include any suitable number of conductors. Further, the cable  26  can have any suitable dimensions. The cable  26  can also have any suitable cross-sectional shapes, e.g., elliptical, rectangular, etc. 
     Although depicted as being connected to a single electronic component  24 , the cable  26  can be connected to two or more electronic components disposed within the housing  12  of the device  10 . Further, the cable  26  can include a connector  38  electrically connected to cable end  40 . Such connector  38  can include any suitable connector that is adapted to connect the electronic component  24  disposed within the housing  12  to any suitable component or element of the device  10 , e.g., a pump as is further described herein. 
     The cable  26  is electrically connected to the electronic component  24  disposed within the housing  12  and extends through the port  20  such that the cable exits the housing through the port. In one or more embodiments, the portion  28  of the cable  26  is adapted to be removably connected to the housing  12  adjacent the outer surface  30  of the sidewall  18 . Any suitable technique or techniques can be utilized to connect the portion  28  of the cable  26  to the housing  12 . In one or more embodiments, the portion  28  of the cable  26  can be connected to the housing  12  using a fastener  32  such that the portion of the cable extends along at least a portion  34  of the perimeter  22  of the housing  12  when the portion of the cable is removably connected to the housing. 
     The portion  28  of the cable  26  is removably connected to the housing  12  adjacent the outer surface  30  of the sidewall  18  by the fastener  32 . As used herein, the term “adjacent the outer surface of the sidewall” means that a distance between an outer surface of the cable and the outer surface of the sidewall is no greater than 10 mm. In embodiments where a portion or portions of the cable  26  are wrapped around the housing  12  more than one time, the distance between the outermost portion of the cable and the sidewall  18  will be greater than when the cable is only wrapped once around the housing. In such embodiments, a distance between an outermost surface of the cable  26  and the outer surface  30  of the sidewall  18  is no greater than 20 mm. In one or more embodiments, the portion  28  of the cable  26  is disposed such that it is in contact with the sidewall  18 . In one or more embodiments, the portion  34  of the perimeter  22  of the housing  12  along which the portion  28  of the cable  26  extends is at least 10% of the perimeter of the housing  12 . Further, in one or more embodiments, this portion  34  is at least 25% of the perimeter  22  of the housing  12 . In one or more embodiments, this portion  34  of the housing  12  can be no greater than 100%. 
     The fastener  32  can include any suitable fastening element or component that is adapted to removably connect the portion  28  of the cable  26  to the housing  12 . Although not shown, the fastener  32  can be utilized to connect the housing  12  to tissue of the patient. In one or more embodiments, the fastener  32  can include one or more sutures  33  as shown in  FIG. 2 . The fastener  32  can include any suitable number of sutures  33 . In one or more embodiments, the fastener  32  includes a plurality of sutures  33 . 
     The sutures  33  can be connected to the housing  12  using any suitable technique or techniques. In one or more embodiments, the housing  12  can include one or more openings  42  disposed in at least one of the first major surface  14  or second major surface  16  of the housing. In one or more embodiments, the housing  12  can include a plurality of openings  42 . In one or more embodiments, one or more of the openings  42  are disposed in each of the first and second major surfaces  14 ,  16  of the housing  12  such that the opening extends between the first major surface and the second major surface of the housing. Further, the openings  42  can be disposed in any suitable location in the housing  12 . In one or more embodiments, the openings  42  can be disposed adjacent the perimeter  22  of the housing. As used herein, the term “adjacent the perimeter of the housing” means that an element or component is disposed within 10 mm of the perimeter of the housing. 
     To connect the portion  28  of the cable  26  to the housing  12 , the fastener  32 , e.g., suture  33 , can be threaded through an opening  42  and wrapped around the portion of the cable. The ends of the suture  33  can be tied together such that the suture retains the cable  26 . Any suitable technique or techniques can be utilized to thread and tie the suture  33 . In one or more embodiments, two or more sutures  33  can be threaded through the same opening  42 . In one or more embodiments, each suture  33  is connected to the housing  12  through an opening  42  of the plurality of openings. Further, additional sutures or other fasteners can be utilized to anchor the housing  12  to tissue of a patient using any suitable technique or techniques. In one or more embodiments, these sutures  33  can be threaded through one or more openings  42  in the housing  12  and through tissue. 
     The device  10  can also include the coil  44  disposed in any suitable location on or within the housing  12 . The coil  44  can include any suitable material or materials and take any suitable shape or shapes. Further, the coil  44  can have any suitable dimensions and include any desired number of windings. In one or more embodiments, the coil  44  can be electrically connected to at least one of the electronic component  24  or the cable  26  using any suitable technique or techniques. 
     As mentioned herein, the fastener  32  can include any suitable element or component that is adapted to connect the portion  28  of the cable  26  to the housing  12 . For example,  FIGS. 4-6  are various views of another embodiment of an implantable medical device  100 . All of the design considerations and possibilities regarding the medical device  10  of  FIGS. 1-3  apply equally to the medical device  100  of  FIGS. 4-6 . 
     The implantable medical device  100  includes a housing  112  that has a first major surface  114  and a second major surface  116 . The housing  112  also includes a sidewall  118  that extends between the first major surface  114  and the second major surface  116 . The device  100  also includes an electronic component  124  disposed within the housing  112 , and a cable  126  electrically connected to the electronic component, wherein the cable extends through a port  120 . A portion  128  of the cable  126  is adapted to be removably connected to the housing  112  adjacent an outer surface  130  of the sidewall  118  by a fastener  132  such that the portion of the cable extends along at least a portion  134  of perimeter  122  of the housing when the portion of the cable is removably connected to the housing. 
     One difference between the implantable medical device  100  of  FIGS. 4-6  and the implantable medical device  10  of  FIGS. 1-3  is that the fastener  132  of the device  100  includes a slot  144  disposed adjacent the sidewall  118  of the housing  112 . The slot  144  is adapted to retain the portion  128  of the cable  126  that is removably connected to the housing  112 . Slot  144  can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the slot  144  can include a u-shape in a plane orthogonal to the first and second major surfaces  114 , 116  of the housing  112  as shown in  FIG. 5 . The slot  144  can retain the portion  128  of the cable  126  using any suitable technique or techniques. In one or more embodiments, the portion  128  of the cable  126  is friction-fit within the slot  144 . 
     The slot  144  can be connected to the housing  112  using any suitable technique or techniques. In one or more embodiments, the slot  144  can be disposed in the sidewall  118  of the housing  112 . Further, in one or more embodiments, a resilient gasket  146  can be disposed over the sidewall  118  of the housing  112 , where the slot  144  is disposed in the resilient gasket as is shown in  FIG. 5 . The resilient gasket  146  can be attached or connected to the sidewall  118  of the housing  112  using any suitable technique or techniques, e.g., adhering, mechanically fastening, friction fitting, etc. In one or more embodiments, the resilient gasket  146  can be molded to the sidewall  118  of the housing  112  using any suitable technique or techniques. Further, the gasket  146  can be molded as part of the housing  112  such that the gasket and housing are integral. The gasket  146  can also be overmolded onto the housing  112  using any suitable technique or techniques. The gasket  146  can be continuous or segmented such that one or more portions of the sidewall  118  do not include a portion of the gasket. 
     In one or more embodiments, the sidewall  118  of the housing  112  can include one or more features that are adapted to assist in bonding or molding the resilient gasket  146  to the sidewall. Any suitable features can be disposed on the sidewall  118  to assist in such bonding or molding of the gasket  146 . 
     The resilient gasket  146  can take any suitable shape or shapes and have any suitable dimensions. Further, the resilient gasket  146  can include any suitable material or materials, e.g., silicone, polyurethane, etc. In one or more embodiments, the resilient gasket  146  can include a reinforcing material disposed within a matrix, e.g., polyester mesh, polypropylene mesh, etc. Any suitable portion or portions of the gasket  146  can include a reinforcing material. For example, in one or more embodiments, one or both of a first tab  150  of the resilient gasket  146  and a second tab  152  of the gasket can include a reinforcing material. Further, the slot  144  of the gasket  146  can be reinforced with an eyelet that is inserted into or formed within the slot. 
     In one or more embodiments, the resilient gasket  146  includes an outer edge  148  that is adapted to deflect when engaging tissue of the patient to stabilize the device  100  within the tissue. For example, as illustrated in  FIG. 5 , the outer edge  148  of the resilient gasket  146  includes the first tab  150  and the second tab  152  disposed on each side of the slot  144 . The first and second tabs  150 ,  152  are adapted to rotate away from the slot  144  (direction  154  in  FIG. 6 ) when the outer edge  148  of the gasket  146  engages tissue of the patient. 
     The housing  112  can also include one or more openings  142  disposed in at least one of the first major surface  114  or second major surface  116  of the housing. Any suitable openings  142  can be disposed in the housing  112 , e.g., openings  42  of device  10  of  FIGS. 1-3 . In one or more embodiments, one or more the openings  142  can be disposed in at least one of the first major surface  114  or second major surface  116  of the housing  112  adjacent the perimeter  122  of the housing. Further, in one or more embodiments, one or more the openings  142  can be disposed in the resilient gasket  146  adjacent the slot  144 . As used herein, the phrase “adjacent the slot” means that the element or component is disposed closer to the slot  144  than to a center  136  of the housing  112  of the device  100  as shown in  FIG. 5 . In one or more embodiments, one or more openings  142  can be disposed through at least one of the first tab  150  or the second tab  152 . 
     The fastener  132  can also include one or more sutures  133  that can be connected to the housing  112  through one or more openings  142  to further retain the cable  126 . For example, a suture  133  can be threaded through an opening  142  at an exit  156  of the cable  126 , i.e., where the cable exits the slot  144 . Any suitable sutures  133  can be utilized, e.g., suture  33  of  FIGS. 1-3 . In one or more embodiments, the sutures  133  can provide strain relief to the cable  126  by securing it to the resilient gasket. 
     As mentioned herein, the various embodiments of fasteners are adapted to removably connect a portion of the cable to a housing of an implantable medical device. Further, one or more fasteners can be utilized to connect the housing of the device to tissue of a patient. For example,  FIGS. 7-13  are various views of another embodiment of an implantable medical device  200 . All of the design considerations and possibilities regarding the implantable medical device  10  of  FIGS. 1-3  and the implantable medical device  100  of  FIGS. 4-6  apply equally to the implantable medical device  200  of  FIGS. 7-13 . 
     The device  200  includes a housing  212  having a first major surface  214 , a second major surface  216 , and a sidewall  218  that extends between the first major surface and the second major surface. The device  200  also includes an electronic component  224  disposed within the housing  212  and a cable  226  that is electrically connected to the electronic component and extends through a port  220  that is disposed in the sidewall  218  of the housing  212 . A portion  228  of the cable  226  is adapted to be removably connected to the housing  212  adjacent an outer surface  230  of the sidewall  218  by a fastener  232  ( FIG. 9 ) such that the portion of the cable extends along at least a portion  234  of a perimeter  222  of the housing when the portion of the cable is removably connected to the housing. 
     One difference between the implantable medical device  200  of  FIGS. 7-9  and implantable medical devices  10  and  100  described herein is that a resilient substrate  260  is disposed on the second major surface  216  of the housing  212 . A portion  266  of the resilient substrate  260  is adapted to extend over the portion  228  of the cable  226  that is connected to the housing  212  and be connected to the first major surface  214  of the housing, e.g., by a fastener  232 . In one or more embodiments, the resilient substrate  260  is sized to wrap around a portion of the cable  226  to provide protection and strain relief to the cable. 
     The resilient substrate  260  can include any suitable material or materials, e.g., silicone, polyurethane, etc. In one or more embodiments, the substrate  260  can include a reinforcing layer  262  disposed on a major surface of the substrate or within the substrate as is shown in  FIG. 8 . In one or more embodiments, the reinforcing layer  262  can be disposed within a matrix  264  of the substrate  260 . The reinforcing layer  262  can include any suitable material or materials, e.g., mesh (spunbonded, woven, etc.), woven or nonwoven layers, etc. Further, the matrix  264  can include any suitable material or materials, e.g., silicone, polyurethane, etc. The reinforcing layer  262  can be disposed within the matrix  264  using any suitable technique or techniques. In one or more embodiments, reinforcing layer  262  does not extend the entire length of the second major surface  216  but can be provided adjacent the perimeter  222  where reinforcement may be of benefit, such as a cord to improve the tear strength of the reinforcing layer. 
     In one or more embodiments, the substrate  260  can be connected to the second major surface  216  of the housing  212  using any suitable technique or techniques. In one or more embodiments, the substrate  260  can be, e.g., adhered, molded, or mechanically attached to the housing  212 . 
     As mentioned herein, the portion  266  of the resilient substrate  260  can be folded or extended over the portion  228  of the cable  226  and connected to the first major surface  214  of the housing  212  by the fastener  232 . The fastener  232  can include any suitable fastener fasteners, e.g., the same fasteners described herein regarding fastener  32  of  FIG. 1-3 . As shown in  FIG. 9 , the fastener  232  includes a suture  233  that can be extended through the folded portion  266  of the substrate  260  and an opening  242  that is disposed in the housing  212  as is further described herein. Any suitable number of fasteners  232  can be utilized to connect the portion  266  of the substrate  260  to the first major surface  214  of the housing  212 . Although not shown, additional fasteners  232  can be utilized to attach additional portions of the cable  226  to the housing  212  using any suitable technique or techniques. 
       FIG. 10  illustrates one embodiment of the substrate  260  being utilized to retain the portion  228  of the cable  226 . The portion  266  of the resilient substrate  260  is wrapped over the cable  226  and held in place by a suture  233  that is threaded through opening  242  and the substrate. In one or more embodiments, the suture  233  can be wrapped around the resilient substrate  260  and the cable  226  and threaded through the substrate  260  and not the housing  212  as shown in  FIG. 11 . 
     Further, additional sutures or other fasteners can be threaded through the resilient substrate  260  to anchor the housing  212  to tissue of a patient using any suitable technique or techniques. For example, as shown in  FIG. 12 , the suture  233  is threaded through the resilient substrate  260  and tissue  270  of the patient such that the housing  212  is connected to the tissue. In one or more embodiments, the suture  233  can be threaded through the resilient substrate  260  and tissue  270  with the substrate being wrapped around the cable  226  as shown in  FIG. 13  to connect the cable  226  to the housing and the housing to the tissue  270 . 
     Another difference between the implantable medical device  200  of  FIGS. 7-13  and implantable medical devices  10  and  100  is that the housing  212  is encased in a resilient material  268 . Any suitable resilient material or materials can be utilized, e.g., silicone, polyurethane, ceramic, metal, etc. Any suitable portion or portions of the housing  212  can be encased within the resilient material  268 . In one or more embodiments, the entire housing  212  is encased within the resilient material  268 , and an opening  271  can be formed in the resilient material such that the cable  226  extends through the resilient material. 
     The various embodiments of implantable medical devices described herein can be utilized with any suitable system. For example,  FIGS. 14-15  are schematic views of one embodiment of a wireless energy transfer system  300 . The system  300  includes an implantable medical device  310  and external components  370 . In  FIG. 14 , the external components  370  of the system  300  are illustrated, and in  FIG. 15 , the implantable medical device  310  of the system is illustrated as being implanted within a body  302  of a patient  304 . The external components  370  can include an external module  372  and a primary coil  374 . In one or more embodiments, the primary coil  374  can be disposed in a separate housing  376  from the external module  372 . The external module  372  can be located in any suitable location relative to the patient&#39;s body  302 , e.g., around the patient&#39;s hip (e.g., in a pocket of the patient&#39;s clothing, mounted to a belt of the patient, etc.), and the primary coil  374  can be located in any suitable location relative to the patient&#39;s body  302 , e.g., on the patient&#39;s chest and secured in place by a garment worn by the patient, such as a sling or vest. The external module  372  and primary coil  374  are further connected to each other by a wire  378 . Also shown in  FIG. 14  is a clinical monitor  380 , which can be worn, e.g., on the patient&#39;s wrist. In other examples, the clinical monitor  380  can be located elsewhere, such as in the external module, or in the patient&#39;s smartphone, or not on the patient altogether. 
     In the embodiment illustrated in  FIG. 14 , an external battery and external electronics (not shown) can be disposed in a housing  382  of the external module  372 . In one or more embodiments, the external battery may be disposed in a separate housing (e.g., separately mounted to the outside of the patient) and wired to the external module  372 . 
     The implantable medical device  310  can include any suitable device described herein, e.g., device  10  of  FIGS. 1-3 . As illustrated in  FIG. 15 , the implantable medical device  310  can include a secondary coil  344  disposed within a housing  312 , a pump  384 , and an electronic module  386  electrically connected to the housing and the pump. In one or more embodiments, each of the housing  312 , the pump  384 , and the electronic module  386  can be disposed in a separate housing and dispersed throughout the patient&#39;s body  302  to accommodate the anatomy of the patient. For instance, in the embodiment illustrated in  FIG. 15 , the housing  312  is mounted in the patient&#39;s chest. In one or more embodiments, the housing  312  can be mounted to the patient&#39;s rib, back, abdomen, or muscle in any subcutaneous plane. 
     The housing  312  is electrically connected to the electronic module  386  by a first cable  326 , and the pump  384  is electrically connected to the electronics module  386  by a second cable  388 . The pump  384  can be connected, e.g., to a heart of the patient. Although not shown, the implantable medical device  310  can also include an implanted battery disposed in any suitable location within the patient&#39;s body  302 . In one or more embodiments, the implanted battery is disposed within a housing  390  of the electronics module  386 . In one or more embodiments, the implanted battery may be separately housed, and an additional wire may connect the electronics module  386  to the implanted battery. 
     The secondary coil  344  is disposed within the housing  312  of the implantable medical device  310  and is adapted to be electrically coupled to the primary coil  374 . For example, the secondary coil  344  can be adapted to be inductively coupled to the primary coil  374 . Positioning of the secondary coil  344  within the patient  304  can be done in such a manner that makes mounting the primary coil  374  in proximity to the secondary coil easy for the patient. For instance, the secondary coil  344  can be positioned close to the skin of the patient  304 . Moreover, the secondary coil  344  can be positioned close to a relatively flat part of the patient&#39;s body  302  to make mounting the primary coil  374  easier. In the embodiment illustrated in  FIG. 15 , the secondary coil  344  disposed within the housing  312  is positioned close to the front of the patient&#39;s chest such that mounting the primary coil  374  to the patient&#39;s chest places the primary coil proximate the secondary coil. In those examples where the housing  312  is mounted to the patient&#39;s rib, back, or abdomen, the secondary coil  344  can similarly be located close to the patient&#39;s skin, such that the primary coil  374  can be mounted in close proximity. 
     The various embodiments of implantable medical devices described herein can be implanted within a body of a patient using any suitable technique or techniques. For example,  FIG. 16  is a flowchart of one embodiment  400  of a method  400  of implanting the implantable medical device  10  of  FIGS. 1-3 . Although described in regard to medical device  10 , method  400  of  FIG. 16  can be utilized with any implantable medical device. At  402 , the implantable medical device  10  can be disposed within a body of a patient using any suitable technique or techniques. For example, an incision or incisions can be formed in any suitable portion of the body, and the implantable medical device  10  can be inserted into a cavity of the body through such incision. A desired length of the cable  26  of the implantable medical device  10  can be determined at  404 . For example, a desired length of the cable  26  can include a distance from the implantable medical device  10  to an electronic module (e.g., electronic module  386  of  FIG. 15 ) disposed within the body of the patient such that the cable  26  can electrically connect the electronic component  24  disposed within the housing  12  to the electronic module. 
     At  406 , the portion  28  of the cable  26  is removably connected to the housing  12  adjacent the outer surface  30  of the sidewall  18  utilizing the fastener  32  such that the portion of the cable extends along at least a portion  34  of the perimeter  22  of the housing and such that the cable  26  has the desired length using any suitable technique or techniques. The housing  12  can be connected to tissue of the patient at  408  using any suitable technique or techniques. 
     In one or more embodiments, the cable  26  can optionally be electrically connected to an electronic module disposed within the body of the patient using any suitable technique or techniques at  410 . In embodiments where the implantable medical device includes a pump (e.g., pump  384  of  FIG. 15 ), such pump can be electrically connected to the electronic module with a second cable (e.g., second cable  388  of  FIG. 15 ) disposed within the body of the patient at  412 . Further, in embodiments where the implantable medical device  10  is a component of a wireless energy transfer system (e.g., system  300  of  FIGS. 14-15 ), a battery disposed within the electronic module can be inductively recharged at  414  by disposing a primary coil adjacent a secondary coil disposed within the housing  12  of the implantable medical device using any suitable technique or techniques. 
     It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. It should also be understood that, depending on the example, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques). In addition, while certain aspects of this disclosure are described as being performed by a single module or unit for purposes of clarity, it should be understood that the techniques of this disclosure may be performed by a combination of units or modules associated with, for example, a medical device. 
     In one or more examples, the described techniques may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer). 
     Instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term “processor” as used herein may refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. Also, the techniques could be fully implemented in one or more circuits or logic elements.