Patent Description:
Ventricular assist devices (VAD) generally relate to systems that include a pump that assists heart function without replacing the heart in order to improve hemodynamics. Depending on the needs and demands of the patient, the pump may be placed outside the patient's body (extra- or para-corporeal devices), or within the patient's abdomen such as in the pericardial cavity beneath or above the diaphragm (intracorporeal device). Attempts have also been made to place such pumps within the patient's vasculature, including within the heart itself, as for example disclosed in <CIT>.

According to one example ("Example <NUM>"), an implantable medical device for cardiac assistance includes a main body configured to deploy within the aorta and including a lumen maintaining fluid flow through the aorta and an access site in a sidewall of the main body providing access to the lumen of the main body; and a branch member configured to deploy within the access site to fluidly connect with the lumen of the main body and including a pump configured to force blood flow through the branch member and into the lumen of the main body.

According to another example ("Example <NUM>"), further to the implantable medical device of Example <NUM>, the branch member is configured to implant within an atrium or a ventricle of a patient.

According to another example ("Example <NUM>"), further to the implantable medical device of Example <NUM>, the pump is configured to increase blood flow into the aorta for cardiac assistance.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the branch member includes a sealing element near a first end configured to engage a tissue wall of the atrium or the left ventricle.

According to another example ("Example <NUM>"), further to the implantable medical device of Example <NUM>, the sealing element comprises a polymeric material.

According to another example ("Example <NUM>"), further to the implantable medical device of Example <NUM>, the flange configured to engage the tissue wall in a fluid tight fluid communication between the branch member and the lumen of the main body.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the access site in the main body includes a fenestration and the branch member is configured to seal within the fenestration to fluidly connect the branch and the main body.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the device further includes a portal arranged within the main lumen aligned with the access site in the main body, and the branch member is configured to implant within the portal to fluidly connect the branch and the main body.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the pump is removably coupled to the branch member.

According to another example ("Example <NUM>"), further to the implantable medical device of Example <NUM>, the pump is configured to anchor within the branch member.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the branch is configured to implant within the aorta adjacent or between an aortic valve.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the pump is powered remotely.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the branch member is configured to couple the atrium and the aorta and allow independent motion of the atrium and the aorta.

According to another example ("Example <NUM>"), the implantable medical device of any one of Examples <NUM>-<NUM>, the pump is configured to deliver the blood flow through the branch member and into the lumen of the main body parallel to natural blood flow through the aorta.

The foregoing Examples are just that, and should not be read to limit or otherwise narrow the scope of the invention which is solely defined by the appended claims. The drawings and detailed description are to be regarded as illustrative in nature rather than restrictive in nature.

However, the inventive concept with an access site in a sidewall of the main body is only clearly visible in <FIG>.

Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of methods and apparatus configured to perform the intended functions. The scope of the invention is however solely defined by the appended claims. It should also be noted that the accompanying drawing figures referred to herein are not necessarily drawn to scale, but may be exaggerated to illustrate various aspects of the present disclosure, and in that regard, the drawing figures should not be construed as limiting.

Various aspects of the present disclosure are directed to systems and methods for improving or assisting the cardiac function of the heart. The disclosed systems and methods generally include an endoprosthesis having a pump within the patient's vasculature. The disclosed systems and methods also include a delivery system configured for transcatheter delivery of the pump and the branch member.

In the instant disclosure, the examples are primarily described in association with transcatheter cardiac applications involving the aorta (also referred to herein as ventricular assist), although it should be readily appreciated that the various embodiments and examples discussed herein can be applied in association with any known uses of ventricular assist devices, including for use within other regions of the heart or vasculature, as well as percutaneous procedures (e.g., laparoscopic) and / or surgical procedures. Cardiac assist devices, as discussed herein, may be beneficial for patients experiencing heart failure. The cardiac assist devices, consistent with various aspects of the present disclosure may include an implantable pump that forces or conveys blood from chambers of the heart (e.g., the right ventricle or left ventricle) to the rest of the body (e.g., via the aorta).

As shown in <FIG>, a system <NUM> according to various embodiments includes a branch member <NUM> and a pump <NUM> disposed at least partially within the branch member <NUM>, and a retention element <NUM> configured to help maintain a position of the pump <NUM> within the branch member <NUM>. The branch member <NUM> may be a branch member <NUM> that forms a part of a branched implantable medical device as discussed in further detail below.

In certain instances, the branch member <NUM> may include a graft, a stent, or a combination of a stent and a graft. As discussed in further detail below, the branch member <NUM> may be a stent-graft device that is incorporated with a stent-graft device implanted into a patient's aorta thereby forming a branched implantable medical device. The branch member <NUM> may be a branch member coupled or joined to a main stent-graft device that is implanted in the aorta. In certain instances, the branch member <NUM> and pump <NUM> may act as a right ventricular assist device and increase blood flow into the pulmonary veins or arteries. In these instances, the main body <NUM> may be placed in the pulmonary artery with the branch member <NUM> be arranged in the atrium or ventricular as discussed in detail herein.

In certain instances, the stent portion of a branch member <NUM> is defined by a plurality of interconnected strut elements. The stent portion of the branch member <NUM> may comprise, such as, but not limited to, elastically deformable metallic or polymeric biocompatible materials. The stent portion of the branch member <NUM> may comprise a shape-memory material, such as nitinol, a nickel-titanium alloy. Other materials suitable for the stent portion of the branch member <NUM> include, but are not limited to, other titanium alloys, stainless steel, cobalt-nickel alloy, polypropylene, acetyl homopolymer, acetyl copolymer, other alloys or polymers, or any other biocompatible (e.g., bio-absorbable) material having adequate physical and mechanical properties to function as the stent portion of the branch member <NUM>, as described herein. The stent portion of the branch member <NUM> may therefore be self-expanding and/or may be balloon expandable. That is, in various examples, the branch member <NUM> may be transitionable between a collapsed delivery configuration and an expanded deployed configuration.

In certain instances, the branch member <NUM> may be a stent that is partially covered with a graft material. The graft material of the branch member <NUM> may further include a graft material disposed thereabout (e.g., such as about an interior of or an exterior of the branch member <NUM>). In various embodiments, graft materials can include, for example, expanded polytetrafluoroethylene (ePTFE), polyester, polyurethane, fluoropolymers, such as perfluoroelastomers and the like, polytetrafluoroethylene, silicones, urethanes, ultra high molecular weight polyethylene, aramid fibers, and combinations thereof. Other embodiments for a graft member material can include high strength polymer fibers such as ultra-high molecular weight polyethylene fibers (e.g., Spectra®, Dyneema Purity®, etc.) or aramid fibers (e.g., Technora®, etc.). Some embodiments may comprise of a graft material only partially disposed about the branch member frame.

In certain instances, the system <NUM> is configured such that the pump <NUM> can be removably coupled with the branch member <NUM>. In some examples, the pump <NUM> is removably coupled with the branch member <NUM> after the branch member <NUM> has been delivered and deployed within the patient's vasculature (e.g., a branch member of an implantable medical device). According to some implementations, the pump <NUM> is removable from the patient's vasculature without also requiring removal of the branch member <NUM> (e.g., such that the pump <NUM> may be replaced and/or such that removal of the system <NUM> may be done minimally invasively).

The pump <NUM> is generally configured to drive or otherwise cause blood to flow across the pump <NUM> from an inflow side <NUM> of the system <NUM> to an outflow side <NUM> of the system, such as along a direction of arrow <NUM>. The pump mechanism (also referred to herein as a pump drive) of the pump <NUM> may be, for example, a centrifugal-action pump, an axial-action pump, or other similar device such as a worm-style drive mechanism, or impeller. The pump housing is configured to interface and engage with the branch member <NUM>. The pump <NUM> is situated within the deployed branch member <NUM> such that the pump <NUM> is operable to pump or drive blood across the pump <NUM> and into the aorta and out into the vasculature of the body. The pump <NUM> can be operated to draw blood from the left ventricle (or other heart chamber), blood across the pump <NUM>, and into the aorta and out through the vasculature of the body.

In certain instances, the system <NUM> further includes a driveline <NUM>. The driveline <NUM> is a cable assembly that operates to electrically couple a controller <NUM> located external to the patient's anatomy with the pump <NUM> or the driveline <NUM> can be a rotating driveshaft. The driveline <NUM> may be routed through the patient's vasculature (e.g., exiting the heart through the apex of the left ventricle) and then out through the skin to where it is coupled with the controller <NUM> or to a subcutaneously implanted controller <NUM>. The controller <NUM> is a module that is configured to control the operation of the pump <NUM>. The controller <NUM> may include a batter to control operation of the pump <NUM>.

In certain instances, the driveline <NUM> may be routed through one of the left or right subclavian arteries, veins, or the left common carotid artery to a subclavian or other associated access. Alternatively, the driveline <NUM> may be routed through the descending aorta to a femoral or other associated access. In certain instances, the driveline <NUM> is associated with the retention element <NUM>, for example being routed through the retention element <NUM> or integral to the retention element <NUM>. In some examples where the driveline <NUM> is integral with the retention element <NUM>, the retention element <NUM> includes one or more connectors such that when the retention element <NUM> is coupled to the branch member <NUM>, the driveline <NUM> is electrically coupled with the pump <NUM>.

In some embodiments, the system <NUM> may be configured to operate without the need for the driveline <NUM>, or the driveline <NUM> need not extend extracorporeally. That is, in some examples, an extracorporeal control system may be configured to both control the operation of the pump, and to power the pump wirelessly (e.g., through a transcutaneous energy transmission system). In some examples, transcutaneous energy transmission may be accomplished through known means of transcutaneous energy transmission, such as those described in <CIT>. Such a configuration eliminates the need to route the driveline <NUM> through the vasculature and out through a percutaneous access site, which can help minimize a risk for infection. In instances where the system <NUM> is arranged trans-apically, the driveline <NUM> may not exit the patient through the thoracic cavity. In some examples, the driveline <NUM> may be configured to be unplugged or decoupled from the pump <NUM> at its junction with the pump <NUM>. In some examples, decoupling the driveline <NUM> from the pump <NUM> includes decoupling or removing the retention element <NUM>. In some examples, the system <NUM> may include an "antenna" (or internal coil) that is configured for transcutaneous energy transfer ("TET"). In some examples, an extracorporeal TET component maybe worn around the torso similar to a standard heart rate monitor, and additionally coupled to a power source (wall unit or high capacity battery) such that the extracorporeal TET component is operable to transmit energy transcutaneously to the antenna.

As noted above, system <NUM> may be incorporated into a branch member configured to interface with an access site of a main body of an implantable medical device. The main body and branch member (include the system <NUM>) may be compacted or collapsed to the delivery state prior to deployment with the main body of the implantable medical device as shown in further detail below.

The system <NUM> may be used as an implantable medical device for cardiac assistance as shown in <FIG>. The system <NUM> may be included with a main body <NUM> portion of an implantable medical device or with a branch member <NUM> that is coupled or joined to the main body <NUM> as discussed in further detail below. The implantable medical device is shown implanted in a patient's aorta <NUM> leading from a patient's heart <NUM>. The patient's heart <NUM> is a simplified diagram and includes the aortic valve <NUM>, the right atrium (RA), left atrium (LA), right ventricle (RV), and left ventricle (LV).

According to the invention, the implantable medical device includes a main body <NUM> configured to deploy within the aorta <NUM>. The main body <NUM> includes a lumen maintaining fluid flow through the aorta <NUM>. In addition, the main body <NUM> also includes an access site <NUM> in a sidewall of the main body <NUM> providing access to the lumen of the main body <NUM>. The access site <NUM> may be a fenestration created before or after implantation of the main body <NUM>. In addition, the main body <NUM> may include radiopaque markers arranged near adjacent the access site <NUM> to facilitate deployment. Further, the access site <NUM> may be deployed as facing away from the brachiocephalic, subclavian, and carotid arteries. The main body <NUM> may include a curvature or conform to a curvature of the aorta with the access site <NUM> being arranged opposite the curvature and thus be arranged as facing away from the brachiocephalic, subclavian, and carotid arteries.

The implantable medical device according to the invention further includes a branch member <NUM> configured to deploy within the access site <NUM> to fluidly connect with the lumen of the main body <NUM>. The branch member <NUM> is configured to interface with and secure a pump <NUM> configured to convey (or force) blood flow through the branch member <NUM> and into the lumen of the main body <NUM>. The branch member <NUM> and pump <NUM> may include the structural and functional components described above with reference to system <NUM>. In addition and as noted above, the pump <NUM> may be configured to increase blood flow into the aorta <NUM> for cardiac assistance. In certain instances, the pump <NUM> may be integrated into the main body <NUM>. In these instances, the main body <NUM> may lack an access site <NUM> and the pump <NUM> may increase blood flow within the aorta <NUM>.

As shown in <FIG>, the branch member <NUM> extends between the aorta <NUM> and the LA (e.g., forming an anastomosis between the two structures). In certain instances, the branch member <NUM> may be configured to implant within the RA or LV and connect to the main body <NUM> in the aorta <NUM>. Implanting the branch member <NUM> in the LA may facilitate heart failure patients having preserved ejection fraction. The branch member <NUM> and main body <NUM> may function as a cardiac assist device with the pump <NUM> forcing blood from one or more chambers of the heart into the aorta <NUM>. The branch member <NUM>, main body <NUM>, and pump <NUM> may be used to assist heart function for patients' having weakened hearts or heart failure.

As noted above, to facilitate coupling of the branch member <NUM> and the main body <NUM>, the access site <NUM> of the main body <NUM> fluidly connects with the lumen of the main body <NUM>. The access site <NUM> in the main body <NUM> may include a fenestration or a portal as discussed in further detail below with reference to <FIG>. To deliver the branch member <NUM> and connect the aorta <NUM> and the LA, a puncturing device (e.g., arranged through the access site <NUM>) creates a small access site in a tissue wall of the aorta <NUM> and the LA. The branch member <NUM>, for example, may include stent-and graft components (as noted above with reference to <FIG>) that allow for flexibility and relative motion between the aorta <NUM> and the LA (or LV). In certain instances, the branch member <NUM> is configured to couple the atrium (LA OR RA) and the aorta <NUM> and allow independent motion of the atrium (LA OR RA) and the aorta <NUM>.

In addition, the branch member <NUM> and pump <NUM> combination provides direct increase of blood flow for cardiac assistance. Further, the branch member <NUM> and pump <NUM> preserves space within the LA (or LV) to facilitate natural pumping of the heart <NUM>, avoid interfering with valves of the heart <NUM>, and enable transcatheter implantation. The pump <NUM> may be configured to deliver the blood flow through the branch member <NUM> and into the lumen of the main body <NUM> parallel to natural blood flow through the aorta <NUM>. As discussed in further detail below, the branch member <NUM> and pump <NUM> may be collapsed to a delivery configuration of transcatheter delivery. Having the main body <NUM> arranged in the aorta <NUM> mitigates the risk of aortic dissection, protects the aortic wall from an increased fluid flow from the pump <NUM>, and may reduce risk of device deployment.

In addition and as noted above with reference to <FIG>, the pump <NUM> may be removably coupled to the branch member <NUM>. The pump <NUM> may be delivered with the branch member <NUM> or delivered separately after the branch member <NUM> is fluidically coupled to the main body <NUM>. The pump <NUM> may anchor within the branch member <NUM>. The pump <NUM>, for example, may have retractable anchors that extend after the pump <NUM> is forced from a delivery sheath as shown in further detail with reference to <FIG>. In the event that the pump <NUM> is replaced or removed, the anchors may retract inwardly from the branch member <NUM> as the branch member <NUM> is withdrawn into the delivery sheath. The branch member <NUM> may have a collar or that interfaces with the pump <NUM>. In other instances, the pump <NUM> and the branch member <NUM> may be correspondingly keyed to fix the pump <NUM> and the branch member <NUM>. The keying may occur by rotation of the pump <NUM> within a deployed branch member <NUM>.

As noted above, the main body <NUM> may be arranged within the aorta <NUM> and more specifically the ascending aorta. The main body <NUM> may protect the aorta <NUM> from the pump <NUM> shifting or shearing. In addition, the main body <NUM> may minimize tissue overgrowth near the pump <NUM> outlet and facilitate retrieval of the pump <NUM>.

<FIG> is an illustration of a delivery sheath <NUM> and a branch member <NUM> of an implantable medical device for cardiac assistance in a first configuration, according to some embodiments. The delivery sheath <NUM> may be used to facilitate delivery (e.g., along with a guidewire and/or delivery catheter) of the branch member <NUM> to connect the aorta and the left atrium (or left ventricle). As shown in <FIG>, the branch member <NUM> is collapsed or constrained within the delivery sheath <NUM>. The branch member <NUM> may include a sealing element <NUM> near or at an end of the branch member <NUM> that is configured to engage a tissue wall of the atrium or the left ventricle.

As shown in <FIG>, the sealing element <NUM> deploys when the branch member <NUM> is deployed from the delivery sheath <NUM>. The sealing element <NUM> may be collapsed against an exterior surface of the branch member <NUM> in the delivery sheath <NUM> and extend outwardly after the branch member <NUM> is deployed. In certain instances, the sealing element <NUM> may be arranged on both ends of the branch member <NUM> with one of the sealing elements <NUM> being configured to dock and seal the branch member <NUM> within a fenestration of a main body (as shown above with reference to <FIG>) and the other of the sealing elements <NUM> being configured to arrange and secure the branch member <NUM> to a tissue wall of the heart.

<FIG> is an illustration of a branch member <NUM> of an implantable medical device arranged within a portal <NUM>, according to some embodiments. The portal <NUM> may be arranged within a main body <NUM> of an implantable medical device for ventricular assist (e.g., as shown in <FIG>). The portal <NUM> may be aligned with an access site <NUM> in the main body <NUM> and the branch member <NUM> may be configured to implant within the portal <NUM> to fluidly connect the branch member <NUM> and the main body <NUM>.

In certain instances, portal <NUM> includes a support wall and secondary lumen having a first longitudinal orientation will therefore define a blood flow direction of the branch member <NUM> that is aligned with the blood flow direction of the main body <NUM>. The support wall of the portal <NUM> may include a stent and a graft component. Further details on internal support walls for supporting branch members extending through access sites in the main body are disclosed in <CIT>.

<FIG> is an illustration of a branch member <NUM> and flange <NUM>, according to some embodiments. The flange <NUM> may be configured to engage a tissue wall <NUM> in a fluid tight fluid engagement between the branch member <NUM> and atrium or ventricle into which the branch member <NUM> is arranged. The flange <NUM> prevents leakage between the puncture made in the atrium or ventricle and the branch member <NUM>.

The flange <NUM> may be integrated with the branch member <NUM> or separately deployed and anchored with the branch member <NUM>. In certain instances, the flange <NUM> may be balloon expandable to deploy about the tissue wall <NUM>. The flange <NUM> may extend and flatten out around the tissue wall <NUM> after balloon or self-expansion after deployment from a delivery sheath <NUM> as discussed in detail above. The flange <NUM> may include a stent and/or a graft portion or may include a polymeric material.

<FIG> is an illustration of another implantable medical device for cardiac assistance, which is not according to the claimed invention as it does not show an access site in a sidewall of the main body. The implantable medical device is shown implanted in a patient's aorta <NUM> leading from a patient's heart <NUM>. The patient's heart <NUM> is a simplified diagram and includes the aortic valve <NUM>, the right atrium (RA), left atrium (LA), right ventricle (RV), and left ventricle (LV).

In certain instances, the implantable medical device includes a main body <NUM> configured to deploy within the aorta <NUM>. The main body <NUM> includes a lumen maintaining fluid flow through the aorta <NUM>. In addition, the main body <NUM> also includes a portal <NUM> coupled to the main body <NUM> providing access to the lumen of the main body <NUM>. The implantable medical device may also include a branch member <NUM> configured to deploy within the portal <NUM> to fluidly connect with the lumen of the main body <NUM>. The branch member <NUM> may include a pump <NUM> configured to convey blood through the branch member <NUM> and into the lumen of the main body <NUM>. The branch member <NUM> and pump <NUM> may include the structural and functional components described above with reference to system <NUM>. In addition and as noted above, the pump <NUM> is configured to increase blood flow into the aorta <NUM> for cardiac assistance. In certain instances, the pump <NUM> may be integrated into the main body <NUM>. In these instances, the main body <NUM> may lack an access site <NUM> and the pump <NUM> may increase blood flow within the aorta <NUM>.

In addition, the branch member <NUM> may be configured to be disposed within the aorta adjacent or across the aortic valve <NUM> or between leaflets of the valve <NUM>. The branch member <NUM> may be configured to allow the aortic valve <NUM> to close about the branch member <NUM> to avoid backflow or leakage while utilized the pump <NUM> may increase blood flow within the aorta <NUM>. In certain instances, the branch member <NUM> includes a cannula <NUM> that extends from end of the branch member <NUM> with the cannula <NUM> being arranged within the aortic valve <NUM>.

<FIG> is an illustration of an example delivery system for an implantable medical device for cardiac assistance, according to some embodiments. The delivery system is shown utilizing both trans-apical access and trans-femoral access sites, which allows delivery of an implantable medical device with a branch member inside of the heart through manipulation of at least two portions or members of the delivery system from outside of the body from the respective trans-apical and trans-femoral access sites. As discussed in further detail below, the delivery system of the present disclosure is transcatheter-based and avoids open heart surgery that may be required for prior cardiac assistance devices.

The delivery system can, for example, be used to deploy an implantable medical device, such as a main body <NUM> for placement in the ascending portion of the aortic. A guidewire <NUM> can be inserted through the trans-apical access site and into the left ventricle <NUM> of the heart <NUM>, as shown in <FIG>. The guidewire <NUM> can be routed through the aortic valve <NUM>, the aorta <NUM>, a femoral artery of one of the legs, and out of the body via the trans-femoral access site (not shown), resulting in a "body floss" or "through-and-through" access configuration, wherein opposite terminal ends <NUM>, <NUM> of the guidewire <NUM> extend outside of the body from respective trans-apical and trans-femoral access sites <NUM>, <NUM>.

A first catheter, generally indicated at <NUM>, includes a leading end <NUM> and an opposite trailing end <NUM>. The first catheter <NUM> has a guidewire lumen <NUM> through which the guidewire <NUM> can be routed. A first end <NUM> of the guidewire <NUM> can be inserted into the guidewire lumen <NUM> at the leading end <NUM> of the first catheter <NUM>. The leading end <NUM> of the first catheter <NUM> can be fed into the vasculature through the trans-apical access site <NUM> via the first introducer sheath <NUM>. The first catheter <NUM> can then be pushed along the guidewire <NUM> in the direction indicated at <NUM> until the leading end <NUM> exits the trans-femoral access site (not illustrated). The trailing end <NUM> of the first catheter <NUM> remains outside of the body and extends from the first access site <NUM> via the first introducer sheath <NUM>. In this configuration, the catheter <NUM> can be maneuvered by pushing or pulling the leading end <NUM> and the trailing end <NUM> of the first catheter <NUM> from outside of the body.

A second catheter, generally indicated at <NUM>, includes a leading end <NUM> and an opposite trailing end <NUM>. The second catheter <NUM> has a guidewire lumen <NUM> for receiving the guidewire <NUM> therethrough. The second end <NUM> of the guidewire <NUM> can be inserted into the guidewire lumen <NUM> at the leading end <NUM> of the second catheter <NUM>. The second catheter <NUM> can be pushed along the guidewire <NUM> until the leading ends <NUM>, <NUM> engage. Although shown with guidewires <NUM>, the catheters <NUM>, <NUM> may be used within guidewires <NUM> in certain instances.

The leading ends <NUM>, <NUM> of the first and second catheters <NUM>, <NUM> can be configured for matingly engaging or coupling to each other. Further, the leading ends <NUM>, <NUM> can be configured for releasably coupling to each other. The leading ends <NUM>, <NUM> of the first and second catheters <NUM>, <NUM> can be coupled to each other extra corporeal or in situ. Once the leading ends <NUM>, <NUM> are coupled, the trailing ends <NUM>, <NUM> of the first and second catheters <NUM>, <NUM> can be accessed outside of the body from the respective trans-apical access site <NUM> and trans-femoral access site <NUM> and pushed, pulled and rotated to axially and rotatably position a main body portion <NUM> of the implantable medical device at the treatment site.

The main body portion <NUM> can be releasably maintained or radially compressed toward a delivery configuration for endoluminal delivery by any suitable constraining means, such as a film constraining sleeve, a constraining tether or lattice, retractable sheath and the like as shown in <FIG>. Optionally, one or more constraining means or combination of constraining means can be configured to allow staged expansion through one or more intermediate expanded states leading to full deployment. The branch member <NUM> (not shown) may be similarly constrained.

Other surgical tools may be delivered through a third access point to the aorta through one of the major branch arteries along the aorta in connection with the deployment of the device at or in the heart or along the aorta. For example, a filter may be deployed to filter blood entering the branch arteries <NUM>, <NUM>, <NUM>.

The catheters <NUM>,<NUM> may also deliver the main body <NUM> and the branch member <NUM> from femoral vein with trans-septal puncture or from apex of heart (trans apical puncture and through mitral up through aorta) or on the ventricle side as well. In certain instances, the main body <NUM> is delivery through the femoral artery and the branch is delivery from the femoral artery or vein.

In delivery the branch member <NUM> across the aorta <NUM> and into the atrium or ventricle, one or both of the catheters <NUM>,<NUM> may include a puncturing device that creates access sites in the tissue wall of the aorta <NUM> and the atrium or ventricle. In addition, one or both of the catheters <NUM>,<NUM> may include a delivery sheath (as noted above) that is pressed against the tissue when and after the access sites are created. Magnets or other coupling members in the delivery sheaths of the catheters <NUM>,<NUM> may attach together for deployment of the branch member <NUM>.

The catheters <NUM>,<NUM> may be used to deploy the main body <NUM> in the aorta <NUM> and the branch member <NUM> across the aorta <NUM> and into the atrium or ventricle. More specifically, the first catheter <NUM> may deploy the main body <NUM> and the second catheter <NUM> may deploy the branch member <NUM>. In other instances, the main body <NUM> can be deployed in the aorta <NUM> and the branch member <NUM> can be deployed across the aorta <NUM> and into the atrium or ventricle by using one of the catheters <NUM>, <NUM> with a trans-septal approach (across atrial septum into the left atrium) and the other of the catheters <NUM>, <NUM> using a femoral approach.

<FIG> is an illustration of a branch member according to some embodiments. <FIG> is an illustration of a pump, according to some embodiments. <FIG> is a cross sectional view of the branch member shown in <FIG>, taken along line 8A-8A. <FIG> is a cross sectional view of the pump shown in <FIG>, taken along line 8B-8B.

With reference now to <FIG>, the branch member <NUM> generally includes a stent body <NUM> defining an exterior <NUM> and an interior <NUM>. The stent body <NUM> may be generally cylindrically shaped and configured to adopt a profile consistent with the vasculature within which is it deployed and expanded. In some examples, the stent body <NUM> is defined by a plurality of interconnected strut elements <NUM> or helically wound strut elements <NUM>.

For example, as shown in <FIG>, the pump <NUM>, arranged within at least a portion of the branch member <NUM> or extending from the branch member <NUM>, generally includes a pump housing <NUM> and a pump drive element <NUM>. The pump housing <NUM> generally defines an exterior <NUM> and an interior <NUM>. The exterior <NUM> of the pump housing <NUM> is configured to engage and interface with the interior <NUM> of the branch member <NUM> such that the pump <NUM> can be coupled with the branch member <NUM>. The interior <NUM> of the pump housing <NUM> is configured to house or accommodate the pump drive element <NUM> such that the pump drive element <NUM> can move relative to the pump housing <NUM> to cause blood to flow through the pump <NUM>. In some examples, blood travels through the pump <NUM> within an annular space <NUM> that is defined between the pump drive element <NUM> and the pump housing <NUM>, although other pump configurations are contemplated and fall within the scope of the present disclosure provided that the pump housing can be configured to interface and engage with the branch member <NUM>. Thus, although the pump drive element <NUM> shown in <FIG> includes a worm drive having a helical flange extending about a central shaft (e.g., an impeller configuration), the application should not be understood to be limited to such configuration, but should instead be understood to be operable with other pump drive configurations.

As mentioned above, in various embodiments, the pump <NUM> is receivable within the branch member <NUM>. As shown in <FIG>, the each of the pump <NUM> and the branch member <NUM> include complementary features that facilitate the coupling of the branch member <NUM> with the pump <NUM>.

As shown in <FIG>, the branch member <NUM> includes a plurality of pump locating features 108a, 108b, and 108c. In this illustrated example, the pump locating features 108a-108c are channels or recesses that extend longitudinally along a longitudinal axis of the branch member <NUM>. In some examples, the pump locating features 108a-108c extend parallel to the longitudinal axis of the branch member <NUM>. In some examples, one or more of the pump locating features 108a-108c extend along less than all of the length of the branch member <NUM>. That is, in some examples, the pump locating features 108a-108c extend only partially between the first end <NUM> and the second end <NUM> of the branch member <NUM>. In some such examples, one or more of the pump locating features 108a-108c terminates at a location between the first and second ends <NUM> and <NUM>. This termination of the one or more channels or recesses of the pump locating features 108a-108c operates as an abutment against which the pump housing <NUM> of the pump <NUM> can sit.

As explained further below, such a configuration provides that the pump housing <NUM> of the pump <NUM> may only be inserted into and removed from the branch member <NUM> in a unidirectional manner. For instance, when inserted into the branch member <NUM>, the pump <NUM> can be advance longitudinally along the branch member <NUM> until the pump housing <NUM> engages the termination point of the one or more channels or recesses of the pump locating features 108a-108c. Moreover, when being removed from the branch member <NUM>, the pump <NUM> can only be withdrawn in a direction opposite from that direction in which the pump <NUM> was advanced when it was coupled to the branch member <NUM>. Securing the pump <NUM> within the branch member <NUM> in such a manner operates to prevent the pump <NUM> from being drawn through the branch member <NUM>.

As mentioned above, the pump housing <NUM> generally includes one or more features that are complimentary of the pump locating features 108a-108c of the branch member <NUM>. With reference now to <FIG>, the pump housing <NUM> is shown as including a plurality of stent engagement elements 216a, 216b, and 216c. As shown, the stent engagement elements 216a-216c are features that protrude from the exterior of the pump housing <NUM>. The stent engagement elements 216a-216c extend longitudinally along the exterior <NUM> of the pump housing <NUM>, such as parallel to a longitudinal axis of the pump housing <NUM>. In some examples, the stent engagement elements 216a-216c extend between the first end <NUM> and the second end <NUM> of the pump housing <NUM>. In some examples, one or more of the stent engagement elements 216a-216c may extend beyond (or alternatively short of) one or more of the first and second ends <NUM> and <NUM> of the pump housing <NUM>. The stent engagement elements 216a-216c are generally complimentary in shape, size, and location and orientation of the pump locating features 108a-108c such that the stent engagement elements 216a-216c can be received within the pump locating features 108a-108c.

As shown in <FIG>, the stent engagement elements 216a-216c are formed as positive dovetail features while the pump locating features 108a-108c are formed as the complimentary negative dovetail features. Additionally, the stent engagement elements 216a-216c are shown as being evenly distributed circumferentially about the exterior <NUM> of the pump housing <NUM>, while the pump locating features 108a-108c are similarly evenly distributed circumferentially about the interior <NUM> of the branch member <NUM>.

It is to be appreciated that the interaction between the stent engagement elements 216a-216c and the pump locating features 108a-108c operates to help locate the pump <NUM> within the branch member <NUM>. For instance, the engagement between stent engagement elements 216a-216c and the pump locating features 108a-108c (the combination of which are referred to herein as alignment features) helps to align the pump <NUM> longitudinally with respect to the branch member <NUM>. Likewise, the engagement between stent engagement elements 216a-216c and the pump locating features 108a-108c helps to align the pump <NUM> coaxially with the branch member <NUM>.

Additionally, in various examples, this interaction also operates to prevent pitch/yaw/roll (e.g., rotation relative to the longitudinal axis of the branch member <NUM>) of the pump housing <NUM> relative to the branch member <NUM> during operation of the system <NUM>, which provides the constraint necessary to allow the pump <NUM> to operate to drive blood flow across the pump <NUM> (e.g., the pump drive element <NUM> can rotate or be rotated relative to the pump housing <NUM> without the pump housing <NUM> also rotating).

In various examples, with the pump <NUM> properly aligned and seated within the branch member <NUM>, the pump housing <NUM> and the branch member <NUM> form a seal therebetween such that blood cannot flow between the pump housing <NUM> and the branch member <NUM>. In some examples, the pump housing <NUM> is suspended within the branch member <NUM> such that blood can flow either through/across the pump drive element <NUM>, or around the pump housing <NUM>. Such a configuration allows for blood flow around the pump in the case of a pump failure, and additionally provides favorable hemodynamics with regard to hemolysis and perfusion of the coronary arteries. In some examples, bypass blood flow (e.g., blood flow around the pump <NUM> may be facilitated by the branch member <NUM>, itself. For instance, in some examples, the branch member <NUM> may include an open celled stent structure, wherein the pump <NUM> is positioned within or suspended by the open celled stent branch member, which allows for blood to flow through and around the pump <NUM> (e.g., through the open cells of the stent branch member.

It is also to be appreciated that while the branch member <NUM> and the pump <NUM> shown in <FIG> include complementary alignment features that are in the shape of dovetails, various other sizes and shapes of such features are envisioned and can be implemented without departing from the spirit or scope of the present disclosure. For example, the dovetail geometry may be replaced with one or more of various alternative geometries, including but not limited to, triangles, squares, and polygons. Similarly, though the <FIG> show three evenly distributed (e.g., positioned <NUM> degrees away from each other) alignment features (e.g., stent engagement elements 216a-216c and pump locating features 108a-108c), as little as one or two such alignment features may be used, or more than three such alignment features may be used. Likewise, where more than one alignment feature is used, such alignment features need not be evenly distributed about the interior/exterior of the branch member <NUM> and the pump housing <NUM>.

It should also be appreciated that while the alignment features shown in <FIG> extend longitudinally along the branch member <NUM> and the pump housing <NUM>, the alignment features may alternatively be arranged in a helical pattern. In such an alternative configuration, the pump <NUM> is coupleable with the branch member <NUM> by aligning the helical alignment features of the pump <NUM> and the branch member <NUM> with one another and then rotating the pump <NUM> and the branch member <NUM> relative to one another, such as about the longitudinal axis of the branch member <NUM>, for example.

It should also be appreciated that while the branch member <NUM> and the pump <NUM> shown in <FIG> are shown with the alignment features protruding from the exterior <NUM> of the pump housing <NUM> and as channels or recesses along the interior <NUM> of the branch member <NUM>, in some other examples, the alignment features may protrude from the interior <NUM> of the branch member <NUM> and be formed as recesses or channels along the exterior <NUM> of the pump housing <NUM>. Alternatively, the branch member <NUM> and the pump housing <NUM> may each include a combination of alignment features that protrude therefrom and that are formed as recesses or channels therein.

<FIG> shown a variety of additional configurations for the various components (e.g., the branch member <NUM>, the pump <NUM>, the retention element <NUM>, and the driveline <NUM>) of the systems disclosed herein. For instance, in some examples, the branch member <NUM> may include one or more support components (e.g., components "a" and "b") that project radially inwardly and are configured to interface with and support the pump <NUM> within the branch member <NUM>, as shown. In some examples, the pump <NUM> may include one or more features that are complementary of the support components "a" and "b" of the branch member <NUM>, and that engage therewith to couple the pump <NUM> to the branch member <NUM>, such that the pump <NUM> is suspended within an interior of the branch member <NUM> (e.g., within a lumen defined by an interior of the branch member <NUM>). As shown, the pump <NUM> is coaxially aligned with the branch member <NUM>, wherein an exterior of the pump <NUM> is offset from an interior of the branch member <NUM> such that an annular void is defined between the interior of the branch member <NUM> and the pump <NUM>. In various examples, blood is operable to flow through such an annular void (e.g., in conjunction with, or as an alternative to blood flow through the pump <NUM>).

<FIG> is an illustration of an example branch member <NUM> with flanges 520a, 520b, according to some embodiments. The branch member <NUM> creates a fluidic connection between spaces or tissue structures such as the aorta and an atrium or ventricle as discussed in detail above. As shown, the branch member <NUM> includes flanges 520a, 520b. The flanges 520a, 520b may be arranged to seal the branch member <NUM> within tissue structures or within a main body <NUM> of an implantable medical device as discussed above. In instances where the branch member <NUM> includes two flanges 520a, 520b as shown, the main body <NUM> includes a fenestration (either created after implantable or prior to implantation).

The branch member <NUM> includes a lumen <NUM> that extends longitudinally from a first end of the branch member <NUM> to a second end of the device <NUM>. The lumen <NUM> acts as a connection (e.g., a shunt passageway) between the main body <NUM>, implanted in the aorta, and the internal intestinal space of the heart (e.g., atrium or ventricle), such that the main body <NUM> is in fluid communication with the atrium or ventricle via the anastomosis device branch member <NUM>. The flange 520b may be configured to contact a tissue wall <NUM> as described in detail above. A wall <NUM> of the lumen <NUM> may be sized to interference fit with a pump <NUM>.

<FIG> is an illustration of another implantable medical device for cardiac assistance, which is not according to the claimed invention as it does not show an access site in a sidewall of the main body. The implantable medical device is shown implanted in a patient's aorta <NUM>, and more particularly within the descending aorta <NUM>, leading from a patient's heart <NUM>. The patient's heart <NUM> is represented as a simplified diagram and includes the aortic valve <NUM>, the right atrium (RA), left atrium (LA), right ventricle (RV), and left ventricle (LV).

In certain instances, the implantable medical device includes a main body <NUM> configured to deploy within the aorta <NUM>. The main body <NUM> includes a lumen maintaining fluid flow through the aorta <NUM>. In addition, the main body <NUM> also includes a portal coupled to the main body <NUM> providing access to the lumen of the main body <NUM>. The implantable medical device may also include a branch member <NUM> configured to deploy within the fenestration or portal (as described, respectively, above with reference to <FIG> and <FIG>) to fluidly connect with the lumen of the main body <NUM>. Though shown coupled to the branch member <NUM>, in certain instances, the pump <NUM> may be integrated into, or otherwise coupled with the main body <NUM>.

As referenced above, the branch member <NUM> may include a pump <NUM> configured to convey blood through the branch member <NUM> and into the lumen of the main body <NUM>. The branch member <NUM> and pump <NUM> may include the structural and functional components described above with reference to system <NUM>. In addition and as noted above, the pump <NUM> is configured to increase blood flow into the aorta <NUM> for cardiac assistance.

As shown in <FIG>, the pump <NUM> and/or branch member <NUM> may be arranged within a left atrial appendage (LAA) of the heart <NUM>. The branch member <NUM> may exit the LAA to couple to the main body <NUM> arranged within the descending aorta <NUM>. The main body <NUM> may be arranged within other portions of the aorta <NUM>. In certain instances, the pump <NUM> and branch member <NUM> include a sealing element <NUM> or flange (e.g., as shown in <FIG>) to secure and position the pump <NUM> and branch member <NUM> within the LAA. In other instances, a stent structure <NUM> may be coupled to the branch member <NUM> and/or pump <NUM>.

In certain instances and as shown, the stent structure <NUM> may contact interior walls of the LAA. The stent structure <NUM>, as shown in further detail in <FIG>, may stabilize the pump <NUM> and/or branch member <NUM> within the LAA. The stent structure <NUM> may be configured to conform to the shape of the LAA (e.g., including an acorn or tapered shape). In addition, the stent structure <NUM> may be at least partially covered by a membrane to seal off the LAA about the pump <NUM> and/or branch member <NUM>. The stent structure <NUM> may include a central eyelet through which the pump <NUM> and/or branch member <NUM> are arranged. Further, the stent structure <NUM>, which may include the membrane, lessens turbulent blood flow across the LAA to minimize the opportunity for thrombus formation. For further discussion and detail regarding some suitable designs for the stent structure <NUM>, reference may be made to <CIT>, <CIT>, and <CIT>, which discuss left atrial appendage medical devices.

In certain instances, the pump <NUM> may be coupled to a driveline <NUM> that is coupled to a controller configured to control the operation of the pump <NUM>. As shown in <FIG>, the driveline <NUM> may be routed through the heart <NUM> septum to the right atrium and through the vena cava.

In certain instances, the branch member <NUM> may include a portion that is arranged directly within the aorta <NUM> without the main body <NUM>. In certain instances, the branch member <NUM> includes a first end portion configured to deploy within the left atrial appendage of a heart and a second end portion configured to deploy within the aorta <NUM>. The branch member <NUM>, as discussed in detail above, is configured to interface with the pump <NUM> to pass blood flow through a lumen of the branch member <NUM> from the left atrial appendage into the aorta <NUM>. The branch member <NUM> may include a flange configured to engage a tissue wall of the aorta (e.g., as shown in <FIG> and <FIG>). The flange may be configured to engage the tissue wall in a fluid tight fluid communication between the branch member <NUM> and the tissue wall of the aorta <NUM>.

In certain instances, the branch member <NUM> (or pump <NUM>) may be anastomosed to the aorta <NUM> (e.g., using flanges). The pump <NUM> may be configured to intake blood from the left atrial appendage and discharge the blood into the aorta <NUM>. When the branch member <NUM> is directly coupled to the aorta <NUM>, the outflow of the pump <NUM> is directly to the aorta <NUM> through the branch member <NUM>.

<FIG> is an illustration of another implantable medical device for cardiac assistance arranged within a left atrial appendage and including a stent structure <NUM>, according to some embodiments. As shown, the pump <NUM> and branch member <NUM> is arranged through the stent structure <NUM>. The stent structure <NUM> may include an occlusive face that is arranged near an ostium <NUM> of the left atrial appendage. In addition and as shown, the stent structure <NUM> includes frame components <NUM> and a membrane <NUM> covering the frame components.

<FIG> is an illustration of an example implantable medical device for cardiac assistance, which is not according to the claimed invention as it does not show an access site in a sidewall of the main body. The system <NUM> may be used as an implantable medical device for cardiac assistance as shown in <FIG>. As shown in <FIG>, a main body <NUM> portion of an implantable medical device is arranged within a patient's aorta <NUM> leading from a patient's heart <NUM>. The patient's heart <NUM>.

The main body <NUM> includes a lumen maintaining fluid flow through the aorta <NUM>. In addition, the main body <NUM> also includes an access site <NUM> on a sidewall of the main body <NUM> providing access to the lumen of the main body <NUM>. The access site <NUM> may be a fenestration created before or after implantation of the main body <NUM>. In addition, the main body <NUM> may include radiopaque markers arranged near adjacent the access site <NUM> to facilitate deployment. Further, the access site <NUM> may be deployed as facing away from the brachiocephalic, subclavian, and carotid arteries. The main body <NUM> may include a curvature or conform to a curvature of the aorta with the access site <NUM> being arranged opposite the curvature and thus be arranged as facing away from the brachiocephalic, subclavian, and carotid arteries.

The implantable medical device may also include a branch member <NUM> configured to deploy within the access site <NUM> to fluidly connect with the lumen of the main body <NUM>. As noted above, to facilitate coupling of the branch member <NUM> and the main body <NUM>, the access site <NUM> of the main body <NUM> fluidly connects with the lumen of the main body <NUM>. The access site <NUM> in the main body <NUM> may include a fenestration or a portal.

As shown in <FIG>, the branch member <NUM> is arranged external to the heart <NUM>. In certain instances, the branch member <NUM> is arranged about a patient's heart <NUM>. The implantable medical device may also include a pump <NUM> arranged within a chamber of the heart <NUM> that is configured to convey blood through the branch member <NUM> and into the lumen of the main body <NUM>. In certain instances, the pump <NUM> is configured to be disposed within a left ventricle of the patient's heart <NUM> and convey blood through the branch member <NUM> and into the lumen of the main body <NUM>.

Implanting the branch member <NUM> to connect the pump <NUM> to the main body <NUM> in the aorta may function as a cardiac assist device with the pump <NUM> forcing blood from one or more chambers of the heart into the aorta <NUM>. The branch member <NUM>, main body <NUM>, and pump <NUM> may be used to assist heart function for patients' having weakened hearts or heart failure. In addition and as noted above, the pump <NUM> may be configured to increase blood flow into the aorta <NUM> for cardiac assistance.

To deliver the branch member <NUM> and connect the aorta <NUM> and the pump <NUM>, a puncturing device (e.g., arranged through the access site <NUM>) creates a small access site in a tissue wall of the aorta <NUM>. The branch member <NUM> may be arranged within the access site <NUM> after puncturing the aorta <NUM> (which may then be sealed (e.g., the main body <NUM> seals within and external to the aorta <NUM> by having an overlap between the branch member <NUM> and the access site <NUM>). The branch member <NUM>, for example, may include stent-and graft components (as noted above with reference to <FIG>) that allow for flexibility and relative motion between the aorta <NUM> and the pump <NUM>.

In addition, the branch member <NUM> and pump <NUM> combination provides direct increase of blood flow for cardiac assistance. The branch member <NUM> and pump <NUM> may be configured to deliver the blood flow through the branch member <NUM> and into the lumen of the main body <NUM> parallel to native blood flow through the aorta <NUM>. The branch member <NUM>, the main body <NUM>, and the pump <NUM> may be collapsed to a delivery configuration of transcatheter delivery. Having the main body <NUM> arranged in the aorta <NUM> mitigates the risk of aortic dissection, protects the aortic wall from an increased fluid flow from the pump <NUM>, and may reduce risk of device deployment.

Arranging the main body <NUM> and the branch member <NUM> and pump <NUM> in this manner facilitates connection of a pump <NUM> to the aorta <NUM> without an additional open heart procedure. The main body <NUM> and the branch member <NUM> and pump <NUM> may be sutureless, percutaneous, and anastomotic. The main body <NUM> and the branch member <NUM> and pump <NUM> may also provide in-line (or parallel) flow that can reduce shear and turbulence which could damage the blood or consume blood proteins, and potentially reduces back-pressure on the heart. The main body <NUM> and the branch member <NUM> and pump <NUM> may also protects the aorta locally from shear-induced damage (e.g., dissection, intimal hyperplasia) and/or decouples the motion of the heart from the motion of the aorta <NUM>, allowing native motion while minimizing the risk of erosion or pull-out. In certain instances, the branch member <NUM> may be arranged directly within the aorta <NUM> without the main body <NUM>.

<FIG> is an illustration of an example implantable medical device for cardiac assistance for implantation into a pulmonary vein, according to some embodiments. The implantable medical device may be a pump <NUM>, or in other instances, the implantable medical device may be a pump <NUM> that deploys within a main body that may include a stent, graft, or stent-graft combination for implantation into a vessel of a patient. In certain instances, the implantable medical device is configured to deploy within a pulmonary vein <NUM> and the implantable medical device includes a lumen maintaining fluid flow through the pulmonary vein <NUM>. In certain instances, the pump <NUM> may be arranged within the vena cava (inferior or superior) to facilitate right ventricular assistance. The pump <NUM> may be arranged within a branch member <NUM> in certain instances and arranged within the vena cava. In other instances, the pump <NUM> (with or without the branch member <NUM>) may be arranged within the descending or thoracic aorta, or peripheral vessels to facilitate blood flow. In addition, the pump <NUM> (with or without the branch member <NUM>) may increase flow of other non-blood bodily fluids when placed in other areas of the body (e.g., urinary, biliary).

The implantable medical device may also include a pump <NUM> arranged within the main body of the implantable medical device that is configured to convey blood through the lumen of the main body. In certain instances, the pump <NUM> is configured to intake blood flow into the left atrium <NUM>. In addition, the pump <NUM> may be configured to increase flow out of the pulmonary vein <NUM> to increase cardiac output.

In certain instances, the pump <NUM> includes a driveline <NUM> configured to power the pump <NUM>. The driveline <NUM> may be coupled to the pump <NUM> and arranged out of the pulmonary vein <NUM> into the left atrium <NUM> and across a septum to exit a right side of the heart. In certain instances, the driveline <NUM> exits a patient via an iliac vein. The pump <NUM> may facilitate direct filing of the ventricles when the pump <NUM> is implanted in the pulmonary vein <NUM>. The pump <NUM> being implanted into the pulmonary vein <NUM> may facilitate increased pulmonary circulation, decrease risk of chronic obstructive pulmonary disease (COPD), increase cardiac output, and implant a cardiac assistance device using venous access, which can reduce access site complications as compared to arterial access.

In certain instances, the pump <NUM> may be used to facilitate flow within another vessel. The pump <NUM> may be implanted for vessel-vessel communication (e.g., percutaneous fistula creation). In addition, the pump <NUM> may include or be coupled to a drug delivery reservoir with the pump <NUM> pumping blood and a therapeutic drug within a patient. In other instances, the pump <NUM> may include a sensor used to sample blood within a patient. In addition, the sensor may be incorporated with the pump to measure blood flow and indicate the flow to a physician for monitoring.

<FIG> is an illustration of an example implantable medical device for cardiac assistance, according to some embodiments. As shown in <FIG>, a pump <NUM> is arranged between a patient's aorta <NUM> and a patient's heart <NUM>. The pump <NUM>, in certain instances, is arranged in the left atrium, right atrium or left ventricle. The pump <NUM> is configured to force blood flow from the heart chamber into the aorta <NUM>.

To seal the pump <NUM> in the heart <NUM> and the aorta <NUM>, a conduit of native tissue <NUM> about the pump and between the aorta and the heart chamber. In certain instances, the conduit of native tissue <NUM> may be formed by creating or tissue ingrowth to form a tissue layer between the aorta <NUM> and the heart <NUM>. The pump <NUM> may include a material arranged about an outer surface of the pump <NUM> that configured to facilitate tissue ingrowth. In certain instances, the material includes at least one of Dacron and ePTFE.

The material may be a graft or covering component that can have a microporous structure that provides a tissue ingrowth scaffold. In certain instances, the covering component may include a fluoropolymer, such as an expanded polytetrafluoroethylene (ePTFE) polymer. In some examples, the covering component can be a membranous covering. In some examples the covering component can be a film. The covering component may be modified with covalently attached heparin or impregnated with one or more drug substances that are released in situ to promote wound healing. In some instances, the drug may be a corticosteroid, a human growth factor, an anti-mitotic agent, an antithrombotic agent, or dexamethasone sodium phosphate.

After the conduit of native tissue <NUM> is formed, the pump <NUM> may be removed. In certain instances, the conduit of native tissue <NUM> may be relined with another material (e.g., a membrane or graft material) after the conduit of native tissue <NUM> is formed.

<FIG> is a top view of an example implantable medical device for cardiac assistance for implantation as a heart valve, according to some embodiments. <FIG> is an illustration of the example implantable medical device shown in <FIG> arranged as a heart valve, according to some embodiments. The implantable medical device is a heart valve device that includes a support frame <NUM>. A plurality of leaflets 562a-c are coupled to the support frame <NUM>. The plurality of leaflets 562a-c are configured to open to allow forward flow therethrough and to occlude the support frame <NUM> to prevent retrograde flow. A pump <NUM> may also be arranged with the support frame <NUM>. The pump <NUM> may be configured to force blood through the support frame <NUM>.

In certain instances and as shown in <FIG>, the plurality of leaflets 562a-c are configured to coapt about the pump <NUM> arranged within the support frame <NUM>. The pump <NUM> may be arranged centrally within the support frame <NUM>, with the leaflets 562a-c closing onto the pump <NUM>. The prosthetic valve (the support frame <NUM> and the leaflets 562a-c) and the pump <NUM> may configured to transcatheter delivery. In certain instances, the prosthetic valve is configured to replace an aortic valve of a patient and in other instances, the prosthetic valve is configured to replace a mitral valve of a patient.

In certain instances, a filter <NUM> may be arranged on an outflow end of the support frame <NUM>. More specifically, the filter <NUM> may be arranged at the outflow end of the pump <NUM>. The filter <NUM> may facilitate protection against emboli passing through the support frame <NUM>.

A method of delivering the support frame <NUM> and pump <NUM> via a catheter can comprise providing a delivery catheter having an expandable support frame <NUM> in a collapsed state constrained over or within the delivery catheter at a distal end of the delivery catheter; passing the delivery catheter through the introducer sheath and into valve annulus; positioning the distal end of the delivery catheter so that the support frame <NUM> is properly positioned and oriented within the valve annulus; and expanding the support frame <NUM> at the valve annulus into contact therewith.

<FIG> is an illustration of an example implantable medical device <NUM> for cardiac assistance, which is not according to the claimed invention as it does not show an access site in a sidewall of the main body. System <NUM> may form a portion of the implantable medical device <NUM> for cardiac assistance shown in <FIG>. For example, the implantable medical device <NUM> includes a main body <NUM> portion that is configured to be deployed within a patient's aorta leading from a patient's heart. The implantable medical device <NUM> may also include a branch member <NUM> extending from the main body <NUM> and configured to deploy within a chamber of the heart to fluidly connect the aorta and the chamber of the heart. In certain instances, the branch member <NUM> may be integral with the main body <NUM>. The branch member <NUM> may extend from an end portion of the main body <NUM> (as shown in <FIG>) or the branch member <NUM> may extend from circumferentially from the main body <NUM>.

The branch member <NUM> being integral with or forming a portion of the main body <NUM> may facilitate deployment of the main body <NUM> and the branch member <NUM> from same deployment location, direction, or using the same catheter device. In certain instances, the main body <NUM> may be arranged within the aorta via the femoral artery and into the aorta. After deploying the main body <NUM>, punctures may be made in the aorta and a chamber of the heart (atrium or ventricle) via the same femoral access. In certain instances, a guidewire used to deploy the main body <NUM> may be used to puncture tissue in the aorta and the chamber of the heart. Immediately after puncturing the aorta and the chamber of the heart, the branch member <NUM> may cross the aorta and the chamber of the heart. In certain instances, puncture and delivery of the branch member <NUM> may occur in the same action (e.g.,_using the same guidewire). Thus, leakage may be minimized by deploying the branch member <NUM> in an immediately sequence. In addition, the deployment and puncturing may occur using a singular delivery handle/system.

The implantable medical device <NUM> may also include a pump <NUM> (not shown). As discussed in detail above, the pump <NUM> may be arranged within the branch member <NUM> and configured to force blood flow from the chamber of the heart through the branch member <NUM> and into the lumen of the main body <NUM>. To deploy the pump <NUM>, the pump <NUM> may be arranged through the inferior vena cava (IVC), across the septum of the heart and deployed with the branch member <NUM>.

The main body <NUM> and the branch member <NUM> may include stent, graft, or stent and graft components. In addition, the branch member <NUM> may be configured to telescope inwardly and outwardly relative to the main body <NUM>. In certain instances, the branch member <NUM> may collapse and extend to alter a length of the branch member <NUM>.

<FIG> is an illustration of an example branch member <NUM>, according to some embodiments. As noted above, the branch member <NUM> may be configured to interface with a pump (not shown) to pass blood flow through the branch member <NUM> into the main body. In other instances, the branch member <NUM> may a support frame used in a prosthetic valve (e.g., as shown in <FIG>). The branch member <NUM> (or support frame) may be delivered to a target location and removably couple to a pump after the branch member <NUM> has been delivered and deployed within the patient (e.g., a branch member of an implantable medical device).

In certain instances, the branch member <NUM> (or support frame) may be configured to anchor the pump within the branch member. As shown in <FIG>, for example, the branch member <NUM> (or support frame) may include an attachment mechanism <NUM> that is configured to anchor the pump with the branch member <NUM> (or support frame). In certain instances, each of the branch member <NUM> (or support frame) and the pump may include complementary attachment mechanisms <NUM>, <NUM> to anchor the pump within the branch member <NUM>. In addition and alternatively to the attachment mechanism <NUM> or complementary attachment mechanisms <NUM>, <NUM>, the branch member <NUM> (or support frame) may be configured to frictionally engage with the pump to anchor the pump within the branch member <NUM>.

<FIG> is an illustration of a pump <NUM> and a hinge structure <NUM> in a first configuration, according to some embodiments. The hinge structure <NUM> may be the anchor element for the pump <NUM>. In certain instances, the hinge structure <NUM> is configured to articulate a portion of the pump <NUM> and maintain the pump <NUM> in an angled configuration as shown in <FIG>. The hinge structure <NUM> may maintain the pump <NUM> at an angle after a force is applied to alter the configuration of the pump <NUM>.

In certain instances, the pump <NUM> includes a tubular portion <NUM> and the hinge structure <NUM> is arranged circumferentially within or about the tubular portion <NUM>. In addition, the pump <NUM> may have multiple hinge structures <NUM> arranged at different positions along a length of the tubular portion <NUM>. Multiple hinge structures <NUM> may facilitate bending of the tubular portion <NUM> at different angles and/or initiate bending at different portions along a length of the tubular portion <NUM>. Bending at the hinge structure <NUM> creates fixation between the pump <NUM> and the branch member <NUM>.

The hinge structure <NUM> may include a plurality of discrete rings configured to maintain the tubular portion <NUM> in the angled configuration in response to an applied force. In certain instances, the discrete rings of the hinge structure <NUM> may be metal stent-like structures. In addition, the hinge structure <NUM> may also be formed by a corrugated portion of the tubular portion <NUM>. The tubular portion <NUM>, along with a motor and impeller as described above with reference to <FIG>, may include a stent, a stent-graft, or a graft. In certain instances, the corrugated portion of the tubular portion <NUM> may be formed of a graft material. In addition and as noted above with reference to <FIG>, the pump <NUM> may include a driveline configured to couple to a controller that drives the pump <NUM>.

The pump <NUM> may be delivered into branch member <NUM> by a catheter. The catheter may be deflected to angle the hinge structure <NUM>. In instances where the pump <NUM> is to be removed, a catheter may be routed to the branch member <NUM>, and the hinge structure <NUM> may be un-articulated. The hinge structure <NUM> may engage with a branch member <NUM> arranged in a portal or a fenestration of a main body graft. In addition, the hinge structure <NUM> may be include a shape memory material (e.g., Nitinol) such that the hinge structure <NUM> is arranged in a substantially linear configuration (e.g., as shown in <FIG>) during delivery but shape set into an elbow or angled configuration (as shown in <FIG>). In these instances, the hinge structure <NUM> will deploy to the angled configuration after delivery and engage the branch member <NUM>.

<FIG> is an illustration of an example pump <NUM> and anchor element <NUM>, according to some embodiments. As shown in <FIG>, the anchor element <NUM> is arranged on an external surface of the pump <NUM>. The anchor element <NUM> may be configured to expand and engage an interior surface of a branch member.

In certain instances, the anchor element <NUM> is an expandable balloon <NUM> configured to expand and engage an interior surface of the branch member. The expandable balloon <NUM> may be coupled to an inflation/deflation pump <NUM> by way of a conduit <NUM>. The inflation/deflation pump <NUM> may be arranged internal or external to the patient and the conduit <NUM> may be routed similar to the driveline. In certain instances, the expandable balloon <NUM> may be arranged circumferentially about the pump <NUM>.

In certain instances, the anchor element <NUM> is or includes spring <NUM> arranged on the external surface of the pump <NUM>. The anchor element <NUM> may also include the expandable balloon <NUM>, which is configured to collapse the spring <NUM> in response to inflation. In certain instances, the expandable balloon <NUM> may be deflated to collapse the spring and close a gap between the pump <NUM> and the branch member.

In either instance, the expandable balloon <NUM> may be inflated and deflated to reposition the pump <NUM>. In addition, the expandable balloon <NUM> creates an interference fit between the pump <NUM> and the branch member. The expandable balloon <NUM> may be filled with liquid (e.g., saline, contrast medium) or air. in addition, the expandable balloon <NUM> may be backfilled with curing fluid that solidifies if the pump <NUM> is permanently implanted within the branch member <NUM>. the curing fluid may also be dissolvable such that the pump <NUM> is not permanently implanted within the branch member <NUM>.

<FIG> is an illustration of another example pump <NUM> and anchor element <NUM>, according to some embodiments. As shown in <FIG>, the anchor element <NUM> is arranged at an end portion <NUM> of the pump <NUM>. In addition, the anchor element <NUM> includes a plurality of flanges <NUM> extending radially from the end portion <NUM> of the pump <NUM>.

The flanges <NUM> may include a self-expanding material (e.g., Nitinol) that extend radially from the end portion <NUM> of the pump <NUM>. The pump <NUM> may be arranged within a delivery sheath and the flanges <NUM> may extend after the pump <NUM> is arranged out of the delivery sheath. In certain instances, the pump <NUM> may be arranged directly between the aorta and an atrium or ventricle with the flanges <NUM> deploying within the aorta without a main graft. In these instances, the flanges <NUM> may be configured to facilitate tissue ingrowth.

<FIG> is an illustration of an example branch member <NUM>, pump <NUM>, anchor element <NUM>, and receiving structure <NUM>, according to some embodiments. As shown in <FIG>, the pump <NUM> is arranged within and engaged with the branch member <NUM>. The pump <NUM> includes the anchor element <NUM> along an external surface of the pump <NUM> and the branch member <NUM> includes the receiving structure <NUM> along an internal surface of the branch member <NUM>. The anchor element <NUM> is configured to engage the receiving structure <NUM> to removably fix the pump within the branch member. In certain instances, the anchor element <NUM> is a stent <NUM> and the receiving structure <NUM> is configured to contain the stent <NUM> to removably fix the pump <NUM> within the branch member <NUM>.

In certain instances, the stent <NUM> is self-expanding after the pump <NUM> is arranged out of a delivery sheath. In addition, the stent <NUM> may be elastic such that movement of the pump <NUM> into the branch member <NUM> overcomes friction of the and receiving structure <NUM> and nests within the receiving structure <NUM>. The receiving structure <NUM> may include end portions <NUM>, <NUM> that produced outwardly and create nesting area of the stent <NUM>.

As shown, there are more than one of each of the stent <NUM> and the receiving structure <NUM>. In certain instances, the stent <NUM> and the receiving structure <NUM> may be discrete elements about the outer circumference of the pump <NUM> and the branch member <NUM>, respectively. There may be any number of the stent <NUM> and the receiving structure <NUM> including one, two, three, four, five, or more of each of the stent <NUM> and the receiving structure <NUM>. The number of receiving structure <NUM> and the number of stents <NUM> may be unequal in number. In certain instances, there may be a greater number of receiving structures <NUM> to facilitate docking of the stents <NUM>. In other instances, one or both of the stent <NUM> and the receiving structure <NUM> are discrete elements and the other of the stent <NUM> and the receiving structure <NUM> may be continuous. In certain instances, both the stent <NUM> and the receiving structure <NUM> are continuous. In addition, the stent <NUM> may be arranged on the internal surface of the branch member <NUM> and the receiving structure <NUM> may be arranged on the external surface of the pump <NUM>.

The stent <NUM> may be spring-like and may facilitate removal of the pump <NUM> from the branch member <NUM>. The pump <NUM> may include an engagement feature <NUM> that may be snared or grasped in removing the pump <NUM> from the branch member <NUM>. After gripping or grasping the engagement feature <NUM>, the pump <NUM> may be withdrawn and the elasticity of the stent <NUM> may temporarily collapse against the pump <NUM> and move past the receiving structure <NUM>.

<FIG> is an illustration of another example branch member <NUM>, pump <NUM>, anchor element, and receiving structure, according to some embodiments. In certain instances, the anchor element is a protrusion <NUM> and the receiving structure is a shaped notch <NUM> configured to contain the protrusion <NUM> may removably fix the pump <NUM> within the branch member <NUM>. The protrusion <NUM> may be arranged with the pump <NUM> and the shaped notch <NUM> may be arranged with the branch member <NUM>, as shown, protrusion <NUM> may be arranged with the branch member <NUM> and the shaped notch <NUM> may be arranged with the pump <NUM>.

The shaped notch <NUM> may be a j-shaped hook that facilitates torque locking between the branch member <NUM> and the pump <NUM>. The protrusion <NUM> may be arranged within the shaped notch <NUM> to releasably lock the branch member <NUM> and the pump <NUM> together.

In certain instances, the pump <NUM> is configured to facilitate engagement between the anchor element <NUM> and the notch <NUM>. As noted above with reference to <FIG>, the pump <NUM> is coupled to a controller. The controller may include options for different torques, speeds, rotations per minute (RPM), treatment schedules, or other parameters for the pump <NUM>. When initially arranged within the branch member <NUM>, a torque, speed, or RPMs may be selected that overcomes friction between the protrusion <NUM> and the shaped notch <NUM> to drive the protrusion <NUM> into locking engagement with the shaped notch <NUM>. In certain instances, the torque, speed, or RPMs may be higher than an operating torque, speed, or RPM to overcome friction between the protrusion <NUM> and the shaped notch <NUM> to drive the protrusion <NUM> into locking engagement with the shaped notch <NUM>.

<FIG> is an illustration of another example branch member <NUM>, pump <NUM>, anchor element, and receiving structure, according to some embodiments. In certain instances, the anchor element is a first threaded member <NUM> and the receiving structure is a second threaded member <NUM>. The first threaded member <NUM> and the second threaded member <NUM> may be oppositely threaded. In addition, the first threaded member <NUM> and the second threaded member <NUM> are configured to engage to removably fix the pump <NUM> within the branch member <NUM>. In other instances, the anchor element and the receiving structure may be magnetic instead of threaded features. In addition, the first threaded member <NUM> and the second threaded member <NUM> may be polymeric, balloon expandable, or self expanding.

In certain instances, the pump <NUM> is configured to facilitate engagement between the first threaded member <NUM> and the second threaded member <NUM>. As noted above with reference to <FIG>, the pump <NUM> is coupled to a controller. The controller may include options for different torques, speeds, or rotations per minute (RPM) for the pump <NUM>. When initially arranged within the branch member <NUM>, a torque, speed, or RPMs may be selected that threads of the first threaded member <NUM> and the second threaded member <NUM> are drive into locking engagement. In certain instances, the torque, speed, or RPMs may be higher than an operating torque, speed, or RPM to thread the first threaded member <NUM> and the second threaded member <NUM> together.

In certain instances, the pump <NUM> and the branch member <NUM> may be interference fit together. The anchor element <NUM> and the receiving structure <NUM> may be integral structures along a length of the branch member <NUM> and pump <NUM> to anchor the branch member <NUM> and pump <NUM> together. In addition, the anchor element <NUM> and the receiving structure <NUM> may be expandable elements to facilitate the friction or interference fit. In certain instances, the anchor element <NUM> and the receiving structure <NUM> are representative of a portion of the branch member <NUM> and pump <NUM> (e.g., sleeve, balloon, or swellable material) that expands after the pump <NUM> is pushed into place.

In addition and in certain instances, the branch member <NUM> (or pump <NUM>) may include a valve <NUM> at an outflow end of the branch member <NUM>. The valve <NUM> may close to prevent backflow through the pump <NUM> when the pump <NUM> is not in operation. The valve <NUM> may include a graft material, film, or a metal (e.g., Nitinol, stainless steel) or a combination thereof.

<FIG> is an illustration of a pump <NUM> and expandable braided structure <NUM>, according to some embodiments. The pump <NUM> is configured to deploy within the access site and to force blood flow through the pump <NUM> and into the lumen of the main body. The pump <NUM> includes an expandable braided structure <NUM> configured to removably fix the pump <NUM> within the main body. The braided structure <NUM> may be configured to expand within the main body that is implanted within an aorta <NUM>.

The braided structure <NUM> is configured to fixate the pump <NUM> within the main body or within the aorta <NUM> without the main body. The braided structure <NUM> may expand within a fenestration or portion of the main body. In certain instances, the braided structure <NUM> may expand to a diameter larger than the aorta <NUM>, vessel, main body, or portal into which the braided structure <NUM> is implanted. The braided structure <NUM> may also act as an integrated filter. In certain instances, the braided structure <NUM> may include a membrane.

The braided structure <NUM> may include a snaring element <NUM> configured to facilitate collapsing of the braided structure <NUM> in response to tension. The snaring element <NUM> may be formed by terminating ends of the braided structure <NUM> forming a ring or other snareable structure. In other instances, the snaring element <NUM> may be a loop or ball coupled to the braided structure <NUM>. Applying tension to the braided structure <NUM> collapses the braided structure <NUM> to enable removal and placement of the braided structure <NUM>.

<FIG> is an illustration of an example shunt <NUM> with flanges 520a, <NUM> and a driveline <NUM> arranged through the shunt <NUM>, according to some embodiments. Similar to the branch member <NUM> with flanges 520a, 520b discussed above with reference to <FIG>, the shunt <NUM> is configured to engage a tissue wall <NUM>. The tissue wall <NUM> may be the septum of a patient's hear tor along another portion of the heart wall. In certain instances, the shunt <NUM> is configured to provide a lumen <NUM> for a driveline <NUM>.

The shunt <NUM>, as shown in <FIG>, may be positioned at a location along the tissue wall <NUM> of heart for the driveline <NUM> to cross and connect to a controller <NUM>, as described in detail above, at one end, with the other end connected to a pump <NUM>. In certain instances, the pump <NUM> may be located in another portion of the heart (e.g., left atrium connecting to the aorta) without an over docking mechanism such as the branch member <NUM> or other anchor system. In these instances, the shunt <NUM> may be used to anchor the driveline <NUM>.

In certain instances, the lumen <NUM> is sized equal to or substantially equal to a circumference of the drive <NUM>. In this manner, leakage does not occur through the lumen <NUM>. The lumen <NUM> being sized equal to or substantially equal to a circumference of the driveline <NUM> allows for anchoring therein by, for example, a fiction or interference fit. The shunt <NUM> may be formed of a graft, a support structure (such as stent), or a combination thereof. In certain instances, the shunt <NUM> may be a coil of wire or film that may tighten about the driveline <NUM>. In certain instances, the pump <NUM> may be directly or indirectly coupled to the shunt <NUM> as is explained in further detail below. In certain instances, the pump <NUM> being directly or indirectly coupled to the shunt <NUM> may establish a fluidic connection therebetween.

In certain instances, the flanges 520a, 520b may include a barrel portion <NUM> that connects that flanges 520a, 520b. The flanges 520a, 520b and the barrel portion <NUM> may be a uniform structure, in certain instances, and in other instances, the flanges 520a, 520b and the barrel portion <NUM> may be separate structures coupled to attached together prior to implantation. Similar to the branch member <NUM>, the flanges 520a, 520b and the barrel portion <NUM> may include stent components, graft components, or a combination of stent and graft components.

<FIG> is an illustration of another implantable medical device for cardiac assistance in a delivery configuration, according to some embodiments. As shown in <FIG>, a pump <NUM> is arranged in a collapsed configuration for delivery. The pump <NUM> includes one or more flanges 520a, 520b (one flange is shown on an end of the pump <NUM> for ease of illustration), as is described in detail above. The flange 520a is collapsed toward the pump <NUM> in the delivery configuration. In certain instances, the flange 520a is held in the collapsed configuration by a lock wire <NUM> or similar mechanism. As shown, an end portion <NUM> of the lock wire <NUM> may be wrapped about the flange 520a. The flange 520a may be release by pulling back on the lock wire <NUM>. In certain instances, the flange 520a may be held within a nose cone <NUM> rather than or in addition to the lock wire <NUM>.

During delivery, the pump <NUM> and flange 520a is delivered, and when satisfactory positioning is achieved (e.g., within branch member <NUM>), the lock wire <NUM> and/or the nose cone <NUM> is released.

In certain instances, the pump <NUM> and flange 520a may be arranged such that the flange 520a anchors the pump <NUM> within the atrial septum. The pump <NUM> may then be arranged across the pulmonary vein and configured to pull blood from the vein (and/or left atrium) thru the pump <NUM> for increased blood flow. The pump <NUM> may be arranged within a branch member <NUM> and within the pulmonary vein as is described in further detail above with reference to <FIG>. An opposite end of the pump <NUM> (the side not anchored within the pulmonary vein) may extend into the aorta as also described in detail above.

<FIG> is an illustration of a pump <NUM> and delivery sheath <NUM>, according to some embodiments. The pump <NUM> includes anchor elements <NUM> extending from an exterior surface of the pump <NUM>. The anchor elements <NUM>, as shown in <FIG>, are s-hook elements that fit around or are integrated with the pump <NUM>. The anchor elements <NUM> may be configured to either interference or friction fit the pump <NUM> within a branch member <NUM>, or the branch member <NUM> may include a receiving structure as described in detail above (e.g., <FIG>).

In certain instances, a delivery sheath <NUM> may depress or crush the anchor elements <NUM> against the pump <NUM> to allow for the pump <NUM> to deploy and/or be removed from the branch member <NUM>.

In certain instances, a lock wire <NUM> may be arranged with and coupled to the pump <NUM>. The lock wire <NUM> may be extend along the driveline <NUM>. the lock wire <NUM> may form a portion of or can be integral with the driveline <NUM>, or the lock wire <NUM> may be arranged within the driveline <NUM>. The lock wire <NUM> may be pulled back to via the driveline <NUM> or separately from the driveline <NUM> to remove the pump <NUM>. The pump <NUM> may be replaced or a new pump <NUM> may be reinstalled to continue functionality of the cardiac assistance device. Pulling on the lock wire <NUM> overcomes the anchor elements <NUM> and may remove the pump <NUM> from the branch member <NUM>.

A biocompatible material for the graft components or membrane components, discussed herein, may be used. In certain instances, the graft may include a fluoropolymer, such as a polytetrafluoroethylene (PTFE) polymer or an expanded polytetrafluoroethylene (ePTFE) polymer. In some instances, the graft may be formed of a polyester, a silicone, a urethane, a polyethylene terephthalate, or another biocompatible polymer, or combinations thereof. In some instances, bioresorbable or bioabsorbable materials may be used, for example a bioresorbable or bioabsorbable polymer. In some instances, the graft can include Dacron, polyolefins, carboxy methylcellulose fabrics, polyurethanes, or other woven or film elastomers.

In addition, nitinol (NiTi) may be used as the material of the frame or stent (and any of the frames discussed herein), but other materials such as stainless steel, L605 steel, polymers, MP35N steel, polymeric materials, Pyhnox, Elgiloy, or any other appropriate biocompatible material, and combinations thereof, can be used as the material of the frame. The super-elastic properties and softness of NiTi may enhance the conformability of the stent. In addition, NiTi can be shape-set into a desired shape. That is, NiTi can be shape-set so that the frame tends to self-expand into a desired shape when the frame is unconstrained, such as when the frame is deployed out from a delivery system.

Claim 1:
An implantable medical device for cardiac assistance, the implantable medical device comprising:
a main body (<NUM>) configured to be disposed within the aorta (<NUM>), the main body including a lumen operable to convey blood through the aorta; the implantable medical device being characterised by an access site (<NUM>) in a sidewall of the main body operable to provide access to the lumen of the main body; and by
a branch member (<NUM>) configured to be disposed within the access site to fluidly connect with the lumen of the main body, the branch member includes one or more anchor elements (<NUM>) configured to interface with and secure a pump (<NUM>) with the branch member