Patent Description:
This disclosure relates generally to medical devices, and more specifically, to inflow or outflow cannulas that may include a tissue anchor.

Cannulas may be able to create flow conduits within a patient. For example, cannulas may be used to create flow conduits to or from an organ such as the heart. A cannula may be used to create an inflow or outflow conduit from the heart. In certain instances, a cannula may be used to create an inflow conduit from the heart in cardiac assist applications to increase blood from the heart to assist with blood circulation in a patient. Arranging the cannula within an organ such as the heart may use an anchoring structure. <CIT> describes a cannula assembly for directing the flow of material from an organ chamber, e.g., blood from the left chamber of the heart, and methods of placing the cannula assembly in fluidic communication with the chamber. The cannula assembly includes an elongate tubular member and a coupling assembly disposed at the distal end of elongate tubular member. The elongate tubular member includes a lumen extending from a distal opening at the distal end to a proximal opening at the proximal end. The coupling assembly includes a retaining element and a retention member configured to cooperate with each other and with the portion of the organ wall surrounding the opening in the wall to couple or anchor cannula system to the wall and to provide fluidic communication between the distal opening of the elongate tubular member and the organ chamber.

The claimed invention proposes a cannula apparatus according to claim <NUM> (Example <NUM>). Optional features are mentioned in the dependent claims <NUM>-<NUM> :.

According to another example ("Example <NUM>"), further to the apparatus of Example <NUM>, the graft portion is arranged on an exterior surface and an interior surface of the plurality of elongate members.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the graft portion is arranged along an interior surface of the plurality of elongate members and extends along the interior surface of the conduit to a second end of the conduit.

According to another example ("Example <NUM>"), further to the apparatus of Example <NUM>, the graft portion extends along an exterior surface of the plurality of elongate members.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the inlet portion is configured to conform to the tissue wall and lessen tissue erosion thereof.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the exterior surface of the conduit is configured to lessen thrombus formation.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the inlet portion includes a funnel shape in an initial configuration and is configured to flatten and deploy against the tissue wall.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the apparatus also includes a constraining ring arranged about the plurality of elongate members to maintain the inlet portion in a substantially cylindrical configuration and allow release of the inlet portion to flatten and deploy against the tissue wall.

According to another example ("Example <NUM>"), further to the apparatus of Example <NUM>, the constraining ring is configured to slide away from the first end of the conduit in response to contact with an epicardial surface of the heart to allow release of the inlet portion.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the apparatus also includes a plurality of ring structures arranged along the exterior surface of an outflow portion of the conduit.

According to another example ("Example <NUM>"), further to the apparatus of any one of Examples <NUM>-<NUM>, the inlet portion is configured to deploy against the tissue wall in response to fluid flow pressure with a heart chamber. While multiple examples of the claimed invention are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative examples. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature rather than restrictive in nature. The scope of the claimed invention is only limited by the claims.

This disclosure is not meant to be read in a restrictive manner. For example, the terminology used in the application should be read broadly in the context of the meaning those in the field would attribute such terminology.

With respect to terminology of inexactitude, the terms "about" and "approximately" may be used, interchangeably, to refer to a measurement that includes the stated measurement and that also includes any measurements that are reasonably close to the stated measurement. Measurements that are reasonably close to the stated measurement deviate from the stated measurement by a reasonably small amount as understood and readily ascertained by individuals having ordinary skill in the relevant arts. Such deviations may be attributable to measurement error, differences in measurement and/or manufacturing equipment calibration, human error in reading and/or setting measurements, minor adjustments made to optimize performance and/or structural parameters in view of differences in measurements associated with other components, particular implementation scenarios, imprecise adjustment and/or manipulation of objects by a person or machine, and/or the like, for example. In the event it is determined that individuals having ordinary skill in the relevant arts would not readily ascertain values for such reasonably small differences, the terms "about" and "approximately" can be understood to mean plus or minus <NUM>% of the stated value.

Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of methods and apparatuses configured to perform the intended functions. 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 apparatuses, systems, and methods that may be used in improving or assisting the cardiac function of the heart. The disclosed to apparatuses, systems, and methods generally include an anchoring structure or inlet portion of a cannula that may be arranged within a patient's heart. The disclosed anchoring structure or inlet portion of a cannula may be used with a pump system for increasing blood flow in a patient.

<FIG> is an illustration of an example anchoring structure <NUM>, in accordance with various aspects of the present disclosure. The anchoring structure <NUM> may be used for an inflow or outflow cannula. The anchoring structure <NUM> includes an inlet portion <NUM> including a plurality of elongate members <NUM> arranged about a circumference of the inlet portion <NUM>. The plurality of elongate members <NUM> configured to deploy against a tissue wall (e.g., as shown in <FIG>).

The anchoring structure <NUM> also includes an outflow portion <NUM> arranged distal of the inlet portion <NUM> and including an exterior surface and an interior surface. A graft portion <NUM> may cover and be arranged between the plurality of elongate members <NUM> as is shown in <FIG>. In addition, the graft portion <NUM> extends along an interior surface of the outflow portion <NUM>. The graft portion <NUM> being arranged along an interior portion of the inlet portion <NUM> and the outlet portion <NUM> may lessen thrombus formation along the interior surface. The interior surface is the luminal surface for blood flow when the anchoring structure <NUM> is arranged within the patient. The graft portion <NUM> extending along the interior surface of the inflow portion <NUM> and the outflow portion <NUM> may lessen surface disturbances along the blood flow surface of the anchoring structure <NUM>.

In certain instances, the graft portion <NUM> may also extend about a distal end of the inlet portion <NUM> and cover an exterior surface of the inlet portion <NUM>. In other instances, a second graft portion or layer may extend to cover the exterior surface of the inlet portion <NUM>. The graft portion <NUM> may extend between and within the spaces of the plurality of elongate members <NUM>. In certain instances, the graft portion <NUM> may be configured to stretch and recover in response to forces acting on the graft portion <NUM>. The stretching may facilitate conformability. For further discussion regarding the material properties of the graft portion <NUM>, reference may be made to <CIT>").

As shown, the inlet portion <NUM> may include a funnel shape in an initial configuration. The plurality of elongate members <NUM> may be shape set in the funnel shape in certain instances. The inlet portion <NUM> may be configured to flatten and deploy against the tissue wall. In certain instances, the inlet portion <NUM> is configured to deploy against the tissue wall in response to fluid flow pressure with a heart chamber.

As discussed in further detail below, the anchoring structure <NUM> may be arranged with an outflow or inflow cannula and coupled to a pump. The anchoring structure <NUM> may contact the tissue wall of a patient's heart and stabilize the cannula. The anchoring structure <NUM> is configured to contact and conform to the tissue wall and provide an inlet for blood flow out of the heart. The anchoring structure <NUM> may lessen stasis and thrombus formation by maintaining contact against the tissue wall as discussed in further detail below. The plurality of elongate members <NUM> may stabilize the anchoring structure <NUM> and the graft portion <NUM> may cover the entirety of the plurality of elongate members <NUM> to lessen tissue erosion.

<FIG>are example cut-patterns for inlet portions, in accordance with various aspects of the present disclosure. A plurality of elongate members <NUM> may be formed from any one of or a combination of the cut-patterns shown in <FIG>. The plurality of elongate members <NUM> may be formed from a flat-sheet or tube of Nitinol (NiTi). In certain instances, the plurality of elongate members <NUM> may be formed of a polymer material or a different biocompatible metal such as stainless steel. The plurality of elongate members <NUM> may include an atraumatic distal end <NUM>. The distal end <NUM> of each of the plurality of elongate members <NUM> may be curved.

In addition, the patterns that form the plurality of elongate members <NUM> may be formed into an inlet portion or anchoring structure as shown in <FIG> and <FIG>, for example, the number of plurality of elongate members <NUM> may vary as shown in <FIG>. For example, the pattern shown in <FIG> includes <NUM> elongate members <NUM> and the pattern shown in <FIG> includes <NUM> elongate members <NUM>. Patterns may be formed to include <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or any number therebetween number of elongate members <NUM>.

In addition and as shown, the patterns include a shoulder portion <NUM> that the plurality of elongate members <NUM> extend from. The height or length may be varied as shown in comparing the patterns shown in <FIG>. In addition, the spacing between the elongate members <NUM> may be varied as shown in comparing the patterns shown in <FIG>. The thickness of the tube or flat sheet used to form the elongate members <NUM> may be between. <NUM> thick. In addition, the patterns may be formed into a funnel structure, as shown in <FIG> and <FIG>, to include approximately a <NUM> to <NUM> outer diameter. A three dimensional form of the patterns is shown, for example, in <FIG>.

<FIG> is an illustration of an example cannula <NUM>, in accordance with various aspects of the present disclosure. The cannula <NUM> may be used as an inflow or outflow cannula apparatus. The cannula <NUM> may include a conduit <NUM> having an exterior surface and an interior surface. The cannula <NUM> may also include an inlet portion <NUM> arranged at a first end of the conduit <NUM>. The inlet portion <NUM> may include a plurality of elongate members <NUM> arranged about a circumference of the inlet portion <NUM> that are configured to deploy against a tissue wall.

The cannula <NUM> may also include a graft portion <NUM> covering and arranged between the plurality of elongate members <NUM> and extending along the interior surface of the conduit <NUM>. In certain instances, the graft portion <NUM> is arranged on an exterior surface and an interior surface of the plurality of elongate members <NUM>. In addition, the graft portion <NUM> may be arranged along an interior surface of the plurality of elongate members <NUM> and extend along the interior surface of the conduit <NUM> to a second end <NUM> (or outflow portion) of the conduit. The graft portion <NUM> may also extend along an exterior surface of the plurality of elongate members <NUM>.

The inlet portion <NUM> may contact the tissue wall of a patient's heart and stabilize the cannula <NUM>. The inlet portion <NUM>, by way of the elongate members <NUM> and the graft portion <NUM>, may be configured to contact and conform to the tissue wall and provide an inlet for blood flow out of the heart. The inlet portion <NUM> may lessen stasis and thrombus formation by maintaining contact against the tissue wall as opposed to extending into the heart. The plurality of elongate members <NUM> may stabilize the anchoring structure <NUM> and the graft portion <NUM> may cover the entirety of the plurality of elongate members <NUM> to lessen tissue erosion.

As shown, the inlet portion <NUM> includes a funnel shape in an initial configuration and is configured to flatten and deploy against a tissue wall (e.g., as shown in <FIG>). The inlet portion <NUM> is configured to deploy against the tissue wall in response to fluid flow pressure with a heart chamber. In addition and as noted above, the graft portion <NUM> may be arranged along an interior surface of the plurality of elongate members <NUM> and extend along the interior surface of the conduit <NUM>. The graft portion <NUM> being arranged along an interior portion of the inlet portion <NUM> and the conduit <NUM> may lessen thrombus formation along the interior surface. The interior surface is the luminal surface for blood flow within the cannula <NUM>. The graft portion <NUM> extending along the interior surface of the inflow portion <NUM> and the conduit <NUM> may lessen surface disturbances along the blood flow surface of the cannula <NUM>.

A plurality of ring structures <NUM> arranged may be along the exterior surface of an outflow portion <NUM> of the conduit <NUM>. The plurality of ring structures <NUM> may be a biocompatible non-metallic material such as densified ePTFE. For further discussion to densified ePTFE, reference may be made to <CIT>") and <CIT>"). The plurality of ring structures <NUM> may facilitate kink resistance and hoop strength of the outflow portion <NUM> of the conduit <NUM>.

In certain instances, the graft portion <NUM> may include a coating that is configured to minimize a thrombogenic response that may occur due to exposure of the graft portion <NUM> to blood contact. In certain instances, the coating may be a heparin coating. The heparin coating is utilized to bind heparin molecules to the graft portion <NUM>. For further discussion regarding a heparin coated graft portion <NUM>, reference may be made to <CIT>") for the specific teachings of antithrombogenic activity of surface immobilized heparin. In certain instances, the heparin coating may be CARMEDA® BioActive Surface (CBAS® Heparin Surface).

In certain instances, the heparin coating may be applied to the graft portion <NUM> in one or more layers. The chemical constituents of the covering material in each layer can be the same or different. In some instances, the covering material is cross-linked to itself or other covering materials in other layers. The cross-linking bonds can be covalent or ionic. The heparin covering may form at least one layer on at least a portion of the graft portion <NUM> and may cross-link to itself or other layers of the covering. The cross-linking can be covalent, ionic, or both. For reference regarding the application of layers of heparin to the graft portion <NUM>, reference may be made to <CIT>).

In some instances, the graft portion <NUM> is configured to induce rapid tissue ingrowth therein on at least a portion of an exterior (tissue contacting) surface. In these instances, the configuration or material properties of the graft portion <NUM> covering the exterior surface of the inlet portion <NUM> may be different than properties of the interior graft portion <NUM>. The graft portion <NUM> may be different layers of the same graft portion <NUM> or the exterior may include a different second graft portion. For ingrowth, the graft portion <NUM> can have a microporous structure that provides a tissue ingrowth scaffold for durable occlusion and supplemental anchoring strength of plurality of elongate members <NUM>.

In certain instances, the cannula <NUM> may include a coupling section <NUM>. The coupling section <NUM> may be used to seal and secure the cannula <NUM> with an opening created in the tissue. For example, an opening may be created in the heart (ventricle or atrium) when the cannula <NUM> is arranged therein. The inlet portion <NUM>, as noted above, is arranged on an interior wall of the heart tissue (as also shown in <FIG>). The coupling section <NUM> may seal the opening and hold the cannula <NUM> in place. In certain instances, sutures may be arranged through the coupling section <NUM> to secure the coupling section <NUM> to the heart tissue.

<FIG> is an illustration of an example inlet portion <NUM> arranged within heart tissue <NUM>, in accordance with various aspects of the present disclosure. The inlet portion <NUM> includes a plurality of elongate members <NUM> with a graft portion <NUM> attached to an exterior surface (contacting the tissue wall <NUM>) and an interior surface (shown in <FIG>). As discussed in detail above, the graft portion <NUM> covers spaces or gaps between the elongate members <NUM>.

As shown in <FIG>, the inlet portion <NUM> contacts the tissue wall <NUM> in a deployed configuration. The inlet portion <NUM>, by way of the elongate members <NUM> and the graft portion <NUM>, may be configured to contact and conform to the tissue wall and provide an inlet for blood flow out of the heart. The inlet portion <NUM> may lessen stasis and thrombus formation by maintaining contact against the tissue wall as opposed to extending into the heart. The plurality of elongate members <NUM> may stabilize the anchoring structure <NUM> and the graft portion <NUM> may cover the entirety of the plurality of elongate members <NUM> to lessen tissue erosion. The tissue wall <NUM> may be within the heart (e.g., left ventricle, left atrium, right ventricle, right atrium) in certain instances. In addition, the anchoring structure <NUM> may be arranged within an appendage of the heart (e.g., left atrial appendage).

In addition and as is shown, the graft portion <NUM> may be arranged along an interior surface of the plurality of elongate members <NUM> and extend along an interior surface <NUM> of a conduit <NUM> to a second end (or outflow portion) of the conduit.

<FIG> is an example system that includes an inflow cannula <NUM>, an outflow cannula <NUM>, and a pump <NUM>, in accordance with various aspects of the present disclosure. As described in detail above, the inflow cannula <NUM> may include an inlet portion <NUM>, and may be coupled to a pump <NUM> at an outflow portion <NUM>.

The pump <NUM> may generally be any pump <NUM> that is configured to drive or otherwise cause blood to flow across the pump <NUM> through the cannula <NUM> from the inlet portion <NUM> to and through the outflow cannula <NUM>. The outflow cannula <NUM>, as shown, may include a plurality of ring structures <NUM> to facilitate kink resistance and hoop strength as noted above with reference to the ring structures <NUM> on the inflow cannula <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, a positive displacement pump, a pulsatile pump, or other similar device such as a worm-style drive mechanism, or impeller. The pump <NUM> can be operated to draw blood from the left ventricle (or other heart chamber) and across the pump <NUM>.

In certain instances, the system 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 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 battery to control operation of the pump <NUM>. In certain instances, the controller <NUM> may be integrated into the pump <NUM> such that the system may be configured to operate without the need for the driveline <NUM>, or the driveline <NUM> need not extend extracorporeally.

In addition, 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 some examples, the pump <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.

<FIG> is a side view of an example inlet portion <NUM> and a constraining ring <NUM> in a delivery configuration; in accordance with various aspects of the present disclosure. As shown, the inlet portion <NUM> (which includes a plurality of elongate members <NUM> and a graft portion <NUM>) is constrained and maintained in a substantially cylindrical configuration/shape in the delivery configuration by the constraining ring <NUM>. <FIG> is a top view of the inlet portion <NUM> and the constraining ring <NUM>, shown in <FIG>, in the delivery configuration, in accordance with various aspects of the present disclosure;.

The constraining ring <NUM> may be configured to slide away from the inlet end of the conduit <NUM> (e.g., the inlet end) in response to contact with an epicardial surface of the heart to allow release of the inlet portion. <FIG> is a side view of the inlet portion <NUM> and the constraining ring <NUM>, shown in <FIG>, in a second configuration where the constraining ring <NUM> has been slid to release the inlet portion <NUM>. In certain instances, the inlet portion <NUM> (e.g., the anchoring structure) is arranged within a patient's heart in the delivery configuration shown in <FIG>. The inlet portion <NUM> (e.g., the anchoring structure) is moved within the heart, and the inlet portion <NUM> is allowed to expand from the delivery configuration to deploy against the tissue wall. An opening or hole in the heart (or other tissue) may be formed prior to moving the inlet portion <NUM> within the heart. The constraining ring <NUM>, in certain instances, may contact an exterior surface of the heart or organ and slide away from an end of the inlet portion <NUM> to allow release of the inlet portion <NUM> to flatten and deploy against the tissue wall (e.g., as shown in <FIG>).

Moving the inlet portion <NUM> includes forcing the constraining ring <NUM> against an epicardial surface of the heart to allow release of the inlet portion <NUM>, in certain instances. The opening created in the heart tissue may be smaller than an outer diameter of the constraining ring <NUM> to ensure that the constraining ring <NUM> does not enter the heart. In certain instances, an actuator or line may be coupled to the constraining ring <NUM> such that a physician may manually actuate the constraining ring <NUM>.

<FIG> show various configurations of a cannula <NUM> and inlet portion <NUM> consistent with the various aspects of the present disclosure. The aspects of the inlet portions <NUM> differing between <FIG> generally relates to a number of elongate members as described in detail above.

<FIG> is a perspective view of an example adjustable cannula portion <NUM>, in accordance with various aspects of the present disclosure. The adjustable cannula portion <NUM> may form a portion of a cannula <NUM> (e.g., an inflow or outflow) as discussed in detail above. The adjustable cannula portion <NUM> may include a stop <NUM> that may move along a length of the adjustable cannula portion <NUM>. In certain instances, at least a portion of an outer surface of the adjustable cannula portion <NUM> may be a threaded surface <NUM>. The stop <NUM> may travel along a length of the threaded surface <NUM>. The stop <NUM> may be positioned at a desired location along the threaded surface <NUM> to adjust an amount of the adjustable cannula portion <NUM> that is arranged within a patient's heart.

In certain instances, an inlet portion <NUM> (as discussed in detail above) may be arranged at a first end <NUM> of the adjustable cannula portion <NUM>. A conduit <NUM> (as discussed in detail above) may form a portion of the adjustable cannula portion <NUM> a second end <NUM> of the adjustable cannula portion <NUM>.

<FIG> is a side view of an example adjustable cannula portion <NUM> and inlet portion <NUM> in a first configuration, in accordance with the claimed invention. <FIG> is a side view of the adjustable cannula portion <NUM> and inlet portion <NUM>, shown in <FIG>, in a second configuration. As shown in comparing <FIG>, a stop <NUM> is arranged along a length of the adjustable cannula portion <NUM> along a threaded surface <NUM>.

In certain instances, the closer the stop <NUM> is arranged to the inlet portion <NUM>, the less the inlet portion <NUM> is arranged within the heart. For example and as shown in <FIG>, a tissue wall <NUM> is arranged between the inlet portion <NUM> and the stop <NUM>. The closer the stop <NUM> is arranged to the inlet portion <NUM>, the less amount of tissue wall <NUM> is arranged between the inlet portion <NUM> and the stop <NUM>. The slope of the tissue wall <NUM> may influence the desired location of the stop <NUM> along the threaded surface <NUM>. The adjustable cannula portion <NUM> may facilitate or allow for a desired position of the inlet portion <NUM> such that the cannula does not substantially protrude within the heart. In certain instances, the customizable length may facilitate lessening of stasis and thrombus formation by maintaining contact of the inlet portion <NUM> against the tissue wall as opposed to extending into the heart. The stop <NUM> is configured to travel along a length of the threaded surface <NUM> to adjust a position of the inlet portion <NUM> relative to the tissue wall <NUM>. The threaded surface <NUM> or other portion of the adjustable cannula portion <NUM> and/or the stop <NUM> may include a locking feature (e.g., tabs, frictional engagement members) to hold and/or lock the stop 1102in place along the threaded surface <NUM>.

A biocompatible material for the graft 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, such as, but not limited to, 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, non-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, but not limited to, 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.

In certain instances, the coating, as discussed in detail above, may include bio-active agents in addition to heparin or alternatively to heparin. The agents can include, but are not limited to, vasodilator, anti-coagulants, anti-platelet, antithrombogenic agents.

Claim 1:
An inflow or outflow cannula apparatus (<NUM>), the apparatus comprising:
a conduit (<NUM>) having an exterior surface and an interior surface;
an inlet portion (<NUM>) arranged at a first end of the conduit including a plurality of elongate members (<NUM>) arranged about a circumference of the inlet portion (<NUM>) configured to deploy against a tissue wall;
and
a graft portion (<NUM>) covering and arranged between the plurality of elongate members (<NUM>) and extending along the interior surface of the conduit (<NUM>), the inflow or outflow cannula apparatus being characterized in that the conduit includes an adjustable cannula portion (<NUM>) having a threaded surface (<NUM>) and a stop (<NUM>), and the stop is configured to travel along a length of the threaded surface (<NUM>) to adjust a position of the inlet portion (<NUM>) relative to the tissue wall.