Patent Description:
Circulatory support devices support the pumping action of the heart. These devices may be disposed through a valve opening such as, for example, an aortic valve. Blood flow through the circulatory support devices is an important factor when differentiating between different types of circulatory support devices.

<CIT> discloses a pump for inducing flow within a vascular system, the pump comprises a cannula having a first configuration for deployment within the vascular system and a second configuration for directing the fluid flow within the vascular system, where the second configuration has a greater diameter than the first configuration. An impeller is configured to induce the fluid flow through the cannula by rotation about an axis. The impeller has a first radius in the first configuration and a second radius in the second configuration, where the second radius is greater than the first radius.

Embodiments disclosed herein relate to circulatory support devices that have an increased flow capability in comparison to conventional embodiments. Exemplary embodiments include, but are not limited, to the following examples.

In an Example <NUM>, an apparatus for attachment to a cardiac pump, the apparatus comprises: an adaptor comprising: an annular cross section configured to receive the cardiac pump, wherein the annular cross section is secured to the cardiac pump; and a plurality of channels arranged around the adapter; a cannula comprising a proximal portion, a distal portion, and an intermediate portion comprising a braided mesh extending between the distal portion and the proximal portion, the proximal portion having a proximal end comprising a plurality of elements arranged through the channels and the distal portion comprising a plurality of wires and a tip element, wherein the plurality of wires extend in a distal direction from the braided mesh to the tip element, wherein the plurality of wires are secured to the tip element; and a coating covering at least a portion of the braided mesh.

In an Example <NUM>, the apparatus of Example <NUM>, wherein a proximal portion of the braided mesh comprises a tapered portion that increases in diameter from a proximal end of the tapered portion to a distal end of the tapered portion.

In an Example <NUM>, the apparatus of any one of Examples <NUM> or <NUM>, wherein the braided mesh comprises a constant pitch.

In an Example <NUM>, the apparatus of any one of Examples <NUM> or <NUM>, wherein the braided mesh comprises a varying pitch.

In an Example <NUM>, the apparatus of any one of Examples <NUM>-<NUM>, wherein the channels extend along an interior surface of the adaptor.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the channels extend along an entire length of the adaptor.

In an Example <NUM>, the apparatus of any one of Examples <NUM>-<NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and a plurality of elongate members extending from the distal cylindrical portion to the proximal cylindrical portion, wherein conduits extending through a thickness of the adaptor separate each of the elongate members.

In an Example <NUM>, the apparatus of any one of Examples <NUM>-<NUM>, wherein at least one of the plurality of channels extends longitudinally.

In an Example <NUM>, the apparatus of any one of Examples <NUM>-<NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and one or more intermediate cylindrical portions extending between the distal cylindrical portion and the proximal cylindrical portion, wherein the intermediate cylindrical portion has a smaller diameter than the distal cylindrical portion, and wherein the channels extend through a length of the distal cylindrical portion.

In an Example <NUM>, the apparatus of any one of Examples <NUM>-<NUM>, wherein the plurality of elements arranged through the channels are a plurality of loop elements.

In an Example <NUM>, a method for manufacturing an apparatus for attachment to a cardiac pump, the method comprises: arranging proximal ends of a plurality of wires through a plurality of channels of an adaptor; braiding an intermediate portion of the plurality of wires to create a braided mesh; extending a distal portion of the plurality of wires in a distal direction; coating at least a portion of the braided mesh; and coupling a distal end of the distal portion to a tip element.

In an Example <NUM>, the method of Example <NUM>, wherein the braided mesh comprises a constant pitch.

In an Example <NUM>, the method of Example <NUM>, wherein the braided mesh comprises a varying pitch.

In an Example <NUM>, the method of any one of Examples <NUM>-<NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and a plurality of elongate members extending from the distal cylindrical portion to the proximal cylindrical portion, wherein conduits extending through a thickness of the adaptor separate each of the elongate members, and wherein arranging proximal ends of the plurality of wires through the plurality of channels comprises arranging the proximal ends through the conduits.

In an Example <NUM>, the method of any one of Examples <NUM>-<NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and one or more intermediate cylindrical portions extending between the distal cylindrical portion and the proximal cylindrical portion, wherein the intermediate cylindrical portion has a smaller diameter than the distal cylindrical portion, wherein the channels extend through a length of the distal cylindrical portion, and wherein arranging proximal ends of the plurality of wires through the plurality of channels comprises arranging the proximal ends through the channels.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the braided mesh comprises a constant pitch.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the braided mesh comprises a varying pitch.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the channels extend along an interior surface of the adaptor.

In an Example <NUM>, the apparatus of Example <NUM>, wherein at least one of the plurality of channels extends longitudinally.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and a plurality of elongate members extending from the distal cylindrical portion to the proximal cylindrical portion, wherein conduits extending through a thickness of the adaptor separate each of the elongate members.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the elongate members extend along an interior surface of the distal cylindrical portion, the proximal cylindrical portion, or both.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the elongate members extend along an entire length of the distal cylindrical portion, the proximal cylindrical portion, or both.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and one or more intermediate cylindrical portions extending between the distal cylindrical portion and the proximal cylindrical portion, wherein the intermediate cylindrical portion has a smaller diameter than the distal cylindrical portion, and wherein the channels extend through a length of the distal cylindrical portion.

In an Example <NUM>, the apparatus of Example <NUM>, wherein the plurality of elements are a plurality of loop elements.

In an Example <NUM>, a method for manufacturing an apparatus, the method comprises: arranging proximal ends of a plurality of wires through a plurality of channels of an adaptor; braiding an intermediate portion of the plurality of wires to create a braided mesh; extending a distal portion of the plurality of wires in a distal direction; coating at least a portion of the braided mesh; and coupling a distal end of the distal portion to a tip element.

In an Example <NUM>, the method of Example <NUM>, wherein braiding the intermediate portion comprises forming a tapered portion that increase in diameter from a proximal end of the tapered portion to a distal end of the tapered portion.

In an Example <NUM>, the method of Example <NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and a plurality of elongate members extending from the distal cylindrical portion to the proximal cylindrical portion, wherein conduits extending through a thickness of the adaptor separate each of the elongate members, and wherein arranging proximal ends of the plurality of wires through the plurality of channels comprises arranging the proximal ends through the conduits.

In an Example <NUM>, the method of Example <NUM>, wherein the adaptor comprises a distal cylindrical portion, a proximal cylindrical portion, and one or more intermediate cylindrical portions extending between the distal cylindrical portion and the proximal cylindrical portion, wherein the intermediate cylindrical portion has a smaller diameter than the distal cylindrical portion, wherein the channels extend through a length of the distal cylindrical portion, and wherein arranging proximal ends of the plurality of wires through the plurality of channels comprises arranging the proximal ends through the channels.

In an Example <NUM>, the method of Example <NUM>, further comprising attaching the adaptor to the cardiac pump.

In an Example <NUM>, the method of Example <NUM>, wherein the coating is silicone.

While multiple embodiments are disclosed, still other embodiments of the presently disclosed subject matter will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosed subject matter.

While the disclosed subject matter is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the subject matter disclosed herein to the particular embodiments described. On the contrary, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the scope of the subject matter disclosed herein, and as defined by the appended claims.

Embodiments disclosed herein include circulatory support devices that have an increased flow capability in comparison to conventional embodiments.

<FIG> depicts a conceptual diagram of a circulatory support device <NUM> including a cannula <NUM> and an adaptor <NUM>, in accordance with embodiments of the subject matter disclosed herein. The circulatory support device <NUM> is shown arranged within a heart <NUM>. According to embodiments, the circulatory support device <NUM> may include a ventricular assist device (shown in <FIG>), such as a pump, that is coupled to the cannula <NUM> by the adaptor <NUM>. The ventricular assist device is configured to pump blood from the subject's left ventricle <NUM> into the subject's aorta <NUM>. In embodiments, the circulatory support device <NUM> may be used to treat cardiogenic shock and other heart failure modalities.

In embodiments, a distal portion <NUM> of the circulatory support device <NUM> is arranged in the left ventricle <NUM>. An intermediate portion <NUM> of the circulatory support device <NUM> extends through the aortic valve <NUM> so that a proximal portion <NUM> of the cannula <NUM> extends into the aorta <NUM>. In embodiments, the proximal portion <NUM> of the cannula <NUM> is coupled to the adaptor <NUM> and the adaptor <NUM> is coupled to the circulatory support device <NUM>. During operation, the circulatory support device <NUM> draws blood from the left ventricle <NUM>, through the cannula <NUM> of the circulatory support device <NUM> and is released into the aorta <NUM>. Additionally, or alternatively, the circulatory support device <NUM> may be used to facilitate pumping blood from some other aspect of the subject's vasculature into an adjacent portion of the vasculature.

<FIG> is not intended to suggest any limitation as to the scope of use or functionality of embodiments of the present disclosure. <FIG> also should not be interpreted as having any dependency or requirement related to any single component or combination of components illustrated therein. Additionally, various components depicted in <FIG> may be, in embodiments, integrated with various ones of the other components depicted therein (and/or components not illustrated), all of which are considered to be within the ambit of the present disclosure.

<FIG> depicts a side view of the circulatory support device <NUM> depicted in <FIG> including the ventricular assist device <NUM>, in accordance with embodiments of the subject matter disclosed herein.

As stated above, the cannula <NUM> may include a proximal portion <NUM>, an intermediate portion <NUM>, and a distal portion <NUM>. The intermediate portion <NUM> may include a braided mesh <NUM> that extends between the proximal portion <NUM> and the distal portion <NUM>. In embodiments, the braided mesh <NUM> may have various braid angles and/or varying braid angles, as explained in more detail below. In embodiments, a proximal portion <NUM> of the braided mesh <NUM> may be tapered. The tapered proximal portion <NUM> may transition the braided mesh <NUM> from a larger diameter (e.g., greater than or equal to <NUM> millimeters (mm)) near a distal end <NUM> of the proximal portion <NUM> to a smaller diameter near a proximal end <NUM> of the braided mesh <NUM>. In embodiments, the braided mesh <NUM> may be collapsed into a smaller diameter for delivery into the heart <NUM>. Once arranged within the heart <NUM>, the braided mesh <NUM> may be expanded to its larger diameter. By being able to expand to a larger diameter than its delivery configuration, the cannula <NUM> may provide larger flow rates than can be provided with a non-expandable smaller diameter cannula. In embodiments, the braided mesh <NUM> may be designed to adequately withstand the pressure gradient between the inside and the outside of the cannula <NUM>.

In embodiments, the braided mesh <NUM> is coated with a membrane to form a conduit through the cannula <NUM> from the distal portion <NUM> to the proximal portion <NUM>. In embodiments, the membrane may be silicone. In embodiments, the cannula <NUM> is formed from a plurality of nitinol wires having a diameter of <NUM>". However, this is only an example and other types of wires having other diameters may be used to form the cannula <NUM>. Additionally, or alternatively, wires having varying diameters may be used to form the cannula <NUM>. In embodiments, the cannula <NUM> may be formed from a range of nitinol wires (e.g., <NUM> wires to <NUM> wires).

<FIG> depicts a side view of a distal portion <NUM> of the cannula <NUM> depicted in <FIG>, in accordance with embodiments of the subject matter disclosed herein. In embodiments, at the distal end <NUM> of the braided mesh <NUM>, the wires of the cannula <NUM> may include wires <NUM> that extend in a distal direction and be coupled to a tip element <NUM>. The spaces between the wires <NUM> provide an inlet for blood to enter the cannula <NUM>. Additionally, or alternatively, the tip element <NUM> may prevent the suction of tissue into the cannula <NUM>. Additionally, or alternatively, the tip element <NUM> may be radiopaque to help determine proper positioning of the cannula <NUM>. In embodiments, the tip element <NUM> may include an opening at its distal end <NUM> so a guidewire can be passed through the opening to guide the cannula <NUM> to an appropriate location within the heart <NUM>.

<FIG> depicts a side view of a proximal portion <NUM> of the cannula <NUM> and the adaptor <NUM> depicted in <FIG>, in accordance with embodiments of the subject matter disclosed herein. In embodiments, the proximal portion <NUM> of the cannula <NUM> may have an annular cross section and is coupled to the adaptor <NUM>. For example, the braided mesh <NUM> may include a plurality of wire elements <NUM> that are arranged through channels in the adaptor <NUM> to interlock the wires of the cannula <NUM> to the adaptor <NUM>, as described in more detail below. In embodiments, the plurality of wire elements <NUM> may be a plurality of wire loop elements. In embodiments, any of the wire loop elements discussed herein may be replaced with linear elements and/or other wire elements. For example, the wire elements <NUM> may be linear elements that are arranged through the channels of the adaptor <NUM> and secured to the adaptor <NUM> by an interference fit between the adaptor <NUM> and the proximal portion <NUM> of the cannula <NUM>. In embodiments, the elements <NUM> may be welded to the adaptor <NUM> and/or secure to the adaptor in another manner using, for example, an adhesive, etc. The wire elements <NUM> facilitate attaching the braided mesh <NUM> to the adaptor <NUM> while maintaining a small cross-sectional profile for the proximal portion <NUM> of the cannula <NUM>.

In embodiments, the adaptor <NUM> may also be coupled to a ventricular assist device <NUM>, which facilitates the flow of blood through the cannula <NUM>. In embodiments, the adaptor <NUM> be coupled to the ventricular assist device <NUM> by welding, soldering, screw fitting, and/or the like.

<FIG> depicts a perspective view of an exemplary adaptor <NUM> and <FIG> depicts a side view of the exemplary adaptor <NUM> including wire elements coupled thereto, in accordance with embodiments of the subject matter disclosed herein. Similar to the adaptor <NUM>, the adaptor <NUM> may secure a cannula (e.g., the cannula <NUM>) to a circulatory support device (e.g., the circulatory support device <NUM>). As illustrated, the adaptor <NUM> may have a substantially annular cross-sectional profile having an inner diameter through which a circulatory support device may be received. In embodiments, the inner diameter of the adaptor <NUM> may be configured to receive different sized circulatory support devices. For example, the inner diameter of the adaptor <NUM> may range from <NUM>" to <NUM>". In other examples, the inner diameter of the adaptor <NUM> may be less than <NUM>". In even other examples, the inner diameter of the adaptor <NUM> may be larger than <NUM>".

In the illustrated embodiment, the adaptor <NUM> also includes a plurality of channels <NUM> circumferentially arranged around an inner surface <NUM> of the adaptor <NUM>. In embodiments, the channels <NUM> may extend along an entire length <NUM> of the adaptor <NUM>. In embodiments, the channels <NUM> may form posts <NUM> extending from a distal end <NUM> of the adaptor <NUM> to a proximal end <NUM> of the adaptor <NUM>. For example, a single post <NUM> may be formed between two channels <NUM> of the plurality of channels <NUM>. In embodiments, the posts <NUM> may secure the loop elements of a cannula (e.g., the cannula <NUM>) to the adaptor <NUM>. For example, as illustrated in <FIG>, a wire of a cannula may be arranged through a first channel <NUM> of the plurality of channels <NUM> around a proximal end <NUM> of a post <NUM>, and through a second channel <NUM> of the plurality of channels <NUM> to form a wire loop <NUM>. Once the adaptor <NUM> is coupled to a circulatory support device <NUM>, the posts <NUM> may provide an interference fit with the circulatory support device <NUM> and prevent the wire loops <NUM> from pulling out of the adaptor <NUM>.

<FIG> depicts a perspective view of another exemplary adaptor <NUM> and <FIG> depicts a side view of the exemplary adaptor <NUM> including wire elements coupled thereto, in accordance with embodiments of the subject matter disclosed herein. Similar to the adaptor <NUM>, the adaptor <NUM> may secure a cannula (e.g., the cannula <NUM>) to a circulatory support device (e.g., the circulatory support device <NUM>). As illustrated, the adaptor <NUM> may have a substantially annular cross-sectional profile having an inner diameter through which a circulatory support device may be received. In embodiments, the inner diameter of the adaptor <NUM> may be configured to receive different sized circulatory support devices. For example, the inner diameter of the adaptor <NUM> may range from <NUM>" to <NUM>". In other examples, the inner diameter of the adaptor <NUM> may be less than <NUM>". In even other examples, the inner diameter of the adaptor <NUM> may be larger than <NUM>".

In embodiments, the adaptor <NUM> may include a distal cylindrical portion <NUM> and a proximal cylindrical portion <NUM>. In embodiments, the adaptor <NUM> also may include a plurality of elongated members <NUM> that extend between the distal cylindrical portion <NUM> and the proximal cylindrical portion <NUM>. Additionally, or alternatively, conduits <NUM> extending through a thickness of the adaptor <NUM> may separate each of the elongate members <NUM>. In embodiments, the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, and the plurality of elongate members <NUM> may be a monolithic member. Alternatively, the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, and/or the plurality of elongate members <NUM> may be separate members.

In embodiments, the adaptor <NUM> includes a plurality of channels <NUM> circumferentially arranged around an inner surface <NUM> of the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, or both. In the illustrated embodiment, the channels <NUM> may extend along: an entire length <NUM> of the distal cylindrical portion <NUM> and/or an entire length <NUM> of the proximal cylindrical portion <NUM>.

Referring to <FIG>, the channels <NUM> and/or the elongated members <NUM> may prevent the loop elements of a cannula (e.g., the cannula <NUM>) from pulling out of the adaptor <NUM>. For example, a wire of a cannula may be arranged through a first channel <NUM> of the plurality of channels <NUM>, around an elongate member <NUM> and through a second channel <NUM> of the plurality of channels <NUM> to form wire loops <NUM>. The arrangement of the wire loops <NUM> around the elongate members <NUM> may prevent the wire loops <NUM> from pulling out of the adaptor <NUM>.

<FIG> depicts a perspective view of even another exemplary adaptor <NUM> and <FIG> depicts a side view of the exemplary adaptor <NUM> including wire loops, in accordance with embodiments of the subject matter disclosed herein. Similar to the adaptor <NUM>, the adaptor <NUM> may secure a cannula (e.g., the cannula <NUM>) to a circulatory support device (e.g., the circulatory support device <NUM>). As illustrated, the adaptor <NUM> may have a substantially annular cross-sectional profile having an inner diameter through which a circulatory support device may be received. In embodiments, the inner diameter of the adaptor <NUM> may be configured to receive different sized circulatory support devices. For example, the inner diameter of the adaptor <NUM> may range from <NUM>" to <NUM>". In other examples, the inner diameter of the adaptor <NUM> may be less than <NUM>". In even other examples, the inner diameter of the adaptor <NUM> may be larger than <NUM>".

In embodiments, the adaptor <NUM> includes a plurality of channels <NUM> circumferentially arranged around an inner surface <NUM> of the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, or both. In the illustrated embodiment, the channels <NUM> may extend along an entire length <NUM> of the distal cylindrical portion <NUM> and/or only a portion of the length <NUM> of the proximal cylindrical portion <NUM>. By only extending along a portion of the length <NUM> of the proximal cylindrical portion <NUM>, the proximal cylindrical portion <NUM> may have a larger diameter located near a proximal end <NUM> of the adaptor <NUM>. As such, a larger diameter circulatory support device may be received by the adaptor <NUM> in comparison to an embodiment where the channels <NUM> extend along an entire length <NUM> of the proximal cylindrical portion <NUM>. Alternatively, the adaptor <NUM> may have a smaller cross-sectional profile than if the adaptor <NUM> includes channels <NUM> extending along an entire length <NUM> of the proximal cylindrical portion <NUM> when the same size circulatory support device is used in both embodiments.

<FIG> depicts a perspective view of even another exemplary adaptor <NUM>, in accordance with embodiments of the subject matter disclosed herein. Similar to the adaptor <NUM>, the adaptor <NUM> may secure a cannula (e.g., the cannula <NUM>) to a circulatory support device (e.g., the circulatory support device <NUM>). As illustrated, the adaptor <NUM> may have a substantially annular cross-sectional profile having an inner diameter through which a circulatory support device may be received. In embodiments, the inner diameter of the adaptor <NUM> may be configured to receive different sized circulatory support devices. For example, the inner diameter of the adaptor <NUM> may range from <NUM>" to <NUM>". In other examples, the inner diameter of the adaptor <NUM> may be less than <NUM>". In even other examples, the inner diameter of the adaptor <NUM> may be larger than <NUM>".

In embodiments, the adaptor <NUM> may include a distal cylindrical portion <NUM> and a proximal cylindrical portion <NUM>. In embodiments, the adaptor <NUM> also may include one or more intermediate cylindrical portions <NUM> that extend between the distal cylindrical portion <NUM> and the proximal cylindrical portion <NUM>. In embodiments, the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, and the one or more intermediate cylindrical portions <NUM> may be a monolithic member. Alternatively, the distal cylindrical portion <NUM>, the proximal cylindrical portion <NUM>, and/or the one or more intermediate cylindrical portions <NUM> may be separate members.

In embodiments, the adaptor <NUM> includes a plurality of channels <NUM> circumferentially arranged around the distal cylindrical portion <NUM>. In the illustrated embodiment, the channels <NUM> may extend along an entire length <NUM> of the distal cylindrical portion <NUM>. In embodiments, a wire of a cannula may be arranged through a first channel <NUM> of the plurality of channels <NUM>, around a proximal end <NUM> of the distal cylindrical portion <NUM> and through a second channel <NUM> of the plurality of channels <NUM> to form wire loops that are prevented from pulling out of the adaptor <NUM>.

In embodiments, the adaptor <NUM> includes a plurality of channels <NUM> circumferentially arranged around the distal cylindrical portion <NUM>. In the illustrated embodiment, the channels <NUM> may extend along an entire length <NUM> of the distal cylindrical portion <NUM>. In embodiments, a wire of a cannula may be arranged through a first channel <NUM> of the plurality of channels <NUM>, around a proximal end <NUM> of the distal cylindrical portion <NUM> and through a second channel <NUM> of the plurality of channels <NUM> to form wire loops <NUM> that are prevented from pulling out of the adaptor <NUM>. In embodiments, the wire loops <NUM> may lay in troughs (beneath the wire loops <NUM>) to prevent lateral movement of the wire loops <NUM>.

<FIG> depicts is a side view of an exemplary mandrel <NUM> used to form an exemplary cannula, in accordance with embodiments of the subject matter disclosed herein. As illustrated, the mandrel <NUM> comprises a proximal portion <NUM> including an adaptor <NUM> coupled thereto, an intermediate portion <NUM>, and a distal portion <NUM>. Proximal portions of wires <NUM> (shown in <FIG>) may be arranged through channels in the adaptor <NUM> to keep the wires <NUM> stationary while the braiding of the wires <NUM> is performed. In embodiments, the mandrel <NUM> also includes a plurality of protrusions <NUM>. As illustrated in <FIG>, which depicts a side view of a distal portion of the exemplary mandrel depicted <NUM> in <FIG>, wires <NUM> may be wrapped and/or braided around the plurality of protrusions <NUM> to form the braided mesh (e.g., the braided mesh <NUM>) of the cannula (e.g., the cannula <NUM>). In embodiments, the intermediate portion <NUM> may include protrusions <NUM> having a constant pitch or a varying pitch.

<FIG> illustrates an exemplary mandrel <NUM> including protrusions <NUM> having a constant pitch and <FIG> illustrates an exemplary mandrel <NUM> including protrusions <NUM> having a varying pitch. In embodiments, a pitch angle is the angle formed by two proximal edges of a protrusion and/or two distal edges of a protrusion. For example, referring to <FIG>, two different pitch angles are illustrated. In <FIG>, the protrusion <NUM> has edges <NUM> that form a pitch angle of <NUM> degrees. In comparison, the protrusion <NUM> has edges <NUM> that form a pitch angle of <NUM> degrees. However, these are only examples and not meant to be limiting and the pitch angle may range from approximately <NUM> degrees to <NUM> degrees.

In embodiments, the pitch angle may determine the dimetric and/or the axial strength of the cannula (e.g., the cannula <NUM>). For example, a greater pitch angle may facilitate a greater dimetric strength while also facilitating a lower axial strength. In comparison, the smaller pitch angle may facilitate a lower dimetric strength while also facilitating a greater axial strength. In embodiments, the dimetric strength and/or the axial strength may be configured for the specific application of cannula and/or selected to withstand the pressure gradient between the inside and the outside of the cannula.

Referring back to <FIG>, the intermediate portion <NUM> may include a tapered portion <NUM> which can be used to form a tapered proximal portion (e.g., the tapered proximal portion <NUM>) of a cannula.

In embodiments, once the wires <NUM> are braided through the protrusions <NUM> to a distal end <NUM> of the protrusions <NUM>, every other wire <NUM> may be looped back and arranged back through the protrusions <NUM>. The wires <NUM> that are not looped back may be arranged through conduits <NUM> of the distal portion <NUM>. In embodiments, once the shape of the wires <NUM> is formed, the looped back portions of the wires <NUM> or the entirety of the wires <NUM> may be welded, affixed, stabilized, and/or heat threated to set the shape of the wires <NUM>. The cannula may then be removed from the mandrel <NUM>. After removing the cannula from the mandrel <NUM>, the cannula may be coated in a membrane.

<FIG> depicts a side view of an exemplary cannula <NUM> that was removed from a mandrel (e.g., the mandrel <NUM>) and has a membrane coating <NUM>, in accordance with embodiments of the subject matter disclosed herein. In embodiments, the membrane may be silicone. As illustrated, the proximal portion <NUM> includes a plurality of proximal wire portions <NUM> extending in a proximal direction. In at least some embodiments, the proximal wire portions <NUM> may extend longitudinally. These wires <NUM> may be looped through an adaptor (e.g., any one of the adaptors <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> discussed above) and then secured to a circulatory support device, as described above. In embodiments, the distal portion <NUM> includes a plurality of distal wire portions <NUM> extending in a distal direction. In at least some embodiments, the distal wire portions <NUM> extend longitudinally. These wires <NUM> may be coupled to a tip element (e.g., the tip element <NUM> discussed above), as discussed above.

Claim 1:
An apparatus for attachment to a cardiac pump, the apparatus comprising:
an adaptor (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) comprising:
an annular cross section configured to receive the cardiac pump, wherein the annular cross section is secured to the cardiac pump; and
a plurality of channels (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>) arranged around the adaptor (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>);
a cannula (<NUM>; <NUM>) comprising a proximal portion (<NUM>), a distal portion (<NUM>; <NUM>) , and an intermediate portion (<NUM>) comprising a braided mesh (<NUM>) extending between the distal portion (<NUM>) and the proximal portion (<NUM>), the proximal portion (<NUM>) having a proximal end (<NUM>) comprising a plurality of elements (<NUM>) arranged through the channels (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and the distal portion (<NUM>) comprising a plurality of wires (<NUM>) and a tip element (<NUM>), wherein the plurality of wires (<NUM>) extend in a distal direction from the braided mesh (<NUM>) to the tip element (<NUM>), wherein the plurality of wires (<NUM>) are secured to the tip element (<NUM>); and
a coating (<NUM>) covering at least a portion of the braided mesh.