Positive Displacement Shuttle Pump Heart and VAD

Abstract

Described herein are devices and methods for pumping blood to patients in need of circulatory assistance or a replacement heart. Instead of providing a temporary solution for these patients, the device can be permanently implanted. The device linearly reciprocates a shuttle within a housing to move blood into and out of the housing, and rotates the shuttle to selectively direct the movement of blood into and out of multiple ports within the housing.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 816,056, filed March 8, 2019, which is incorporated by reference in its entirety.

[0002] This application relates generally to pump devices and methods for maintaining and sustaining the life of patients with weakened, failing or failing hearts, and specifically to artificial devices generally known in the art as "artificial hearts" and "ventricular assist devices" (VADs). [Background technology]

[0003] For many years, practitioners in medical procedures and medical device technology have sought to provide artificial heart devices constructed to supplement or completely replace a failing, failing, or failing heart in a patient-recipient. The most basic long-term need is the creation of a replacement pumping device that can be implanted within a patient's body to completely replace the natural heart and perform the basic blood pumping and circulatory functions of the natural heart. Often, there is an additional need for supplemental devices that are intended to assist a failing or failing heart on a shorter-term basis, but are not usually intended to completely replace the natural heart. Such "supplemental" devices are referred to as "ventricular assist devices" (VADs), such as "left ventricular assist devices" (LVADs) and "right ventricular assist devices" (RVADs).

[0004] Early attempts to provide sustainable heart replacement were severely limited by available technology and the state of the art at the time. Available devices generally proved too large and cumbersome, and in most cases impractical. With continued advances in related and creative technologies, heart replacement devices have become smaller, more reliable, and in some cases, at least partially implantable within the recipient. Such "implantable" devices generally remain hybrid devices, in that the actual pump may be implanted within the recipient, while additional support equipment remains external to the patient and connected to the implanted device by multiple connecting wires and hoses. Despite advances, a fully implantable and practical artificial heart remains elusive and largely unavailable.

[0005] The requirements for an artificial heart or ventricular assist device remain challenging. A successful artificial heart or implantable ventricular assist device must, among other things, be long-lasting and reliable. The dire consequences to device recipients caused by device failure make this requirement very evident. Given that currently available devices pump blood using rotating components that must rotate at high speeds to achieve adequate blood flow and blood pressure, they provide a temporary solution to heart failure and act as a bridge to heart transplantation.

[0006] In addition, the device must be small enough to be implantable within the recipient's chest and efficient enough to maintain adequate blood circulation to sustain normal life functions. The device must avoid undue stress on the recipient's circulatory and pulmonary systems. The device must also be able to adapt and adjust to various recipient activity levels and stresses. Additional requirements such as avoiding turbulence in the bloodstream, as well as avoiding blood cell damage from the pumping device and preventing thrombus formation stagnation areas, place further demands on artificial hearts and ventricular assist devices.

[0007] Thus, while practitioners of medical procedures and medical device technology have created a virtually endless variety of proposed artificial heart and ventricular assist devices, there nevertheless remains a continuing unmet need in the art for improved, implantable, reliable and effective artificial heart and ventricular assist devices that meet the stringent and unrelenting key requirements and challenges posed by a truly fully functional, fully implantable artificial heart or ventricular assist device.

[0008] Therefore, it would be useful to have improved ventricular assist devices and artificial heart devices. Summary of the Invention [Means for solving the problem]

[0009] Described herein are devices and methods for pumping blood to patients who require circulatory assistance or replacement hearts. Instead of providing a temporary solution for these patients (recipients), the devices can be permanently implanted. Device features that may allow for permanent implantation include, but are not limited to, the lack of an impeller that must rotate at high speeds to effectively pump blood, and the shuttle that uses primarily linear motion to generate blood flow, and materials used to make the components, allowing them to be precisely machined. The tight tolerances achieved by precision machining prevent red blood cells from migrating between device components and being damaged, as well as minimizing the number of components in the device, since there is no need to include at least seals. In addition to providing a slower pump speed that corresponds more closely to heart rates in the normal range for the recipient, the linear motion of the shuttle further prevents damage to red blood cells, since it does not generate shear forces.

[0010] As used herein, the terms "cylinder," "housing," and "cylindrical housing" are used interchangeably throughout, and the terms "cylinder bore," "cylinder head," and "chamber" are used interchangeably throughout. However, it should be understood that the housing can be, but need not be, cylindrical. Additionally, use of the term "about" generally means within ±5% of a value or measurement.

[0011] An embodiment is disclosed herein that provides a reliable and effective implantable ventricular assist device utilizing a single-acting positive displacement shuttle pump. Further embodiments are also disclosed herein that provide a reliable and effective implantable ventricular assist device utilizing a double-acting positive displacement shuttle pump. Yet another embodiment is disclosed herein that provides a reliable and effective implantable artificial heart utilizing a double-acting positive displacement shuttle pump.

[0012] The device for pumping blood described herein generally comprises a cylindrical housing with an outer surface, a plurality of ports, a first end, and a second end, the first and second ends defining a chamber therebetween. A shuttle is contained within the chamber, the shuttle comprising an outer sleeve defining a hollow interior surface and one or more channels extending longitudinally along the outer sleeve. The chamber may be a fixed volume chamber such that the shuttle moving within the chamber defines two separate variable volume portions. The device may also include a magnetic actuation system operable to impart linear and rotational motion to the shuttle, the linear motion of the shuttle pumping blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directing the flow of blood through the plurality of ports. A biocompatible coating may also be provided on the housing outer surface. The device may be a ventricular assist device or an artificial heart.

[0013] The housing, the shuttle, or both may be made from or may include a ceramic material. Exemplary ceramic materials may include sapphire, synthetic variants of sapphire, zirconia, or synthetic variants of zirconia.

[0014] A manifold that helps direct the flow of blood may be associated with the cylindrical housing. The manifold may be integrally formed with the housing or coupled thereto. For example, the manifold may be coupled to the housing using an attachment mechanism such as a strap or strip of material. The strap or strip may be secured around the housing by a latch or other suitable fastening component.

[0015] When included as part of an artificial heart device, the manifold may include first and second inlets and first and second outlets, the first and second inlets and first and second outlets being in fluid communication with ports corresponding to the plurality of ports. The first and second inlets of the manifold may be spaced apart about 90 degrees on an exterior surface of the cylindrical housing. Similarly, the first and second outlets of the manifold may be spaced apart about 90 degrees on an exterior surface of the cylindrical housing.

[0016] In the case of a ventricular assist device, the manifold may include a single inlet and a single outlet, both of which may be in fluid communication with a port corresponding to the multiple ports, where the inlets and outlets of the manifold may be spaced approximately 90 degrees apart on the exterior surface of the cylindrical housing.

[0017] The housing and shuttle components of the device typically have a minimal clearance gap between them. For example, the clearance gap may be less than about 5.0 μm, less than about 4.0 μm, or less than about 3.0 μm. In some cases, the clearance gap may be about 2.0 μm to about 4.0 μm. The clearance gap may generally be sized to prevent passage of red blood cells between the housing and shuttle, thereby eliminating the need to include a seal within the device.

[0018] The shuttle of the device disclosed herein may include a hollow cylindrical sleeve and an end cap at each end of the sleeve. The shuttle may have a length and a diameter, and one or more channels extending along the outer surface of the sleeve. The shuttle diameter may be about 3.5 cm to about 4.5 cm. The shuttle length may be about 5.0 cm to about 6.0 cm.

[0019] Additionally, the one or more channels may have one open end and one closed end. The length of the channel may be from about 4.0 cm to about 5 cm. The depth of the one or more channels may be from about 0.5 cm to about 0.6 cm. In general, the channels may be formed without square edges and may include only rounded edges.

[0020] Movement of the shuttle within the housing may generally be accomplished using a magnetic actuation system. The magnetic actuation system may include a plurality of magnets disposed within the hollow interior surface of the outer sleeve, a plurality of linear motor coils surrounding the cylindrical housing, and a plurality of rotating coils disposed at the first and second ends of the cylindrical housing. Alternatively, the magnetic actuation system may include a plurality of magnets disposed within the hollow interior surface of the outer sleeve, a plurality of linear motor coils surrounding the cylindrical housing, and a permanent magnet disposed within each of the first and second ends of the cylindrical housing.

[0021] The controller may be operatively coupled to the magnetic actuation system and configured to automatically control the pumping cycle using a feedback loop. Here, one or more pressure sensors may be operatively connected to the controller. Blood pressure data received by the controller from the one or more pressure sensors may be used to automatically adjust the magnetic actuation system to increase or decrease the rate or speed of the pumping cycle. Manual adjustments of the pumping cycle may also be made by the device recipient or a physician. In some cases, the controller may include a Bluetooth system operable to transmit information about the pump device to an external device, such as a computer, a cell phone, or a handheld mobile controller. In other examples, the controller may include a telemetry system operable to transmit information about the device to and receive information from an external device. One or more rechargeable batteries may be included with the pump device. The batteries may be implanted in any suitable location in the recipient's body. For example, a first battery may be implanted just above or approximately the area of ​​the recipient's left hip, and a second battery may be implanted just above or approximately the area of ​​the recipient's right hip.

[0022] Some devices for pumping blood described herein may include a cylindrical housing with an outer surface, first and second inlet ports, first and second outlet ports, a first end, and a second end, the first and second ends defining a chamber therebetween, a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow inner surface containing a plurality of magnets therein, and one or more channels extending longitudinally along the outer sleeve, and a magnetic actuation system operable to impart linear and rotational motion to the shuttle, the linear motion of the shuttle pumping blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directing the flow of blood through the first and second inlet ports and the first and second outlet ports. Here, the device may be an artificial heart. The device may further include a manifold associated with the cylindrical housing, the manifold including first and second inlets and first and second outlets, the first and second inlets and first and second outlets in fluid communication with ports corresponding to the first and second inlet ports and the first and second outlet ports.

[0023] Another exemplary artificial heart described herein may include a cylindrical housing with multiple ports, a shuttle within the cylindrical housing, the shuttle being made from a sapphire material, and a clearance gap between the housing and the shuttle, the clearance gap being sized to prevent passage of red blood cells. The clearance gap may be about 2.0 μm to about 4.0 μm.

[0024] Further, some devices for pumping blood described herein may include a cylindrical housing with an outer surface, a single inlet port, a single outlet port, a first end, and a second end, the first and second ends defining a chamber therebetween, a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow inner surface containing a plurality of magnets, and one or more channels extending longitudinally along the outer sleeve, and a magnetic actuation system operable to impart linear and rotational motion to the shuttle, the linear motion of the shuttle pumping blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directing the flow of blood through the single inlet port and the single outlet port. Here, the device may be a ventricular assist device. The device may further include a manifold including a single inlet and a single outlet, both of which are in fluid communication with a corresponding single inlet port and a corresponding single outlet port.

[0025] Methods for pumping blood into a recipient are further described herein. The methods may generally include linearly reciprocating a shuttle contained within a housing to simultaneously move blood into and out of the housing according to a pumping cycle, the housing comprising a plurality of ports, and rotating the shuttle to selectively direct the movement of blood into and out of the plurality of ports. In some cases, the methods also include implanting the housing into the recipient. The implanting may include coupling a first port of the plurality of ports to the recipient's aorta and coupling a second port of the plurality of ports to the recipient's left ventricle. Alternatively, the implanting may include coupling a first port of the plurality of ports to the recipient's aorta, coupling a second port of the plurality of ports to the recipient's pulmonary artery, coupling a third port of the plurality of ports to the recipient's inferior and superior vena cava, and coupling a fourth port of the plurality of ports to the recipient's pulmonary vein. The pumping cycle of the device may be adjusted automatically based on the recipient's blood pressure, or may be adjusted manually by the recipient or a physician.

[0026] Some of the methods described herein may include implanting a housing having a plurality of ports in a recipient, including connecting a first port of the plurality of ports to the recipient's aorta, connecting a second port of the plurality of ports to the recipient's pulmonary artery, connecting a third port of the plurality of ports to the recipient's inferior vena cava and superior vena cava, and connecting a fourth port of the plurality of ports to the recipient's pulmonary vein, linearly reciprocating a shuttle contained within the housing to simultaneously move blood into and out of the housing according to a pumping cycle, and rotating the shuttle to selectively direct the movement of blood into and out of the plurality of ports.

[0027] Other methods described herein may include implanting a housing having a plurality of ports in a recipient, including connecting a first port of the plurality of ports to the aorta of the recipient and connecting a second port of the plurality of ports to the left ventricle of the recipient, linearly reciprocating a shuttle contained within the housing to simultaneously move blood into and out of the housing according to a pumping cycle, and rotating the shuttle to selectively direct movement of blood into and out of the plurality of ports.

[0028] Methods for treating heart failure are further described herein. The methods may generally include implanting a housing with a shuttle into a recipient, linearly reciprocating the shuttle to simultaneously move blood into and out of the housing, and rotating the shuttle to direct the flow of blood into and out of the housing, where the linearly reciprocating and rotating the shuttle creates a pumping cycle of the housing. Again, the housing and shuttle may function as a ventricular assist device or as an artificial heart. Types of heart failure that may be treated include, but are not limited to, left-sided heart failure, right-sided heart failure, biventricular heart failure, cardiomyopathy, or heart failure due to infection.

[0029] More specifically, various embodiments disclosed herein may utilize a cylinder having closed opposing ends and a cylinder bore extending therebetween. Within the cylinder bore, a shuttle, generally cylindrical and supporting a plurality of magnets, may be freely movable. Input and output ports may be formed within the cylinder at a midpoint of the cylindrical bore to provide connection to a recipient's circulatory system, if necessary for a ventricular assist device or artificial heart procedure. A set of linear motor coils may be disposed on an outer surface of the cylinder and configured to interact with magnets supported within the shuttle. An electrical signal may be applied to the linear motor coils by a controller to drive the shuttle in a reciprocating motion between the closed ends of the cylinder. The outer surface of the shuttle may define one or more blood flow channels, each of which may be open at one end and closed at the other end. Additionally, a magnetic component may be provided to rotate the shuttle before each reciprocating motion to align a selected blood flow channel with a selected input and output port. By proper rotational positioning of the shuttle and its linear motion once rotationally positioned, blood can be drawn into one end of the cylindrical housing, and then rotation of the shuttle can align a selected blood flow channel such that returning linear motion of the shuttle can displace blood accumulated there outwardly through the output port.

[0030] In single-acting embodiments of the pump device, blood may be drawn into and pumped from one end of the cylindrical housing as the shuttle reciprocates. In double-acting embodiments of the pump device, blood may be simultaneously drawn into the cylinder at one end and expelled from the cylinder at the other end as the shuttle reciprocates. For both single-acting and double-acting embodiments of the pump device, the reciprocating and rotational motion of the shuttle may be sequenced to draw successive amounts of blood into the cylinder through the input port and displace it outwardly from the cylinder through the output port. The present invention provides, for example, the following items. (Item 1) 1. A device for pumping blood, comprising: a cylindrical housing having an exterior surface, a plurality of ports, a first end, and a second end, the first and second ends defining a chamber therebetween; a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow interior surface containing a plurality of magnets and one or more channels extending longitudinally along the outer sleeve; a magnetic actuation system operable to impart linear and rotational motion to the shuttle; The device, wherein the linear motion of the shuttle pumps blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directs blood flow through the plurality of ports. (Item 2) 2. The device of claim 1, wherein the housing, the shuttle, or both, comprise a ceramic material. (Item 3) 3. The device of claim 2, wherein the ceramic material comprises sapphire or a synthetic variant thereof. (Item 4) 3. The device of claim 2, wherein the ceramic material comprises zirconia or a synthetic variant thereof. (Item 5) Item 1 , the device wherein the cylindrical housing is associated with a manifold. (Item 6) 6. The device of claim 5, wherein the manifold includes first and second inlets and first and second outlets, the first and second inlets and the first and second outlets being in fluid communication with ports corresponding to the plurality of ports. (Item 7) 7. The device of claim 6, wherein the first and second inlets of the manifold are spaced approximately 90 degrees apart on the outer surface of the cylindrical housing. (Item 8) 7. The device of claim 6, wherein the first and second outlets of the manifold are spaced approximately 90 degrees apart on the outer surface of the cylindrical housing. (Item 9) Item 6. The device of item 5, wherein the manifold includes a single inlet and a single outlet, both of which are in fluid communication with ports corresponding to the plurality of ports. (Item 10) 10. The device of claim 9, wherein the manifold inlet and the outlet are spaced approximately 90 degrees apart on the exterior surface of the cylindrical housing. (Item 11) 2. The device of claim 1, wherein the device includes a clearance gap between the housing and the shuttle. (Item 12) Item 12. The device of item 11, wherein the clearance gap is less than about 5.0 μm. (Item 13) Item 13. The device of item 12, wherein the clearance gap is less than about 4.0 μm. (Item 14) Item 14. The device of item 13, wherein the clearance gap is less than about 3.0 μm. (Item 15) Item 12. The device of item 11, wherein the clearance gap is about 2.0 to 4.0 μm. (Item 16) Item 12. The device of item 11, wherein the clearance gap is sized to prevent passage of red blood cells between the housing and the shuttle. (Item 17) Item 2. The device of item 1, wherein the shuttle has a diameter of about 3.5 cm to about 4.5 cm. (Item 18) 2. The device of claim 1, wherein the shuttle has a length of about 5.0 cm to about 6.0 cm. (Item 19) 2. The device of claim 1, wherein the one or more channels have one open end and one closed end. (Item 20) 2. The device of item 1, wherein the one or more channels have a length of about 4.0 cm to about 5 cm. (Item 21) Item 2. The device of item 1, wherein the one or more channels have a depth of about 0.5 cm to about 0.6 cm. (Item 22) Item 1 . The device of item 1 , wherein the one or more channels include only rounded edges. (Item 23) 2. The device of claim 1, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a plurality of rotating coils disposed at the first and second ends of the cylindrical housing. (Item 24) 2. The device of claim 1, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a permanent magnet disposed within each of the first and second ends of the cylindrical housing. (Item 25) 2. The device of claim 1, wherein the device comprises a controller operably coupled to the magnetic actuation system and configured to control the pumping cycle. (Item 26) Item 26. The device of item 25, wherein the controller is operably connected to a pressure sensor. (Item 27) Item 26. The device of item 25, wherein the controller comprises a Bluetooth system operable to transmit information about the device to an external device. (Item 28) 26. The device of claim 25, wherein the controller comprises a telemetry system operable to transmit information about the device to an external device and receive information from the external device. (Item 29) Item 1. The device of item 1, further comprising a coating on an exterior surface of the housing. (Item 30) Item 1. The device of item 1, further comprising at least one rechargeable battery. (Item 31) 2. The device of item 1, wherein the device is an artificial heart. (Item 32) 2. The device of item 1, wherein the device is a ventricular assist device. (Item 33) 1. A method of pumping blood into a recipient, comprising: linearly reciprocating a shuttle contained within a housing to simultaneously move blood into and out of said housing according to a pumping cycle, said housing comprising a plurality of ports; and rotating the shuttle to selectively direct movement of blood into and out of the plurality of ports. (Item 34) 34. The method of claim 33, further comprising implanting the housing within the recipient. (Item 35) 35. The method of claim 34, wherein implanting comprises connecting a first port of the plurality of ports to an aorta of the recipient and connecting a second port of the plurality of ports to a left ventricle of the recipient. (Item 36) 35. The method of claim 34, wherein implanting comprises connecting a first port of the plurality of ports to the aorta of the recipient, connecting a second port of the plurality of ports to the pulmonary artery of the recipient, connecting a third port of the plurality of ports to the inferior vena cava and superior vena cava of the recipient, and connecting a fourth port of the plurality of ports to a pulmonary vein of the recipient. (Item 37) 34. The method of claim 33, wherein the rate of the pumping cycle is automatically adjusted based on the recipient's blood pressure. (Item 38) 34. The method of claim 33, wherein the rate of the pumping cycle is manually adjusted by the recipient. (Item 39) 34. The method of claim 33, wherein the rate of the pumping cycle is manually adjusted by a physician. (Item 40) 34. The method of claim 33, wherein the housing is a ventricular assist device. (Item 41) 34. The method of claim 33, wherein the housing is an artificial heart. (Item 42) 1. A method for treating heart failure, comprising: Implanting a housing comprising the shuttle into a recipient; linearly reciprocating the shuttle to simultaneously move blood into and out of the housing; rotating the shuttle to selectively direct blood flow into and out of the housing; A method wherein linearly reciprocating and rotating the shuttle creates a pumping cycle. (Item 43) 43. The method of claim 42, wherein the housing is a ventricular assist device. (Item 44) Item 43. The method of item 42, wherein the housing is an artificial heart. (Item 45) 43. The method of claim 42, wherein the rate of the pumping cycle is automatically adjusted based on the recipient's blood pressure. (Item 46) 43. The method of claim 42, wherein the rate of the pumping cycle is manually adjusted by the recipient. (Item 47) 43. The method of claim 42, wherein the rate of the pumping cycle is manually adjusted by a physician. (Item 48) 43. The method of claim 42, wherein the heart failure is due to left-sided heart failure, right-sided heart failure, biventricular heart failure, cardiomyopathy, or infection. (Item 49) An artificial heart, a cylindrical housing having an exterior surface, first and second inlet ports, first and second outlet ports, a first end, and a second end, the first and second ends defining a chamber therebetween; a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow interior surface containing a plurality of magnets therein and one or more channels extending longitudinally along the outer sleeve; a magnetic actuation system operable to impart linear and rotational motion to the shuttle; the linear motion of the shuttle pumps blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directs blood flow through the first and second inlet ports and the first and second outlet ports. (Item 50) 50. The heart artificial according to item 49, wherein the heart artificial comprises a manifold including a first inlet, a second inlet, a first outlet, and a second outlet, the first and second inlets and the first and second outlets being in fluid communication with ports corresponding to the first and second inlet ports and the first and second outlet ports. (Item 51) 50. The artificial heart of claim 49, wherein the housing, the shuttle, or both, comprise a ceramic material. (Item 52) 52. The artificial heart according to item 51, wherein the ceramic material comprises sapphire or a synthetic variant thereof. (Item 53) 52. The artificial heart according to item 51, wherein the ceramic material comprises zirconia or a synthetic variant thereof. (Item 54) 50. The heart prosthesis of claim 49, wherein the first and second inlets of the manifold are spaced approximately 90 degrees apart on the outer surface of the cylindrical housing. (Item 55) 50. The heart prosthesis of claim 49, wherein the first and second outlets of the manifold are spaced approximately 90 degrees apart on the outer surface of the cylindrical housing. (Item 56) 50. The artificial heart of claim 49, wherein the device includes a clearance gap between the housing and the shuttle. (Item 57) 57. The artificial heart according to item 56, wherein the clearance gap is less than about 5.0 μm. (Item 58) 58. The artificial heart according to item 57, wherein the clearance gap is less than about 4.0 μm. (Item 59) Item 59. The artificial heart according to item 58, wherein the clearance gap is less than about 3.0 μm. (Item 60) Item 57. The artificial heart according to item 56, wherein the clearance gap is about 2.0 to 4.0 μm. (Item 61) Item 57. The heart prosthesis of item 56, wherein the clearance gap is sized to prevent passage of red blood cells between the housing and the shuttle. (Item 62) Item 50. The artificial heart according to item 49, wherein the shuttle has a diameter of about 3.5 cm to about 4.5 cm. (Item 63) Item 50. The artificial heart according to item 49, wherein the shuttle has a length of about 5.0 cm to about 6.0 cm. (Item 64) 50. The heart prosthesis of claim 49, wherein the one or more channels have one open end and one closed end. (Item 65) Item 50. The artificial heart according to item 49, wherein the one or more channels have a length of about 4.0 cm to about 5 cm. (Item 66) Item 50. The artificial heart according to item 49, wherein the one or more channels have a depth of about 0.5 cm to about 0.6 cm. (Item 67) 50. The heart prosthesis of claim 49, wherein the one or more channels include only rounded edges. (Item 68) 50. The heart prosthesis of claim 49, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a plurality of rotating coils disposed at the first and second ends of the cylindrical housing. (Item 69) 50. The artificial heart of claim 49, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a permanent magnet disposed within each of the first and second ends of the cylindrical housing. (Item 70) 50. The artificial heart of claim 49, wherein the device includes a controller operably coupled to the magnetic actuation system and configured to control the pumping cycle. (Item 71) Item 71. The artificial heart of item 70, wherein the controller is operably connected to a pressure sensor. (Item 72) 71. The artificial heart of item 70, wherein the controller comprises a Bluetooth® system operable to transmit information about the device to an external device. (Item 73) 71. The heart prosthesis of claim 70, wherein the controller comprises a telemetry system operable to transmit information about the device to an external device and receive information from the external device. (Item 74) 50. The artificial heart of claim 49, further comprising a coating on an exterior surface of the housing. (Item 75) 50. The artificial heart according to item 49, further comprising at least one rechargeable battery. (Item 76) 1. A method of pumping blood into a recipient, comprising: implanting in the recipient a housing comprising a plurality of ports, the housing comprising: connecting a first port of the plurality of ports to the aorta of the recipient; connecting a second port of the plurality of ports to the pulmonary artery of the recipient; connecting a third port of the plurality of ports to the inferior and superior vena cava of the recipient; and connecting a fourth port of the plurality of ports to a pulmonary vein of the recipient; linearly reciprocating a shuttle contained within the housing to simultaneously move blood into and out of the housing according to a pumping cycle; and rotating the shuttle to selectively direct movement of blood into and out of the plurality of ports. (Item 77) 77. The method of claim 76, wherein the rate of the pumping cycle is automatically adjusted based on the recipient's blood pressure. (Item 78) 80. The method of claim 76, wherein the rate of the pumping cycle is manually adjusted by the recipient. (Item 79) 77. The method of claim 76, wherein the rate of the pumping cycle is manually adjusted by a physician. (Item 80) 1. A ventricular assist device for pumping blood, comprising: a cylindrical housing having an exterior surface, a single inlet port, a single outlet port, a first end, and a second end, said first and second ends defining a chamber therebetween; a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow interior surface containing a plurality of magnets and one or more channels extending longitudinally along the outer sleeve; a magnetic actuation system operable to impart linear and rotational motion to the shuttle; A ventricular assist device, wherein the linear motion of the shuttle pumps blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directs blood flow through the single inlet port and the single outlet port. (Item 81) Item 81. The ventricular assist device of item 80, wherein the ventricular assist device comprises a manifold including a single inlet and a single outlet, the single inlet being in fluid communication with the single inlet port of the cylindrical housing and the single outlet being in fluid communication with the single outlet port of the cylindrical housing. (Item 82) 81. The ventricular assist device of claim 80, wherein the housing, the shuttle, or both, comprise a ceramic material. (Item 83) 83. The ventricular assist device of claim 82, wherein the ceramic material comprises sapphire or a synthetic variant thereof. (Item 84) 83. The ventricular assist device of claim 82, wherein the ceramic material comprises zirconia or a synthetic variant thereof. (Item 85) Item 82. The ventricular assist device of item 81, wherein the manifold inlet and outlet are spaced approximately 90 degrees apart on the outer surface of the cylindrical housing. (Item 86) 81. The ventricular assist device of claim 80, wherein the device includes a clearance gap between the housing and the shuttle. (Item 87) Item 87. The ventricular assist device of item 86, wherein the clearance gap is less than about 5.0 μm. (Item 88) Item 88. The ventricular assist device of item 87, wherein the clearance gap is less than about 4.0 μm. (Item 89) Item 89. The ventricular assist device of item 88, wherein the clearance gap is less than about 3.0 μm. (Item 90) Item 87. The ventricular assist device of item 86, wherein the clearance gap is about 2.0 to 4.0 μm. (Item 91) Item 87. The ventricular assist device of item 86, wherein the clearance gap is sized to prevent passage of red blood cells between the housing and the shuttle. (Item 92) Item 81. The ventricular assist device of item 80, wherein the shuttle has a diameter of about 3.5 cm to about 4.5 cm. (Item 93) Item 81. The ventricular assist device of item 80, wherein the shuttle has a length of about 5.0 cm to about 6.0 cm. (Item 94) Item 81. The ventricular assist device of item 80, wherein the one or more channels have one open end and one closed end. (Item 95) Item 81. The ventricular assist device of item 80, wherein the one or more channels have a length of about 4.0 cm to about 5 cm. (Item 96) Item 81. The ventricular assist device of item 80, wherein the one or more channels have a depth of about 0.5 cm to about 0.6 cm. (Item 97) Item 81. The ventricular assist device of item 80, wherein the one or more channels include only rounded edges. (Item 98) Item 81. The ventricular assist device of item 80, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a plurality of rotating coils disposed at the first and second ends of the cylindrical housing. (Item 99) Item 81. The ventricular assist device of item 80, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a permanent magnet disposed within each of the first and second ends of the cylindrical housing. (Item 100) 81. The ventricular assist device of claim 80, wherein the device includes a controller operatively coupled to the magnetic actuation system and configured to control the pumping cycle. (Item 101) Item 101. The ventricular assist device of item 100, wherein the controller is operably connected to a pressure sensor. (Item 102) Item 101. The ventricular assist device of item 100, wherein the controller comprises a Bluetooth® system operable to transmit information about the device to an external device. (Item 103) Item 101. The ventricular assist device of item 100, wherein the controller comprises a telemetry system operable to transmit information about the device to an external device and receive information from the external device. (Item 104) Item 81. The ventricular assist device of item 80, further comprising a coating on an exterior surface of the housing. (Item 105) 81. The ventricular assist device of claim 80, further comprising at least one rechargeable battery. (Item 106) 1. A method of pumping blood into a recipient, comprising: implanting in the recipient a housing comprising a plurality of ports, the housing comprising: coupling a first port of the plurality of ports to an aorta of the recipient; and coupling a second port of the plurality of ports to a left ventricle of the recipient; linearly reciprocating a shuttle contained within the housing to simultaneously move blood into and out of the housing according to a pumping cycle; and rotating the shuttle to selectively direct movement of blood into and out of the plurality of ports. (Item 107) 107. The method of claim 106, wherein the speed of the pumping cycle is automatically adjusted based on the blood pressure of the recipient. (Item 108) 107. The method of claim 106, wherein the rate of the pumping cycle is manually adjusted by the recipient. (Item 109) Item 107. The method of item 106, wherein the rate of the pumping cycle is manually adjusted by a physician. (Item 110) An artificial heart, a cylindrical housing having a plurality of ports; a shuttle within the cylindrical housing, the shuttle being made from a sapphire material; a clearance gap between the housing and the shuttle; The clearance gap is sized to prevent the passage of red blood cells. (Item 111) Item 111. The artificial heart according to item 110, wherein the clearance gap is about 2.0 to 4.0 μm. (Item 112) Item 111. The heart prosthesis of item 110, wherein the housing is associated with a manifold having a pair of inlets and a pair of outlets in fluid communication with ports corresponding to the plurality of ports. (Item 113) Item 111. The heart prosthesis of item 110, wherein the shuttle comprises a pair of channels extending longitudinally along its outer surface. (Item 114) Item 114. The heart prosthesis of item 113, wherein the pair of channels are spaced approximately 180 degrees apart on the outer surface of the shuttle. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a perspective view of an exemplary univentricular assist device coupled to a redundant set of controllers and battery power sources. [Diagram 2] 1A-1C are sequential cross-sectional views of an exemplary uni-acting ventricular assist device illustrating its complete operating cycle. [Diagram 3] 1A-1C are sequential cross-sectional views of an exemplary uni-acting ventricular assist device illustrating its complete operating cycle. [Figure 4A] 1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 4B]1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 4C] 1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 5A] 1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 5B] 1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 5C] 1A-1C are sequential cross-sectional views of an exemplary double-acting ventricular assist device illustrating its complete operating cycle. [Figure 6] FIG. 1 is a connection diagram of an exemplary ventricular assist device utilized as a left ventricular assist device (LVAD) applied to a typical human heart. [Figure 7] FIG. 1 is a perspective view of an exemplary double-acting artificial heart embodiment coupled to a redundant pair of controllers. [Figure 8] FIG. 8 is a cross-sectional view of the artificial heart shown in FIG. 7 taken along section line 8-8 therein. [Figure 9] FIG. 1 is a perspective assembly view of an alternative embodiment of an artificial heart utilizing rotating coils for rotary shuttle motion and linear coils for linear motion. [Figure 10] FIG. 1 is a perspective assembly view of an artificial heart utilizing permanent magnets for movement of a rotating shuttle. [Figure 11A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 11B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 11C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 12A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 12B]1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 12C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 13A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 13B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 13C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 14A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 14B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 14C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 15A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 15B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 15C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 16A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 16B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 16C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 17A] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 17B] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 17C] 1 is a series of cross-sectional views of an exemplary artificial heart illustrating its complete operating cycle. [Figure 18] 1 illustrates the application of an exemplary artificial heart to an exemplary depiction of the human circulatory system. [Figure 19] 13 is a variation of the pump device utilizing an externally actuated four-way valve. [Figure 20A] 1 is a cross-sectional view of an exemplary device for pumping blood. [Figure 20B] FIG. 20B is a cross-sectional view of the device of FIG. 20A, with the housing, shuttle, and end caps shown separately. [Figure 21] An assembly diagram of the shuttle is shown. [Figure 22] 1 is a cross-sectional view of a channel in a shuttle showing a channel having one open end and one closed end. [Figure 23] 1 provides a close-up view of the clearance gap between the shuttle and the housing. [Figure 24A] 1 illustrates an assembly diagram of an exemplary ventricular assist device. [Figure 24B] 24B shows the ventricular assist device of FIG. 24A with a manifold attached. [Figure 25A] 1 shows a perspective view of an exemplary artificial heart. [Figure 25B] 25A-C show perspective views of an exemplary manifold for the cardiac prosthesis shown in FIG. 25A in an unlatched (FIG. 25B) and latched (FIG. 25C) configuration. [Figure 25C] 25A-C show perspective views of an exemplary manifold for the cardiac prosthesis shown in FIG. 25A in an unlatched (FIG. 25B) and latched (FIG. 25C) configuration. [Figure 26A] FIG 26A shows an example magnet that corresponds to the shape of a channel in a shuttle. FIG 26A provides a cross-sectional view of the example magnet, FIG 26B shows a cross-sectional view of the magnet of FIG 26A in a shuttle, and FIG 26C shows stacking several of the magnets of FIG 26A to form a magnet stack having the shape of the channel. [Figure 26B]FIG 26A shows an example magnet that corresponds to the shape of a channel in a shuttle. FIG 26A provides a cross-sectional view of the example magnet, FIG 26B shows a cross-sectional view of the magnet of FIG 26A in a shuttle, and FIG 26C shows stacking several of the magnets of FIG 26A to form a magnet stack having the shape of the channel. [Figure 26C] FIG 26A shows an example magnet that corresponds to the shape of a channel in a shuttle. FIG 26A provides a cross-sectional view of the example magnet, FIG 26B shows a cross-sectional view of the magnet of FIG 26A in a shuttle, and FIG 26C shows stacking several of the magnets of FIG 26A to form a magnet stack having the shape of the channel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Described herein are devices and methods for pumping blood to patients in need of circulatory assistance or replacement hearts. Instead of providing a temporary solution for these patients (recipients), the devices may be permanently implanted. As mentioned above, there are several features of the devices described herein that allow the devices to provide a permanent solution for these patients, such as, for example, the lack of an impeller that must rotate at high speeds to efficiently pump blood, a shuttle that uses primarily linear motion to generate blood flow, and materials used to make the components, which allow the components of the device to be precisely machined and achieve tight tolerances between the components. The tight tolerances achieved may prevent (or greatly reduce the amount of) red blood cells from moving between and damaging the device components, and minimize the number of components in the device. For example, the tight tolerances achieved in the device may completely eliminate the need for sealing in the device. The linear motion of the shuttle may further prevent damage to red blood cells, at least because it does not generate shear forces. Furthermore, because of its efficiency, it moves blood at a slower natural speed, thereby also preventing damage to red blood cells.

[0033] Devices for pumping blood The device for pumping blood described herein may function as a ventricular assist device or artificial heart. The device may generally include a housing with an outer surface, a plurality of ports, a first end, and a second end. The first and second ends may define a chamber therebetween, and the shuttle may be positioned within the chamber. The shuttle may include an outer sleeve defining a hollow interior surface, and one or more channels extending longitudinally along the outer sleeve. The device may further include a magnetic actuation system that may be operable to impart linear and rotational motion to the shuttle. The linear motion of the shuttle may serve to pump blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle may serve to selectively direct the flow of blood through the plurality of ports.

[0034] housing As described above, the devices described herein may generally include a housing, for example, a cylindrical housing, or a housing having an oval or rectangular cross-sectional shape. The housing may generally include a first end and a second end, which may be end caps used to enclose the housing and form a chamber therein. The chamber may be a fixed volume chamber, such that a shuttle moving within the chamber defines two separate variable volume portions. The housing may further include multiple ports (e.g., one or more inlet ports, one or more outlet ports) that may allow blood to move into and out of the housing. The ports may be included in any suitable area of ​​the housing, for example, in the center and / or at the end of the housing. Additionally, the ports may be positioned to correspond to the spacing of the inlets and outlets of the manifold, as described further below.

[0035] The size of the port may vary depending on factors such as the size of the housing, the intended recipient, and / or the number of ports included in the housing. For example, the diameter of the port may vary depending on the size of the housing. For example, the diameter of the port may be about 0.20 cm to about 0.60 cm. When the device is used as a ventricular assist device, two ports may be included, one for the movement of blood into the housing (inlet port) and one for the movement of blood out of the housing (outlet port). When the device is used as an artificial heart, four ports may be included, two for the movement of blood into the housing (first and second inlets) and two for the movement of blood out of the housing (first and second outlets). However, any suitable number of ports may be employed. For example, six, eight, or ten ports may be included in the housing.

[0036] The housing may be made of or include a ceramic material. Exemplary ceramic materials may include sapphire, synthetic variants of sapphire, zirconia, synthetic variants of zirconia, etc. The material may be ground and polished to achieve the lowest possible coefficient of friction. In some cases, the housing may be made of a metal, such as stainless steel, a stainless steel alloy, titanium, or a titanium alloy. In other examples, the housing may be made of or include a plastic material, or other suitable biocompatible material.

[0037] In some embodiments, the housing may include a coating on its outer surface. The coating may be made of any suitable biocompatible polymer. For example, polymers such as silicone, polyethylene, acrylic, polyurethane, and polypropylene may be used. However, when the housing is made of a ceramic material, such as sapphire or zirconia, the coating may not be required because these materials are biocompatible and non-immunogenic.

[0038] The dimensions of the housing may vary according to the person receiving the device, e.g., a child or an adult, or the size of the device. In general, a larger housing may be suitable for an adult recipient, and a smaller housing may be suitable for a pediatric recipient. The length of the housing may be about 5.0 cm to about 10 cm, including all values ​​and subranges therein. For example, the length of the housing may be about 5.0 cm, about 6.0 cm, about 7.0 cm, about 8.0 cm, about 9.0 cm, or about 10 cm. In variations in which a cylindrical housing is used, the diameter of the cylindrical housing may be about 1.5 cm to about 2.5 cm, including all values ​​and subranges therein. For example, the diameter of the cylindrical housing may be about 1.5 cm, about 2.0 cm, or about 2.5 cm.

[0039] The housing may be enclosed at each end by an end cap. The radius of curvature of the end cap may be configured such that its inner surface (i.e., the housing surface facing the chamber) is generally not flush with the outer surface (i.e., the shuttle surface) of the shuttle end cap. More specifically, the curvature of the housing surface may have a radius of curvature greater than the radius of curvature of the shuttle surface. Alternatively, the housing surface may be flat and the shuttle surface curved. As a result, the shuttle surface may be driven relative to the housing surface without conforming to it, thereby avoiding the creation of a vacuum attachment between them that may otherwise impede movement of the shuttle away from the housing surface or damage the red blood cells. When the housing surface is curved, it may have a radius of curvature of about 9 cm to about 10 cm, for example, about 9.86 cm (3.88 inches).

[0040] 20A and 20B, partial cross-sectional views of an exemplary pump device 200 are shown that include a housing or cylinder 202. Although the housing 202 is described as being cylindrical, other shapes may be employed. The housing 202 may include a number of ports 204 and end caps 206, 208 at a first end 210 and a second end 212 of the housing 202 that define a chamber 213 therebetween.

[0041] shuttle The devices described herein may generally include a shuttle disposed within a chamber of a housing. The shuttle, acting as a piston, may be linearly transported within the chamber to pump blood into and out of the housing. As the shuttle moves back and forth within the chamber, it may define two separate variable volume portions of a fixed volume chamber. The shuttle may include an outer sleeve, which may have a hollow interior surface, and first and second shuttle end caps positioned at opposite ends of the outer sleeve. The outer sleeve may be cylindrical.

[0042] The shuttle may include one or more magnets (shuttle magnets) positioned and retained within the hollow interior surface of the sleeve. The magnets may be used in combination with a magnetic actuation system, described in more detail herein, to actuate movement of the shuttle. In some variations, the shuttle may include a single magnet, while in other variations, the shuttle may include multiple magnets (e.g., two, three, four, five, six, seven, or more). In other variations, the shuttle may include a first rotational motion magnet at one end adjacent to a first linear motion magnet, along with a second rotational motion magnet at an opposite end adjacent to a second linear motion magnet.

[0043] In some cases, the shuttle magnets may be electromagnets. In some variations, the shuttle magnets may be permanent rare earth magnets, such as neodymium magnets. In these variations, the neodymium magnets may alternatively be arranged, for example, NS SN NS SN NS, where "S" refers to the south pole of the magnet and "N" refers to the north pole of the magnet, if five magnets are employed. The south poles of each adjacent magnet may face each other and the north poles of each adjacent magnet may face each other. In variations where a single magnet may be used, the single magnet may include a ceramic material that may be magnetized to produce the same arrangement. One or more shuttle magnets may be cylindrical. In other variations, the shape of the shuttle magnets may correspond to the shape of a channel in the outer sleeve of the shuttle. For example, referring to FIGS. 26A-26C, the magnets may be shaped to match or correspond to the shape of a channel in the shuttle, such as, for example, the shape of a shuttle having two channels. Thus, as shown in Figure 26A, the magnet 600 may be shaped to include an arcuate or rounded notch 602 that corresponds to the shape of the channel 604 (see cross-sectional view of shuttle 606 within housing 608 as shown in Figure 26B). The shape of the magnet 600 that corresponds to the shape of the channel 604 is further illustrated when multiple magnets 600 are provided within a magnet stack 610 as shown in Figure 26C.

[0044] The shuttle may further comprise one or more channels that may be formed in the outer sleeve. The one or more channels may extend longitudinally along the outer sleeve, but may be oriented in any suitable direction that allows blood flow to be selectively directed into and out of the housing. The shuttle may be configured to rotate so that the channels align with particular ports of the housing to selectively direct blood through the ports. For example, the shuttle may be rotated approximately 90 degrees to selectively direct blood from the inferior and superior vena cava to an inlet port of a housing fluidly coupled thereto, to selectively direct blood from a pulmonary vein to an inlet port of a housing fluidly coupled thereto, to selectively direct blood from the housing to the pulmonary artery through an outlet port fluidly coupled thereto, or to selectively direct blood from the housing to the aorta through an outlet port fluidly coupled thereto. In some embodiments, the shuttle selectively directs blood from the inferior and superior vena cava to the housing through an inlet port while simultaneously selectively directing blood from the housing to the pulmonary artery through an outlet port. In other embodiments, the shuttle selectively directs blood from the pulmonary veins through the inlet port into the housing and simultaneously directs blood from the housing through the outlet port into the aorta.

[0045] The dimensions of the shuttle typically vary according to the dimensions of the housing. The shuttle may have a length of about 5.0 cm to about 6.0 cm, including all values ​​and subranges therein. For example, the shuttle length may be about 5.0 cm, about 5.5 cm, or about 6.0 cm. In variations with a cylindrical outer sleeve, the shuttle may have a diameter of about 3.5 cm to about 4.5 cm, including all values ​​and subranges therein. For example, the shuttle diameter may be about 3.5 cm, about 4.0 cm, or about 4.5 cm.

[0046] The shuttle may be made from or include the same material as the housing, and generally may be precisely machined so that seals (e.g., O-rings) do not need to be included in the device. For example, the housing, the shuttle, or both may generally be made from a material that can be precisely machined. In one embodiment, the material may be a ceramic material. Exemplary ceramic materials may include, but are not limited to, sapphire or synthetic variants thereof, and zirconia or synthetic variants thereof. In one embodiment, the housing may be made entirely or partially from a sapphire material. In another embodiment, the shuttle may be made entirely or partially from a sapphire material. In yet another embodiment, both the housing and the shuttle may be made entirely or partially from a sapphire material. In other embodiments, the shuttle and the housing may be constructed from a material such as titanium, an alloy of titanium alloys, stainless steel, an alloy of stainless steel, plastic, or other suitable biocompatible material.

[0047] The ability to precisely machine the housing and shuttle may allow for a tight or tight fit between the components, thus minimizing clearance gaps formed between the components (e.g., between the outer surface of the shuttle and the inner surface of the housing (e.g., chamber)). In one embodiment, the clearance gap may be less than about 5.0 μm. In another embodiment, the clearance gap may be less than about 4.0 μm. In a further embodiment, the clearance gap may be less than about 3.0 μm. In yet another embodiment, the clearance gap may be from about 2.0 μm to about 4.0 μm, including all values ​​and subranges therein. In some embodiments, the clearance gap may be about 2.0 μm, about 2.5 μm, about 3.0 μm, about 3.5 μm, or about 4.0 μm. In other embodiments, the clearance gap may be sized to prevent passage of red blood cells between the inner surface of the housing and the outer surface of the shuttle.

[0048] The shuttle may include one or more channels that may extend longitudinally along the outer surface (i.e., outer sleeve) of the shuttle. Each channel of the plurality of channels may have one open end and one closed end to aid in the movement of blood into and out of the housing, as described further below. Additionally, each channel of the plurality of channels may include only rounded edges that may prevent or minimize damage to the red blood cells as they are pumped through the housing. The dimensions of the channels may vary with the dimensions of the shuttle. In general, the channels may have a length of about 4.0 cm to about 5.0 cm and a depth of about 0.5 cm to about 0.6 cm. In some variations, the shuttle may include two channels. In these variations, the two channels may be arranged about 90 degrees apart on the surface of the shuttle, or may be arranged about 180 degrees apart on the surface of the shuttle.

[0049] Returning to Figures 20A and 20B, there is shown a shuttle 214 positioned within the housing 202 of the pump device 200. As described herein, the shuttle 214 may function as a piston that reciprocates back and forth to pump blood. The shuttle 214 includes an outer sleeve 216 defining a hollow interior surface 217, and a shuttle end cap 218 at each end of the sleeve 216, as better shown in Figure 21. A channel 220 is also provided extending longitudinally along the outer sleeve 216. Referring to Figure 22, an enlarged view of the channel 220 is shown having one closed end 222 and one open end 224. As will be further described below, the closed and open ends help facilitate the flow of blood into and out of the housing.

[0050] 23, an exemplary device 300 is shown including a housing 302 and a shuttle 304 contained within the housing 302. The circled area 306 is shown enlarged to show a small clearance gap 308 between the housing 302 and the shuttle 304. In this variation, the clearance gap may generally be from about 2 μm to about 4 μm.

[0051] The shuttle end cap (i.e., shuttle face) may have a smaller radius of curvature than the housing face. As a result, the shuttle face may be driven relative to the housing face without conforming to the housing face, thereby avoiding the creation of a vacuum attachment between them that may otherwise impede movement of the shuttle away from the housing face. In some embodiments, the shuttle face has a radius of curvature between about 1.0 inches and about 4.0 inches. In one embodiment, the shuttle face has a radius of curvature of about 3.17 inches.

[0052] 20A and 20B, partial cross-sectional views of an exemplary pump device 200 are shown that include a housing or cylinder 202. Although the housing 202 is described as being cylindrical, other shapes may be employed. The housing 202 may include a number of ports 204 and end caps 206, 208 at a first end 210 and a second end 212 of the housing 202 that define a chamber 213 therebetween.

[0053] As a result, the shuttle surface may be driven relative to the housing surface without conforming to the housing surface, thereby avoiding the creation of a vacuum attachment therebetween that may otherwise impede movement of the shuttle away from the housing surface. In one embodiment, the housing surface may be curved, where the housing surface may have a radius of curvature of about 3.88 inches. In another embodiment, the housing surface is flat, i.e., has no radius of curvature.

[0054] Magnetic Actuation System As previously described, the shuttle in the chamber moves linearly according to a pumping cycle to pump blood into and out of the chamber and rotates to selectively direct the flow of blood through the housing's multiple ports. Both the linear and rotational motion of the shuttle can be achieved using a magnetic actuation system. In one embodiment, as further described below, the magnetic actuation system can include multiple linear motor coils surrounding the housing and multiple rotating coils disposed at the first and second ends of the housing, each of which can interact with one or more magnets (shuttle magnets) disposed within the inner surface of the outer sleeve. For example, the coils can be energized to generate a magnetic field that can interact with the shuttle magnets to effect shuttle movement. In some variations, a bank of three coils can generally be sufficient to form a complete drive unit for the magnetic actuation system. However, depending on the location of the ports, two or three coil drive units can be used. In some embodiments, the magnetic actuation system can include multiple linear motor coils that can provide redundancy so that the device still functions if one coil fails.

[0055] The interaction between the shuttle magnets and the linear motion coils causes the shuttle to reciprocate linearly, and the interaction between the shuttle magnets and the rotating coils causes the shuttle to rotate. In another embodiment, also described further below, the magnetic actuation system may include a plurality of magnets disposed within an inner surface of an outer sleeve, a plurality of linear motor coils surrounding the housing, and a permanent magnet disposed within each of the first and second ends of the housing. In this embodiment, the interaction between the shuttle magnets and the linear motion coils causes the shuttle to reciprocate linearly, and the interaction between the shuttle magnets and the permanent magnets causes the shuttle to rotate. The energization of the coils to generate the magnetic field that drives the movement of the shuttle may be accomplished using a three-phase AC power supply, the phase of which may be switched depending on the direction of drive / movement required, and the amplitude may be adjusted depending on the drive force required. In other embodiments, a 12-volt, 24-volt, or 48-volt DC power supply may be used.

[0056] Generally, the magnetic field generated within the core of the drive coil may be proportional to the amount of current flowing through the coil. For example, when the coil is a flattened donut with a wire wound around a hole, a strong magnetic field may be generated within the hole when current flows through the coil, which may be represented as an arrow pointing out of the hole. The direction of the magnetic field, i.e., the tip of the arrow, reverses when the direction of the current is reversed. This magnetic field interacts with the magnetic field of the magnets in the shuttle, e.g., permanent neodymium magnets, which may be very strong, e.g., due to stacking. For example, in a variation utilizing permanent magnets, the permanent magnets may be stacked such that the north and north poles of adjacent magnets face each other and the south and south poles of adjacent magnets face each other. By appropriately manipulating the current through the drive coil, the interacting magnetic fields may provide an axial force in the appropriate direction, either repulsive or attractive, as needed, to drive the pumping action of the shuttle. The rotational force that rotates the shuttle may be generated by separate coils at each end of the housing and may be actuated by the pump controller independently of the linear magnetic drive.

[0057] manifold In some variations, the pumping device may be used with or include a manifold. For example, in these variations, the housing may be generally associated with a manifold that may be configured to help direct the flow of blood between the housing and the appropriate anatomical structure of the recipient (e.g., the inferior or superior vena cava, the pulmonary artery, the pulmonary vein, the aorta, or the left ventricle). Additionally, the manifold may include one or more inlets and one or more outlets, whereby the vasculature of the recipient, the left ventricle, or other appropriate anatomical structure may be connected to the housing. The inlets and outlets may be in fluid communication with ports corresponding to the multiple housing ports. For example, when the device is a ventricular assist device, the manifold may include a single inlet and a single outlet, and when the device is an artificial heart, the manifold may include a pair of inlets (first and second inlets) and a pair of outlets (first and second outlets). When the manifold is part of or used with a ventricular assist device, the single inlet of the manifold may be in fluid communication with the recipient's left ventricle and the single outlet of the manifold may be in fluid communication with the recipient's aorta. When the manifold is part of or used with a heart artificial, the first inlet may be in fluid communication with the recipient's inferior or superior vena cava and the second inlet may be in fluid communication with the recipient's pulmonary veins. Additionally, the first outlet may be in fluid communication with the recipient's pulmonary artery and the second outlet may be in fluid communication with the recipient's aorta.

[0058] The spacing of the manifold inlets and outlets may be configured such that the manifold inlets and outlets generally align with corresponding ports in the housing. In some embodiments, for example, when the device is a ventricular assist device, the single inlet and single outlet may be spaced apart by about 90 degrees on the exterior surface of the housing. In other embodiments, for example, when the device is an artificial heart, the first and second inlets of the manifold may be spaced apart by about 90 degrees on the exterior surface of the housing. Similarly, the first and second outlets of the manifold may be spaced apart by about 90 degrees on the exterior surface of the housing.

[0059] In some variations, the manifold may be integrally formed with the housing, while in other variations, the manifold may be formed separately from the housing and coupled to the housing, for example, using an attachment mechanism. For example, in some variations, the manifold may include an attachment mechanism in the form of a flexible strip or band of material that is disposed around the housing. Ends of the strip or band may be secured together with latches or other suitable fastening components. The manifold may be made from a suitable biocompatible material, such as, for example, stainless steel or titanium. The attachment mechanism may be made from the same material as the manifold, or a different material (e.g., a flexible polymer such as polyethylene, polyethylene terephthalate, polyvinyl chloride, polypropylene, or polystyrene).

[0060] A manifold is also generally included in the pump devices described herein that helps direct the flow of blood to and from the housing and to the appropriate anatomical structures of the recipient. When the device is a ventricular assist device, the single inlet of the manifold may be in fluid communication with the left ventricle of the recipient and the single outlet of the manifold may be in fluid communication with the aorta of the recipient. The single inlet and single outlet of the manifold may be in fluid communication with corresponding inlet and outlet ports of the housing. For example, as shown in FIGS. 24A and 24B, a ventricular assist device 400 includes a housing 402 having an inlet port 404 and an outlet port (not shown). A manifold 408 may be coupled to the housing 402 by an attachment mechanism, i.e., a strap 410. The strap 410 may be secured around the housing 402 using a fastener or plug 412. When fastened, the inlet port 404 and the outlet port may be aligned with the corresponding inlet 401 and outlet 403 of the manifold 408. The fastener 412 has a groove 414 that corresponds to a rail 416 provided on the end of the strap 410. A set screw 418 may be disposed in an opening 420 to further secure the attachment of the manifold 408 to the housing 402.

[0061] As shown in FIG. 25A, when the device is an artificial heart 500, the housing 502 may be coupled to a manifold 504, as shown in FIG. 25B and 25C. Referring to FIG. 25B, the manifold 504 includes a pair of inlets, first and second inlets 506, 508, and a pair of outlets, first and second outlets 510, 512. The first inlet 506 may be in fluid communication with the recipient's inferior or superior vena cava, and the second inlet 508 may be in fluid communication with the recipient's pulmonary veins. Additionally, the first outlet 510 may be in fluid communication with the recipient's pulmonary artery, and the second outlet 512 may be in fluid communication with the recipient's aorta. The manifold 504 may be coupled to the housing 502 by an attachment mechanism, i.e., a strap 514. Upon fastening, the manifold inlets 506, 508 and outlets 510, 512 may be in fluid communication with corresponding inlet and outlet ports (not shown) of the housing 502. The strap 514 may be secured around the housing 502 using fasteners or plugs 516. Similar to the ventricular assist device, the fasteners 516 may have grooves (not shown) that correspond to rails 518 provided on the ends of the straps 514. Similarly, set screws (not shown) may be placed in the openings 520 to further secure the attachment of the manifold 514 to the housing 502.

[0062] The devices for pumping blood described herein can function as ventricular assist devices or artificial hearts. Although the devices are similar in structure, ventricular assist devices generally include a manifold with a single inlet and a single outlet, connected to the left ventricle and aorta of the recipient. On the other hand, artificial heart devices generally include a manifold with first and second inlets and first and second outlets. The first and second inlets can be connected to the inferior and superior vena cava and pulmonary veins of the recipient, respectively, and the first and second outlets can be connected to the pulmonary artery and aorta of the recipient, respectively. Additional details of ventricular assist devices and artificial hearts are provided below.

[0063] controller The devices described herein may also include one or more controllers operably coupled to the magnetic actuation system, which may be configured to control the pumping cycle of the device, for example, to control or adjust the speed of the pumping cycle (e.g., the speed of the shuttle and the rotational speed of the shuttle). In some variations, the device may include two or more (e.g., three, four, or more) controllers such that the device has redundancy at which the controller should cease operation. In addition to being operably coupled to the magnetic actuation system, the controller may be operably coupled to one or more sensors on the device. For example, in some variations, the device may include one or more (e.g., two, three, four, or more) pressure sensors operably coupled to the controller, with blood pressure data provided to the controller. The number of pressure sensors included in the device may be configured to provide redundancy. When the pressure sensor detects a blood pressure lower than a predetermined diastolic blood pressure, the controller may automatically increase the speed of the pumping cycle. Similarly, when the pressure sensor detects a blood pressure higher than a predetermined systolic blood pressure, the controller may automatically decrease the speed of the pumping cycle. The one or more pressure sensors may be positioned at any suitable location on the device, but are typically located near, inside, or on the outlet of the manifold. In one embodiment, for example, when the device is an artificial heart, four pressure sensors may be included in the device. Four pressure sensors may provide redundancy should one of the sensors cease operation. Here, two sensors may be located at each of the two outlets of the manifold.

[0064] The controller may be configured to be implanted in the recipient or may be configured to remain external to the body. In both embodiments, the controller may include a Bluetooth system operable to transmit information about the pumping device to an external device, such as another device, e.g., a computer, cell phone, tablet, or other handheld or portable device. In some embodiments, the controller may include a telemetry system operable to transmit and receive information about the pumping device to and from an external device, such as another device, e.g., a computer, cell phone, tablet, or other handheld or portable device.

[0065] One or more rechargeable batteries may also be provided with the devices described herein. In some variations, the devices described herein may include more than one battery (three, four, or more) so that the device has redundancy when the battery should cease operation. In one embodiment, given that the battery typically generates DC power, an inverter may be connected to it to convert the DC power to AC current required for the magnetic actuation system, controller, etc. The battery may be charged via near-field inductive charging with a charging device worn by the recipient near the implanted device. Additionally or alternatively, the battery may be charged wirelessly using an antenna that receives a signal from a far-field emitter, which is then converted into a signal capable of charging the battery. Far-field charging may occur at distances of up to about 20 feet from the emitter.

[0066] Ventricular Assist Devices As discussed above, the ventricular assist device described herein may generally include a cylindrical housing with an outer surface, a single inlet port, a single outlet port, a first end, and a second end, the first and second ends defining a chamber therebetween. A shuttle may be provided within the chamber. The shuttle may include an outer sleeve defining a hollow inner surface containing a plurality of magnets, and one or more channels extending longitudinally along the outer sleeve. The ventricular assist device may further include a magnetic actuation system operable to impart linear and rotational motion to the shuttle, the linear motion of the shuttle pumping blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directing the flow of blood through the single inlet port and the single outlet port. Additionally, the device may include a manifold including a single inlet and a single outlet, both of which are in fluid communication with a corresponding single inlet port and a corresponding single outlet port.

[0067] FIG. 1 reveals a perspective view of a single action ventricular assist device 10. The ventricular assist device 10 is connected by cable 16 to a controller 20 having a battery power source 21. The ventricular assist device 10 is further connected by cable 17 to a backup controller 22 having a backup battery power source 23. The duplicated set of controllers and battery power sources improves the reliability of the ventricular assist device 10. The ventricular assist device 10 together with the controllers 20 and 22 and the batteries 21 and 23 may be implanted in their entirety within the patient recipient or, alternatively, may be distributed with selected components remaining external to the patient recipient. The ventricular assist device 10 generally includes a cylindrical housing 11 having integrally formed ends 12 and 13. In one variation of its manufacture, the housing 11 including the ends 12 and 13 is formed from a biocompatible encapsulating material that is molded over an operating structure (seen in FIG. 8) that will be revealed below. Housing 11 further supports an input coupler 14 and an output coupler 15 , each of which operates in a manner to be revealed below, to enable the transfer of blood to and from ventricular assist device 10 .

[0068] In operation, the ventricular assist device 10 is coupled to a patient's circulatory system at a point where it is desired to improve or increase blood flow. One common point of use for the ventricular assist device 10 is shown below in FIG. 6, in an application commonly referred to as left ventricular assist. Typically, the ventricular assist device 10 is positioned to increase blood flow between selected portions of the patient's circulatory system. When the controller 20 provides an operable electrical signal to a driver (disclosed in FIG. 8 below), blood is drawn into the ventricular assist device 10 via input coupler 14 and then pumped outward via output coupler 15.

[0069] 2A-2C together with FIG. 3A-3C reveal sequential diagrams showing the operation cycle of the ventricular assist device 10. It is noted that the diagrams shown are simplified to more clearly illustrate and understand the operation cycle of the ventricular assist device 10. It is therefore understood that certain operating structures have been omitted from FIG. 2A-2C as well as FIG. 3A-3C to avoid over-cluttering the drawings and to more easily understand the operation of the ventricular assist device 10. With momentary reference to FIG. 8, 9 and 10, it will be seen that the ventricular assist device 10 is driven in linear motion by a number of linear motor coils surrounding a cylinder with permanent magnets disposed within the inner surface of the shuttle. In addition, it is equally clear that the rotation of the shuttle during operation described below is induced by either an additional rotational drive coil also disposed on the cylinder or alternatively a coordinated set of permanent magnets disposed on the shuttle and the end cap of the cylinder. In any event, it is understood that in the following description, it is assumed that such a system is operating and that their functions are performed in the manner described below.

[0070] Returning to and simultaneously referring to FIGS. 2A-2C and 3A-3C, the ventricular assist device 10 includes a cylinder 24 defining a cylinder bore 25 therethrough. The cylinder 24 further defines closed ends 34 and 35. The cylinder 24 also supports an input coupler 14 and an output coupler 15, both of which are in communication with an inner surface of the cylinder bore 25. The shuttle 26 is generally cylindrical and precisely mounted within the cylinder bore 25 so as to be freely movable therein. The shuttle 26 further defines a face 36 and a face 37. The cylinder head 28 comprises a volume within the cylinder bore 25 enclosed by the closed end 34 of the shuttle 26 and the face 36 together with a portion of the cylinder bore 25 therebetween. The shuttle 26 also defines a blood flow channel 27 that is open at face 36 and closed at face 37.

[0071] FIG. 6 reveals a connection diagram of a ventricular assist device utilized as a left ventricular assist device (LVAD), generally referenced by the numeral 78, applied to a typical human heart, generally referenced by the numeral 75. Heart 75 is representative of a typical human heart, and as such includes a left ventricle 76 and an aorta 77. In accordance with normal connections for left ventricular assist device applications, ventricular assist device 78 is coupled to the lower end of left ventricle 76 by a flexible braided hose 73. In further accordance with conventional use, ventricular assist device 78 is coupled to aorta 77 by a flexible braided hose 74. In this application, ventricular assist device 78 may comprise ventricular assist device 10 shown in FIG. 1, or alternatively, ventricular assist device 50 as shown and described above in FIGS. 4A-5C. In any event, basic ventricular assist is provided as the left ventricular assist device 78 flows blood from the lower end of the left ventricle 76 and pumps it through the braided hose 74 into the aorta 77 at increased pressure and strength to compensate for the possibly impaired performance of the left ventricle 76. Although not seen in FIG. 6, it will be understood that the left ventricular assist device 78 is connected to operational controls and power sources in the manner described above. Alternatively, the device may be implanted within the patient, or external to the patient in the case of connections made by multiple connecting wires (seen in FIG. 1).

[0072] Artificial Heart Device The artificial heart device described herein may generally include a cylindrical housing with an exterior surface, first and second inlet ports, first and second outlet ports, a first end, and a second end, the first and second ends defining a chamber therebetween. A shuttle may be contained within the chamber, the shuttle may include an outer sleeve defining a hollow interior surface containing a plurality of magnets therein, and one or more channels extending longitudinally along the outer sleeve. The artificial heart may further include a magnetic actuation system operable to impart linear and rotational motion to the shuttle, the linear motion of the shuttle pumping blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directing the flow of blood through the first and second inlet ports and the first and second outlet ports. The device may also include a manifold associated with the cylindrical housing, the manifold including first and second inlets and first and second outlets, the first and second inlets and first and second outlets in fluid communication with ports corresponding to the first and second inlet ports and the first and second outlet ports.

[0073] FIG. 7 reveals a perspective view of an exemplary double acting artificial heart 80 coupled to a redundant pair of controllers 90 and 91. The artificial heart 80 may be coupled to the controllers 90 and 91 by a pair of cables 92 and 93, respectively. As described above for the ventricular assist device, the coupling of the artificial heart 80 via the cables 92 and 93 is understood to be representative of either an implanted placement of the controllers 90 and 91, or alternatively, an external controller 90 and 91. In the case where the controller is external to the patient, the connection to the artificial heart 80 implanted within the patient may be provided by the cables 92 and 93 passing through the patient's skin. The artificial heart 80 may be generally cylindrical in shape and may optionally include an outer coating or layer of a biocompatible material 85. In one variation of the artificial heart including a biocompatible coating or layer, the coating or layer 85 may be molded onto the artificial heart 80 to completely seal and protect the artificial heart device. A pair of inlet or input couplers 81 and 82 are supported on the artificial heart 80 and are spaced apart at an angular interval of 90°. A pair of outlet or output couplers 83 and 84 are similarly supported on the artificial heart 80 and are also spaced apart at an angular interval of 90°. The 90° angular spacing between the inlets and outlets is provided to be compatible with 90° angular rotation increments applied to the shuttle in a manner described in more detail below.

[0074] FIG. 8 reveals a cross-sectional view of an artificial heart 80 similar to that revealed above in FIG. 7, taken along section line 8-8 therein. The artificial heart 80 includes a shuttle 110 movable within a cylinder 85. The cylinder 85 defines a cylinder bore 86 having a pair of end caps 87 and 88 joined at both ends thereof. The combination of the cylinder 85 and the end caps 87 and 88 forms a closed-ended cylinder within which the shuttle 110 is freely movable and precisely mounted. The shuttle 110 includes a magnet support sleeve 111 defining a pair of blood flow channels 121 and 122. The shuttle 110 further includes a plurality of linear motion magnets 115, 116, 117 and 118 supported within the magnet support sleeve 111 and secured by mutual magnetic attraction, and in some cases, conventional adhesives or other attachments. The shuttle 110 further supports a rotary motion magnet 119 adjacent to a linear motion magnet 118 at one end, along with a linear motion magnet 115 adjacent to a rotary motion magnet 120 at the opposite end. The structure of the shuttle 110 is completed by an end cap 112 secured to the rotary motion magnet 119 adjacent to the magnet support sleeve 111, along with an end cap 113 secured to the rotary motion magnet 120 adjacent to the magnet support sleeve 111. The end caps 112 and 113 are bonded to the magnet support sleeve 111 and the magnets 119 and 120 using conventional biocompatible adhesives or similar attachments.

[0075] The artificial heart 80 further includes an input section 82 and an output section 83, both of which extend into the cylinder bore 86. A plurality of linear motion coils 100 are wound on the outer surface of the cylinder 85. A plurality of rotary motion coils 101 are wound on one end of the cylinder 85, while a second plurality of rotary motion coils 102 are wound on the opposite end of the cylinder 85. The linear motion coils 101 and the rotary motion coils 101 and 102 are each coupled to a controller (seen in FIG. 7) that provides appropriate electrical signals to drive the artificial heart 80. As described above, the artificial heart 80 is coated with an outer molded encapsulation (seen in FIG. 1) that seals and protects the components within the artificial heart 80.

[0076] In operation, reciprocating linear motion is imparted to shuttle 110 within cylinder bore 86 by energizing linear motion coil 100. Similarly, rotational motion is imparted to shuttle 110 by energizing rotary motion coils 101 and 102 at both ends of shuttle 110's movement. Cylinder head volume 106 is defined between face 104 of end cap 88 and face 123 of end cap 113, along with a portion of cylinder bore 86 therebetween. Thus, the volume of cylinder head 106 is determined by the linear position of shuttle 110 within cylinder bore 86. According to one embodiment, the curvature of face 104 defines a radius of curvature that is greater than the radius of curvature of face 123. As a result, shuttle 110 can be driven relative to face 104 without conforming to face 104, thereby avoiding the creation of a vacuum attachment therebetween that would otherwise impede movement of shuttle 110 away from face 104.

[0077] Similarly, cylinder head volume 105 is defined between face 104 of end cap 87 and face 124 of end cap 112, with a portion of cylinder bore 86 therebetween. The volume of cylinder head 105 is therefore determined by the linear position of shuttle 110 within cylinder bore 86. Again, the curvature of face 103 defines a radius of curvature that is greater than the radius of curvature of face 124. As a result, shuttle 110 can be driven relative to face 104 without conforming to it, thereby avoiding a vacuum attachment therebetween that would otherwise impede movement of shuttle 110 away from face 103.

[0078] FIG. 9 reveals a perspective assembly view of artificial heart 80. Artificial heart 80 includes a shuttle 110 (seen in FIG. 8) fabricated from a plurality of linear motion magnets 116, 117, and 118 along with a pair of rotational motion magnets 119 and 120 joined together to form a magnet stack. A sleeve 111, which defines a pair of blood flow channels 121 and 122, receives magnets 116-120. A pair of end caps 112 and 113 are attached to the magnet support sleeve 111 (seen in FIG. 8) to complete shuttle 110.

[0079] The artificial heart 80 further includes a cylinder 85 defining a cylinder bore 86 therethrough. The shuttle 110 is received within the cylinder bore 86, after which end caps 87 and 88 are secured to the ends of the cylinder 85 to complete its closed end configuration and capture the shuttle 110 (seen in FIG. 8). The cylinder 85 further defines openings 95 and 96 that receive the output portion 83 and the input portion 82 (seen in FIG. 8). Although not seen in FIG. 9, it will be noted by momentary reference to FIG. 7 that the artificial heart 80 further includes an input portion 81 and an output portion 84. It will thus be understood that the cylinder 85 further defines a pair of openings similar to the openings 95 and 96 on either side thereof that accommodate the input portion 81 and the output portion 84. Returning to FIG. 9, the linear motion coils 100A and 100B combine to form the linear motion coil 100, which are supported on either side of the openings 95 and 96. Rotary motion coils 101 and 102 are attached to the ends of cylinder 85. Once assembly of artificial heart 80 is complete, an outer protective covering of a biocompatible material (not shown) is formed over the entire exterior surface of artificial heart 80 in a process such as injection molding.

[0080] In some embodiments of the described devices, a close tolerance or precision fit is provided between the shuttle and the cylinder bore, which minimizes the clearance gap between the shuttle and the cylinder bore. The shuttle remains freely movable both laterally and rotationally within the cylinder bore, and the shuttle and cylinder bore remain free of additional sealing devices such as O-rings, gaskets, elastomeric seals, diaphragms, etc. Instead, the above described devices manufacture the shuttle's cylinder and magnet support sleeve from ceramic materials such as synthetic sapphire or zirconia. In addition, the precision machining of both the cylinder bore and the magnetic support sleeve is very accurate such that the clearance between the outer surface of the magnet support sleeve and the inner surface of the cylinder bore is maintained between two to three microns (2.0 to 3.0 μm). This clearance gap is smaller than the typical size of a blood cell. Thus, when blood is pumped into the ventricular assist device and artificial heart, blood cells do not move between the outer surface of the magnet support sleeve and the inner surface of the cylinder bore.

[0081] Returning specifically to FIG. 9 and considering the above description of the precision fit between the shuttle outer surface and the cylinder bore, it will be appreciated that when the shuttle 110 (seen in FIG. 8) is fully assembled and the outer surface of the magnet support sleeve 111 is precisely machined, the cylinder bore 86 of the cylinder 85 is also precisely machined such that the above-mentioned 2.0 to 3.0 micron clearance exists between the magnet support sleeve 111 and the cylinder bore 86. Once the shuttle 110 (seen in FIG. 8) is received within the cylinder bore 86, the end caps 87 and 88 are secured to the ends of the cylinder 85. The above-described output and input sections are then bonded to the cylinder 85, and finally, the linear motion coils 100A and 100B are positioned on the outer surface of the cylinder 85 along with the rotary motion coils 101 and 102 and the appropriate electrical connections (not shown) are made. Assembly is complete when the above-mentioned outer coating of biocompatible material is molded or otherwise placed on the outside of the artificial heart 80 to seal the entire structure.

[0082] In operation, the artificial heart 80 operates to move the shuttle 110 (seen in FIG. 8) in a linear motion within the cylinder bore 86 under the influence of the linear motion coils 100A and 100B as the linear motion coils 100A and 100B interact with the linear motion magnets 115-118. Similarly, the shuttle 110 undergoes a rotational motion at each end of its linear motion, in a manner described below, by the interaction of each of the rotary magnets supported at each end of the shuttle 110. Thus, as the shuttle 110 approaches the end 87, the rotary magnet 119 supported on the shuttle 110 interacts with the rotary motion coil 101 to provide a rotational motion of the shuttle 110, which will be described in more detail below. Similarly, as the shuttle 110 approaches the end cap 88 within the cylinder bore 86, the rotary magnet 120 interacts with the rotary motion coil 102 to induce a rotational motion of the shuttle 110, which will be described below. The linear and rotational operational movements that make up the operating cycle of both artificial heart 130 (seen in FIG. 10) and artificial heart 80 are elucidated in more detail below in FIGS. 11A-17C.

[0083] FIG. 10 reveals a perspective assembly view of an alternative embodiment of an artificial heart generally referenced by the numeral 130. The artificial heart 130 is substantially similar to the artificial heart 80 with the difference being the utilization in the artificial heart 130 of a coordinated pair of permanent magnets to provide rotation of the shuttle 160 rather than the combination of rotary motion coils and coordinated magnets utilized in the artificial heart 80. In all other respects, however, the function and operation of the artificial heart 130 is substantially the same as the artificial heart 80. The artificial heart 130 includes a shuttle 160 fabricated from a plurality of linear motion magnets 166, 167, 168, 169 and 170 joined together to form a magnet stack. The shuttle 160 further includes a pair of rotary motion magnets 119 and 120 supported within end caps 162 and 163, respectively. A magnet support sleeve 161 defining a pair of blood flow channels 171 and 172 receives the magnets 166-170. End caps 162 and 163 are attached to magnet support sleeve 161 to complete shuttle 160. Rotary magnet 120 is received within a recess 165 formed in the inner surface of end cap 163. Although not seen in FIG. 10, it will be understood that end cap 162 is identical to end cap 163 and therefore defines a recess similar to recess 165 which receives rotary magnet 119.

[0084] The artificial heart 130 further includes a cylinder 135 defining a cylinder bore 136 therethrough. A shuttle 160 is received within the cylinder bore 136, after which end caps 137 and 138 are secured to the ends of the cylinder 135 to complete its closed end structure and capture the shuttle 160. The cylinder 135 further defines openings or ports 145 and 146 for receiving the outlets and inlets of a manifold (not shown). Although not seen in FIG. 10, it will be noted by momentary reference to FIG. 7 that the artificial heart 80 further includes an additional input and an additional output. It will thus be understood that the cylinder 135 further defines a pair of openings similar to the openings 145 and 146 on either side thereof that accommodate the additional inputs and outputs. The linear motion coils 150A and 150B are combined to form a linear motion coil 150 supported on either side of the openings 145 and 146. End caps 137 and 138 are joined to the ends of cylinder 135 to capture shuttle 160 within cylinder bore 136. Note that end cap 138 defines a recess 139 which receives rotary magnet 140. Although not seen in FIG. 10, it will be understood that end cap 137 is identical to end cap 138 and therefore defines a magnet receiving recess identical to recess 139. Rotary magnet 141 will therefore be understood to be received within and supported within end 137. Once assembly of artificial heart 130 is complete, an outer protective covering of a biocompatible material (not shown) is formed over the entire exterior surface of artificial heart 130 in a process such as injection molding.

[0085] In operation, the artificial heart 130 operates to move the shuttle 160 in a linear motion within the cylinder bore 136 under the influence of the linear motion coils 150A and 150B as they interact with the linear motion magnets 166-170. Similarly, the shuttle 160 undergoes a rotational motion at each end of its linear motion, in a manner described below, by the interaction of each of the pairs of rotary magnets supported at each end of the artificial heart 130. Thus, as the shuttle 160 approaches the end 137, the rotary magnet 119 supported on the shuttle 160 in the end cap 162 interacts with the rotary magnet 141 supported in the end cap 137 to provide the rotational motion of the shuttle 160, which is described in more detail below. Similarly, as shuttle 160 approaches end cap 138 in cylinder bore 136, rotary magnet 140 in end cap 138 interacts with rotary magnet 120 supported on shuttle 160 in end cap 165 to induce rotational motion of shuttle 160 as described below. The linear and rotational operational movements that make up the operating cycles of both artificial heart 80 (seen in FIG. 9) and artificial heart 130 are elucidated in more detail in FIGS. 11A-17C below.

[0086] FIG. 11A reveals a cross-sectional view of the artificial heart 80 taken along the section lines 11A, 17A-11A, 17A of FIG. 7. FIG. 11B reveals a cross-sectional view of the artificial heart 80 taken along the section lines 11B-11B of FIG. 11A. FIG. 11C reveals a cross-sectional view of the artificial heart 80 taken along the section lines 11C-11C of FIG. 11A. FIG. 11A reveals an end view of the artificial heart 80 that facilitates illustration of the rotational positions of the shuttle 110 and the blood flow channels 121 and 122 formed therein relative to the inputs 81 and 82 and the outputs 83 and 84 of the artificial heart 80. The cross-sectional view of FIG. 11B facilitates illustration of the motions within the artificial heart 80 as the shuttle 110 moves within the cylinder bore 86 relative to the inputs 82 and the outputs 83. Finally, the cross-sectional view of Figure 11C facilitates illustration of the action within the artificial heart 80 as the shuttle 110 moves within the cylinder bore 86 relative to the input 81 and output 84. Taken together, Figures 11A, 11B, and 11C show the operation of the artificial heart 80 at specific points during its operating cycle. Similarly, Figures 12A-12C, 13A-13C, 14A-14C, 15A-15C, 16A-16C, and 17A-17C provide illustrations of other points within the operating cycle of the artificial heart 80.

[0087] While it will be understood that the operation of the artificial heart 80 is a continuous operation in which the operating cycle described below is continually repeated, it is believed that the operation of the artificial heart 80 may be more easily understood by examining the sequence of selected points within the operating cycle. The selected points within the operating cycle, as well as the starting and ending points selected for the purposes of the following description, are purely arbitrary and have been chosen for convenience.

[0088] Thus, with simultaneous reference to Figures 11A, 11B, and 11C, an artificial heart 80 is shown in a simplified depiction including a cylinder 85 in which a shuttle 110 is captured. The shuttle 110 defines blood flow channels 121 and 122. The cylinder 85 supports inputs 81 and 82 along with outputs 83 and 84. At the point in the operating cycle shown in Figures 11A-11C, the shuttle 110 rotates to align the blood flow channel 121 with the input 82 and the blood flow channel 122 with the output 83. At this operating point, the shuttle 110 has just completed a linear movement to the right and is positioned against the end 126 of the cylinder 85. With the movement to the right terminating at this position, the alignment of the blood flow channel 121 with the input 82 during this movement has caused blood flow into the cylinder head volume 127, completely filling the cylinder head 127. At the same time, the movement to the right by the shuttle 110 also completely displaces the blood volume within the cylinder head 128, which therefore defines a minimum volume. This defines a selected starting point or instantiation of the operating cycle of the artificial heart 80. Again, this starting point has been chosen for convenience, it being understood that the operation of the artificial heart 80 is substantially continuous.

[0089] The next operating cycle is initiated when the shuttle 110 is rotated in a counterclockwise direction indicated by arrow 89, causing the artificial heart 80 to assume the position shown in Figures 12A-12C. It is important to note that the rotation of the shuttle 110 has aligned the blood flow channels 121 and 122 with the output 84 and input 81, respectively. It is also important to note that this rotational position of the shuttle 110 has closed off the input 82 and output 83 (best seen in Figure 13B). Once the shuttle 110 is rotated, linear motion of the shuttle 110 to the left, indicated by arrow 97, is initiated by actuating the linear motion coils of the artificial heart 80 (seen in Figure 9) to move the shuttle 110 to the left, assuming the position shown in Figures 13A-13C.

[0090] 13A-13C illustrate the position of the artificial heart 80 as the shuttle 110 moves to the left. The shuttle 110 continues to be rotationally positioned such that the blood flow channels 121 and 122 are aligned with the output 84 and input 81, respectively, and the input 82 and output 83 are closed. With particular attention to FIG. 13C, the movement of the shuttle 110 in the direction indicated by arrow 97 displaces the blood volume in the cylinder head 127, causing it to flow outwardly through the blood flow channel 121 and the output 84 in the direction indicated by arrow 98. At the same time, the movement of the shuttle 110 to the left in the direction indicated by arrow 97 also increases the volume of the cylinder head 128. This increased volume then draws blood through the input 81 and the blood flow channel 122 filling the cylinder head 128. This simultaneous displacement of blood volume from the cylinder head 127 and the refilling of the other blood volume in the cylinder head 128 is a result of the double-acting nature of the pumping action of the artificial heart 80. Movement of the shuttle 110 to the left continues until the shuttle 110 reaches the end 125 of the cylinder 85, at which point the artificial heart 80 assumes the position shown in Figures 14A-14C.

[0091] Figures 14A-14C show the point in the operating cycle of the artificial heart 80 when the shuttle 110 reaches its leftmost position relative to the end 127 of the cylinder 85. At this point, the cylinder head 127 is at a minimum, while the cylinder head 128 holds a maximum amount of blood. The operating cycle of the artificial heart 80 continues as the shuttle 110 rotates clockwise in the direction indicated by the arrow 109, to the position shown in Figures 15A-15C.

[0092] Figures 15A-15C show the point in the operating cycle of the artificial heart 80 where the shuttle 110 has reached its maximum left position and has been rotated in the direction indicated by arrow 109 to the position shown in Figure 15A. It is important to note that the rotational position of the shuttle 110 now aligns the blood flow channels 121 and 122 with the inputs 82 and outputs 83, respectively, while the inputs 81 and outputs 84 are closed. The operating cycle of the artificial heart 80 continues as the linear motion coil (seen in Figure 9) is again energized causing the shuttle 110 to move to the right in the direction indicated by arrow 107. As the shuttle 110 moves in the direction indicated by arrow 107, the artificial heart 80 moves to the position shown in Figures 16A-16C.

[0093] 16A-16C reveal the operating cycle of the artificial heart 80 as the shuttle 110 continues to move in the direction indicated by arrow 107. When the blood flow channel 121 is aligned with the input 82, this movement increases the capacity of the cylinder head 127 to draw blood through the input 82 and the blood flow channel 121 in the direction indicated by arrow 132, filling the cylinder head 127. At the same time, this movement of the shuttle 110 and the alignment of the blood flow channel 122 during this movement displaces the blood volume within the cylinder head 128, causing blood to flow outwardly through the blood flow channel 122 and the output 83 in the direction indicated by arrow 131. Note that the rotational position of the shuttle 110, as best seen in FIG. 16C, maintains the input 81 and output 84 in a closed state. Blood flow continues in the direction of arrows 132 and 131 as shuttle 110 continues to move in the direction indicated by arrow 107 until shuttle 110 reaches end 126 of cylinder 85 and artificial heart 80 assumes the position shown in Figures 17A-17C.

[0094] Figures 17A-17C reveal the end point of the described operating cycle of the artificial heart 80 when the shuttle 110 reaches its rightmost position. At this position, the cylinder head 127 holds the maximum blood volume, while the cylinder head 128 holds the minimum blood volume. It will be appreciated that the position of the artificial heart 80 shown in Figures 17A-17C corresponds to the position shown in Figures 11A-11C. Thus, the artificial heart 80 has completed its operating cycle and returned to the selected starting point utilized in the preceding description and drawings. Operation of the artificial heart 80 continues as the above described sequence is repeated.

[0095] It will be understood that the above described operations of the artificial heart 80 are the same operations produced by the artificial heart 130. Accordingly, it will be understood that the descriptions and illustrations set forth above for the artificial heart 80 apply with equal force to the artificial heart 130.

[0096] Fig. 18 reveals a functional diagram showing the heart prosthesis 80 positioned in relation to a depiction of an exemplary human heart and lungs. It will be understood that Fig. 18 is merely representative of this cooperation and is not a detailed depiction of the individual connections utilized when the heart prosthesis 80 is implanted. In addition, it will be further understood that the diagram shown in Fig. 18 is equally representative of the use of the heart prosthesis 130.

[0097] FIG. 19 reveals a further alternative embodiment, generally referenced by the numeral 180, in which an external valve is utilized to provide the reversal of flow necessary to accommodate the reciprocating motion of a shuttle within the pump. The pump 180 utilizes a cylinder 181 having a set of linear motor coils 183 wound on its exterior surface. Within a bore 179, a shuttle 182 supporting a number of permanent magnets is linearly movable in the directions indicated by arrows 188 and 189. A pair of connecting tubes 191 and 192 extend from opposite ends of the cylinder 181 and are connected to a four-way valve 190. The four-way valve 190 includes a pair of connecting passages 193 and 194 that may be positioned as indicated by the solid line depiction or alternatively switched to alternative positions as indicated by dashed connections 195 and 196. An output of the four-way valve 190 is connected to an output 185 intended to allow material to flow in the direction indicated by arrow 187. The input of the four-way valve 190 is connected to an input pipe 184 designed to allow material to flow in the direction indicated by arrow 186 .

[0098] In operation, with the four-way valve 190 positioned according to the solid line connections 193 and 194 shown, the linear motor coil 183 is energized to drive the shuttle 182 in the direction indicated by arrow 188. This movement of the shuttle 182 displaces material within the volume 177, causing the material to flow outwardly from the cylinder 181 through passage 193 to the four-way valve 190 and outwardly in the direction indicated by arrow 187 through connection 185. At the same time, the movement of the shuttle 182 in the direction indicated by arrow 188 draws material inwardly into the trapped volume within volume 178. This flow draws material through the input 192 and connection 194 of the four-way valve 190. This in turn draws material through the connecting tube 184 in the direction indicated by arrow 86.

[0099] When shuttle 182 reaches the end of its travel in the direction indicated by arrow 188, the excitation of coil 183 is reversed to drive shuttle 182 in the direction indicated by arrow 189. At the same time, four-way valve 190 is switched to the position indicated as dashed connections 195 and 196. When shuttle 182 moves in the direction indicated by arrow 189, it displaces the material volume in volume 178 and drives it outward through connection 192. The flow of material through connection 182 is transmitted to output 185 by dashed four-way valve connection 196, causing an outward flow in the direction indicated by arrow 187. In addition, the movement of shuttle 182 in the direction indicated by arrow 189 draws material into volume 177 through connection 191. Dashed connection 195 of four-way valve 190 connects connection 191 to input 184, allowing material to be drawn in the direction indicated by arrow 186. This action continues as the shuttle 182 reciprocates within the cylinder bore 179 and the four-way valve 190 switches synchronously therewith.

[0100] method Use a ventricular assist device to pump blood Also described herein is a method of pumping blood into a recipient. The method generally includes linearly reciprocating a shuttle contained within a housing to simultaneously move blood into and out of the housing, the housing comprising a plurality of ports, and rotating the shuttle to selectively direct the movement of blood into and out of the plurality of ports. The shuttle generally reciprocates according to a pumping cycle that may be pre-set by a physician and then adjusted based on feedback regarding one or more detected parameters of the recipient. Such parameters may include indications such as heart rate or blood pressure, or symptoms such as shortness of breath or lightheadedness. The housing may be implanted within the recipient or may be external to the recipient with connections across the skin to reach the appropriate vasculature and / or heart chambers.

[0101] When the housing is implanted, a first port of the plurality of ports may be coupled to the recipient's aorta and a second port of the plurality of ports may be coupled to the recipient's left ventricle. This configuration of coupling may be useful when the device is a ventricular assist device.

[0102] In one embodiment, the ventricular assist device acts to pump or fill with blood with each shuttle stroke or reciprocation (single stroke reciprocation). Here, a single channel of the shuttle can be aligned with a first port, which is an input port, resulting in occlusion of a second port, which is an output port. The linear motion of the shuttle then moves blood from the left ventricle through the input port and into the housing. After the shuttle completes its stroke, it is then rotated to align the channel with the output port, closing the input port. The linear motion of the shuttle then moves blood from the housing through the output port and into the aorta, completing the pumping cycle. The cycle is then repeated to assist blood circulation in the recipient.

[0103] For example, with reference to Figures 2A-2C and 3A-3C, the ventricular assist device 10 is shown at the beginning of a pump cycle, which begins when the shuttle 26 rotates to align the channel 27 with the input 14. As a result, the output 15 is simultaneously blocked by this rotational position of the shuttle 26.

[0104] 2B, the shuttle 26 is shown at the beginning of a pump cycle with the shuttle 26 in its left position with the face 36 of the shuttle 26 proximate the end 34 of the cylinder 24. At this point, the volume of the cylinder head 28 is at a minimum, approximately zero. The pump stroke begins as the shuttle 26 is driven right, in the direction indicated by arrow 29, toward the end 35 of the cylinder 24. The movement of the shuttle 26 in the direction indicated by arrow 29 increases the volume within the cylinder head 28, which in turn draws blood from the input 14 into the channel 27, in the direction indicated by arrow 30. As the movement of the shuttle continues in the direction indicated by arrow 29, the volume of the cylinder head 28 further increases drawing additional blood into the cylinder head 28, filling the cylinder head 28 with blood until the shuttle 26 reaches its rightmost position shown in FIG. 2C.

[0105] Additionally, Figure 2C shows the ventricular assist device 10 at a point where the shuttle 26 has moved fully to the right, with face 37 of the shuttle 26 facing against end 35 of cylinder 24. At this point, a maximum amount of blood is trapped within cylinder head 28. The shuttle 26 is then rotated from the position shown in Figure 2A to the position shown in Figure 3A.

[0106] Figure 3A reveals a cross-sectional view of ventricular assist device 10 taken along section line 2A, 3A-2A, 3A in Figure 1. Figure 3A reveals ventricular assist device 10 at a midpoint of the pump cycle, where shuttle 26 has rotated to align channel 27 with output 15. As a result, output 15 is aligned with channel 27 of shuttle 26, and input 14 is simultaneously blocked by this rotated position of shuttle 26.

[0107] FIG. 3B shows the shuttle 26 in its correct position with face 36 of the shuttle 26 furthest from end 34 of cylinder 24. At this point, the volume of the cylinder head 28 is at its maximum. The pump stroke continues as the shuttle 26 is driven leftward, in the direction indicated by arrow 32, toward end 34 of cylinder 24. Movement of the shuttle 26 in the direction indicated by arrow 32 displaces the volume within the cylinder head 28, which then drives blood outwardly, in the direction indicated by arrow 33, into channel 27 and through output 15. As movement of the shuttle continues in the direction indicated by arrow 32, the blood volume within the cylinder head 28 is further displaced, forcing additional blood out of the cylinder head 28 until the shuttle 26 reaches its leftmost position shown in FIG. 3C.

[0108] Figure 3C shows the ventricular assist device 10 with the shuttle 26 moved fully to the left, at the point where the face 36 of the shuttle 26 faces against the end 34 of the cylinder 24. At this point, the blood volume trapped within the cylinder head 28 has been displaced outward through the output 15. The shuttle 26 is then rotated from the position shown in Figure 3A back to the position shown in Figure 2A, at which point the pump cycle is complete and repeated in the sequence depicted above.

[0109] The sequence of operations described above may be carried forward on a repetitive basis as the ventricular assist device 10 executes to provide a simple, easy to manufacture ventricular assist device utilizing a single action pumping action. This pumping action may be carried forward as the blood flow channel 27 rotates into alignment with the input 14 (arrow 29) each time the shuttle 26 moves to the right and rotates into alignment with the output 15 (arrow 32) each time the shuttle 26 moves to the left. The cylinder head 28 fills with a blood volume each time the shuttle 26 moves to the right and then a blood volume is displaced through the output 15 each time the shuttle 26 moves to the left.

[0110] In another embodiment, the ventricular assist device acts to pump and fill with blood with each shuttle stroke or reciprocation (double-acting reciprocating motion). In this embodiment, the shuttle includes three channels. The linear and rotational motions of the shuttle that align the channels with the ports and allow fluid communication therethrough or allow shutoff of blood to the chambers (cylinder heads 65 and 66) are described in detail by reference to Figures 4A-4C and 5A-5C.

[0111] With momentary reference to Figures 8, 9 and 10, it will be seen that the ventricular assist device 50 is also driven in linear motion by a plurality of linear motor coils surrounding the cylinder along with permanent magnets disposed on the inner surface of the shuttle. In addition, it will be equally clear that rotation of the shuttle during operation described below is induced by either additional rotational drive coils also disposed on the cylinder, or alternatively by a cooperating set of permanent magnets disposed on the shuttle and end caps of the cylinder. In any event, it will be understood that the following description assumes that such a system is in operation and that its functions are performed in the manner described below.

[0112] Returning to and simultaneously referring to FIGS. 4A-4C and 5A-5C, the ventricular assist device 50 includes a cylinder 51 defining a cylinder bore 52 therethrough. The cylinder 51 further defines closed ends 58 and 59. The cylinder 51 also supports an input coupler 53 and an output coupler 54, both of which are in communication with an inner surface of the cylinder bore 52. The shuttle 55 is generally cylindrical and is precisely mounted within the cylinder bore 52 so as to be freely movable therein. The shuttle 55 further defines a face 56 and a face 57. The cylinder head 65 comprises a volume within the cylinder bore 52 enclosed by the closed end 58 and face 56 of the shuttle 55 together with a portion of the cylinder bore 52 therebetween. The second cylinder head 66 comprises a volume within the cylinder bore 52 enclosed by the closed end 59 and face 57 of the shuttle 55 together with a portion of the cylinder bore 52 therebetween. Shuttle 26 also defines a number of blood flow channels 60, 61 and 62. Blood flow channel 60 is open at face 57 and closed at face 56. Blood flow channel 61 is closed at face 57 and open at face 56 of shuttle 55. Finally, blood flow channel 62 is open at face 57 and closed at face 56.

[0113] In operation, FIG. 4A reveals a cross-sectional view of the ventricular assist device 50. FIG. 4A reveals the ventricular assist device 50 at the beginning of a pump cycle, which is selected to correspond to a pump stroke that begins when the shuttle 55 is in its left position within the cylinder 51 and the shuttle 55 rotates to align the blood flow channel 61 with the input 53 and align the blood flow channel 60 with the output 54. As a result, the blood flow channel 62 is simultaneously blocked by this rotational position of the shuttle 55. The particular point in the operating cycle of the ventricular assist device 50 selected as the initial point for starting the exemplary pump cycle has been chosen for convenience. Any point in the operating cycle of the ventricular assist device 50 can also serve as a starting point for describing the pump cycle.

[0114] 4B shows the shuttle 55 at the start of an exemplary pump cycle with the shuttle 55 in its left position, with the face 56 of the shuttle 55 proximate the end 58 of the cylinder 51. At this point, the volume of the cylinder head 65 is at a minimum, near zero. At the same time, the left side and position of the shuttle 55 distances the face 57 of the shuttle 55 from the end 59 of the cylinder 51. As a result, the cylinder head 66 defines a maximum volume.

[0115] It should be noted that in accordance with the double-acting nature of the ventricular assist device 50, the volumes of the cylinder head volumes 65 and 66 on either side of the shuttle 55 change in opposite directions as the shuttle 55 moves within the cylinder bore 52. At the same time, as the shuttle 55 moves, one cylinder head increases in volume while the other decreases in volume. The proper direction of blood flow into and out of the cylinder heads is directed by aligning the appropriate blood flow channels with the input and output ports as the shuttle 55 rotates between each left-to-right and right-to-left linear motion of the shuttle 55. This facilitates the double-acting operation of the ventricular assist device 50, as each stroke of the shuttle 55 simultaneously draws a volume of blood into the opposite cylinder head through the input port while simultaneously displacing a volume of blood in one cylinder head through the output port.

[0116] A pump stroke begins as shuttle 55 is driven to the right in the direction indicated by arrow 63 toward end 59 of cylinder 51. Movement of shuttle 55 in the direction indicated by arrow 63 increases the volume within cylinder head 65, which then draws blood from input 53 into channel 61 in the direction indicated by arrow 67. As movement of shuttle 55 continues in the direction indicated by arrow 63, the volume of cylinder head 65 further increases drawing additional blood into cylinder head 65, filling cylinder head 65 with blood until shuttle 55 reaches its rightmost position shown in FIG. 4C. At the same time, as shuttle 55 is driven to the right in the direction indicated by arrow 63 toward end 59 of cylinder 51, movement of shuttle 55 displaces volume within cylinder head 66, which then forces blood to flow through channel 60 in the direction indicated by arrow 64. As movement of the shuttle continues in the direction indicated by arrow 63 , the volume of cylinder head 66 is further displaced, causing continued blood flow through output 54 in the direction indicated by arrow 64 .

[0117] Figure 4C shows ventricular assist device 50 at the point where shuttle 55 has moved fully to the right, with face 57 of shuttle 55 facing against end 59 of cylinder 51. At this point, the maximum amount of blood is trapped in cylinder head 65 and the minimum amount of blood is trapped in cylinder head 66. Shuttle 55 is then rotated from the position shown in Figure 4A to the position shown in Figure 5A.

[0118] 5A reveals a cross-sectional view of ventricular assist device 50 at the midpoint of a pump cycle where shuttle 55 has rotated in the direction indicated by arrow 70 to align channel 61 with output 54 and blood flow channel 62 with input 53. As a result, output 54 is aligned with channel 61 of shuttle 55, while blood flow channel 62 is aligned with input 53. Blood flow channel 60 is simultaneously blocked by this rotational position of shuttle 55.

[0119] 5B shows shuttle 55 in its correct position with face 56 of shuttle 55 furthest from end 58 of cylinder 51 and face 57 closest to end 59 of cylinder 51. At this point, the volume of cylinder head 65 is at a maximum, while the volume of cylinder head 66 is at a minimum. The pump stroke continues as shuttle 55 is driven leftward, in the direction indicated by arrow 71, toward end 58 of cylinder 51. Movement of shuttle 55 in the direction indicated by arrow 71 displaces volume within cylinder head 65, which in turn drives blood into channel 61 and outward through output 54, in the direction indicated by arrow 72. This movement of shuttle 55 also increases the volume of cylinder head 66, drawing blood through input 53 and into channel 62, in the direction indicated by arrow 73. As movement of the shuttle leftward in the direction indicated by arrow 71 continues, the blood volume within cylinder head 65 is further displaced, forcing additional blood out of cylinder head 65 while blood continues to be drawn into channel 62 filling cylinder head 66 until shuttle 55 reaches its leftmost position shown in FIG. 5C.

[0120] Figure 5C shows the ventricular assist device 50 with the shuttle 55 moved fully to the left, at the point where the face 56 of the shuttle 55 faces against the end 58 of the cylinder 51. At this point, the blood volume trapped within the cylinder head 65 has been displaced outward through the output 54, and a new blood volume is trapped within the cylinder head 66. The shuttle 55 is then rotated from the position shown in Figure 5A back to the position shown in Figure 4A, at which point the pump cycle is complete and repeated in the sequence depicted above.

[0121] Thus, the sequence of operations described above is carried forward on an iterative basis as the ventricular assist device 50 performs to provide a compact, highly efficient ventricular assist device utilizing a double-acting pumping action. This pumping action is carried forward as the blood flow channel 61 rotates to align with the input 53 and the blood flow channel 60 rotates to align with the output 54 (arrow 63) each time the shuttle 55 moves to the right, whereas the blood flow channel 61 rotates to align with the output 54 and the blood flow channel 62 rotates to align with the input 53 (arrow 71) each time the shuttle 55 moves to the left. The cylinder head 65 fills with a blood volume and the blood volume in the cylinder head 66 is displaced each time the shuttle 55 moves to the right. Conversely, the cylinder head 66 fills with a blood volume and the blood volume in the cylinder head 65 is displaced each time the shuttle 55 moves to the left.

[0122] Generally, the movement of blood into the shuttle can be simultaneous with the movement of blood from the shuttle. This movement of blood can be generated by a pumping cycle that can match the recipient's sinus rhythm when the ventricular assist device is employed, and then adjusted as needed if blood pressure needs to be increased or decreased, or if another parameter (e.g., oxygen level or dissolved carbon dioxide level) indicates that an adjustment is necessary. The parameters can be detected, for example, using electrodes attached to the recipient's native heart that receive signals from the recipient's native heart or brain (e.g., via the sinoatrial node), which are then used to adjust the pumping cycle of the ventricular assist device. Adjustments can include activating the ventricular assist device to pump when the native heart is at rest or in diastole, or pumping at a particular stage of the cardiac cycle.

[0123] Use an artificial heart to pump blood When the housing is part of an artificial heart, implanting may include connecting a first port of the plurality of ports to the recipient's aorta, connecting a second port of the plurality of ports to the recipient's pulmonary artery, connecting a third port of the plurality of ports to the recipient's inferior vena cava and superior vena cava, and connecting a fourth port of the plurality of ports to the recipient's pulmonary vein.

[0124] Generally, the movement of blood into the shuttle is simultaneous with the movement of blood from the shuttle. This movement of blood is generated by pumping cycles that are predetermined based on parameters set by the physician and can be adjusted as needed if blood pressure needs to be increased or decreased. In some embodiments, the speed of the pumping cycles (or other cycle parameters) can be adjusted automatically based on the recipient's blood pressure. For example, the controller can automatically adjust the speed of the pumping cycles based on feedback from a pressure sensor associated with the pumping device. Alternatively or additionally, the speed of the pumping cycles can be adjusted manually by the recipient or physician. In addition to maintaining or changing blood pressure, the artificial heart can respond to oxygen levels in the blood through the use of a blood oximeter or pulse oximeter, or through the measurement of dissolved carbon dioxide with a carbon dioxide sensor.

[0125] Additionally, described herein are methods for treating heart failure. The methods generally include implanting a housing in a recipient. The housing may include a shuttle that reciprocates linearly to simultaneously move blood into and out of the housing. Additionally, the shuttle may be rotated to direct the flow of blood into and out of the housing. The linear reciprocation and rotation of the shuttle typically creates a pumping cycle.

[0126] Heart failure may be treated by implanting either a ventricular assist device or an artificial heart. In the same manner as above, the speed of the pumping cycle (or other cycle parameters) may be automatically adjusted based on the blood pressure of the recipient. For example, the controller may automatically adjust the speed of the pumping cycle based on feedback from a pressure sensor associated with the pumping device. Alternatively or additionally, the speed of the pumping cycle may be manually adjusted by the recipient or a physician. Types of heart failure that may be treated include left-sided heart failure, right-sided heart failure, biventricular heart failure, cardiomyopathy, or heart failure due to infection.

[0127] In the foregoing description, for purposes of explanation, specific nomenclature was used to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required to practice the present invention. Thus, the foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously, many modifications and variations are possible in light of the above teachings. The embodiments have been selected and described in order to explain the principles of the invention and its practical application, thereby enabling those skilled in the art to utilize the present invention and its various embodiments with various modifications as suited to the particular use contemplated.

Claims

1. 1. A device for pumping blood, comprising: a cylindrical housing having an exterior surface, a plurality of ports, a first end and a second end, the first end and the second end defining a chamber between the first end and the second end; a shuttle within the chamber, the shuttle comprising an outer sleeve defining a hollow interior surface containing a plurality of magnets and one or more channels extending longitudinally along the outer sleeve; a clearance gap between the housing and the shuttle sized to prevent the passage of red blood cells; a magnetic actuation system operable to impart linear and rotational motion to said shuttle; Equipped with The device, wherein the linear motion of the shuttle pumps blood into and out of the chamber according to a pumping cycle, and the rotational motion of the shuttle selectively directs flow of blood through the plurality of ports.

2. 10. The device of claim 1, wherein the housing, or the shuttle, or both the housing and the shuttle, comprise a ceramic material, the ceramic material comprising sapphire or a synthetic variant thereof, or zirconia or a synthetic variant thereof.

3. The device of claim 1, further comprising a manifold.

4. 4. The device of claim 3, wherein the manifold includes a first inlet, a second inlet, a first outlet, and a second outlet, the first inlet and the second inlet and the first outlet and the second outlet being in fluid communication with corresponding ones of the plurality of ports.

5. The device of claim 3 , wherein the manifold includes a single inlet and a single outlet, both of the single inlet and the single outlet being in fluid communication with corresponding ones of the plurality of ports.

6. The device of claim 1 , wherein the clearance gap is from about 2.0 μm to about 4.0 μm.

7. The device of claim 1 , wherein the one or more channels have one open end and one closed end.

8. 10. The device of claim 1, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a plurality of rotating coils disposed at the first and second ends of the cylindrical housing.

9. 10. The device of claim 1, wherein the magnetic actuation system comprises a plurality of linear motor coils surrounding the cylindrical housing and a permanent magnet disposed within each of the first and second ends of the cylindrical housing.

10. The device of claim 1 , wherein the device includes a controller operably coupled to the magnetic actuation system, the controller configured to control the pumping cycle.

11. The device of claim 10 , wherein the controller is operatively connected to a pressure sensor.

12. The device of claim 10 , wherein the controller is configured to wirelessly transmit information from the device to an external device.

13. The device of claim 1, further comprising a coating on an outer surface of the housing.

14. The device of claim 1 , wherein the device is an artificial heart.

15. The device described in claim 11, wherein the controller is configured to adjust the pumping cycle based on blood pressure data received from the pressure sensor.

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