Total artificial heart

• US 5,300,111 A
• Filed: 02/03/1992
• Issued: 04/05/1994
• Est. Priority Date: 02/03/1992
• Status: Expired due to Fees

• Current Assignee: Pyxis Corp. (Cardinal Health, Inc.)
• Original Assignee: Pyxis Corp. (Cardinal Health, Inc.)
• Inventors: Panton, Ronald L., Healey, William V.
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): BURKE, ELIZABETH
• Application Number:
  US07/830,051
• Time in Patent Office: 792 Days
• Field of Search: 623/3, 600/16-18
• US Class Current: 623/3.19
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: A61M 60/196 replacing the entire heart, e.g. total artificial hearts [TAH]
• CPC Class Codes: A61M 60/462 Electromagnetic force
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood

Abstract

A totally implantable artificial heart with two ventricles is disclosed. The blood is pumped alternately from each ventricle using a linear electric motor that moves an armature to push the movable walls of the ventricles. The motor may be made small, and hence light, if it is electrically inefficient. Excess heat is transferred by the convective motion of a heat transfer fluid through special passages in the motor and by effective conduction paths designed into the elements. The motion of the heat transfer fluid is engendered by the movable walls that at the same time are performing the pumping action.

Claims

1. A totally implantable artificial heart comprising:

(a) a central housing;

(b) a linear electric motor enclosed within the central housing, comprising;

(i) a stationary stator;

(ii) an armature including a first armature end and a second armature end, the armature linearly movable along a longitudinal axis of the armature in response to an electric current provided to the motor, a linear operation of the electric motor producing thermal energy;

(c) a right ventricle cavity forming a selectively variable right ventricle cavity volume for receiving and expelling blood, the right ventricle cavity comprising;

(i) a right ventricle housing attached to the central housing;

(ii) a first movable wall comprising a first pusher plate attached to the central housing by a first flexible seal and attached to the first armature end such that a linear motion of the armature causes the right ventricle cavity volume to change;

(d) a first inlet port including a first inlet valve for allowing blood to enter the right ventricle cavity when the right ventricle cavity volume increases;

(e) a first outlet port including a first outlet valve for allowing blood to exit the right ventricle cavity when the right ventricle cavity volume decreases;

(f) a left ventricle cavity forming a selectively variable left ventricle cavity volume for receiving and expelling blood, the left ventricle cavity comprising;

(i) a left ventricle housing attached to the central housing;

(ii) a second movable wall comprising a second pusher plate attached to the central housing by a second flexible seal and attached to the second armature end such that the linear motion of the armature causes the left ventricle cavity volume to change;

(g) a second inlet port including a second inlet valve for allowing blood to enter the left ventricle cavity when the left ventricle cavity volume increases;

(h) a second outlet port including a second outlet valve for allowing blood to exit the left ventricle cavity when the left ventricle cavity volume decreases; and

(i) heat transfer means for simultaneously conducting thermal energy from the electric motor to the first and second pusher plates, to the left and right ventricle housings, to the central housing, to blood that is being pumped through the artificial heart, and to body tissues surrounding the artificial heart.

2. The totally implantable artificial heart of claim 1 wherein the heat transfer means includes:

(a) at least one flow passage selected from the group consisting of a flow passage over the stator, a flow passage through the stator, a flow passage through the armature, and a flow passage between the stator and the armature;

(b) a heat transfer fluid; and

(c) a plurality of heat transfer reservoir means for supplying heat transfer fluid to and receiving heat transfer fluid from at least one flow passage, the linear motion of the armature causing the heat transfer fluid to flow.

3. The totally implantable artificial heart of claim 2 wherein the at least one flow passage includes enhanced heat transfer surfaces.

4. The totally implantable artificial heart of claim 2 further comprising an impeller attached to the armature such that the linear motion of the armature sets the impeller in motion causing the heat transfer fluid to flow.

5. The totally implantable artificial heart of claim 1 wherein the heat transfer means further includes at least one heat conduction path selected from the group consisting of a heat conduction path through the armature, a heat conduction path through the first and second pusher plates, a heat conduction path from the stator to the right and left ventricle housings, and a heat conduction path from the stator to the central housing.

6. A totally implantable artificial heart comprising:

(a) a central housing;

(b) a linear electric motor enclosed within the central housing, comprising;

(i) a stationary stator;

(ii) an armature including an armature end, the armature linearly movable along a longitudinal axis of the armature in response to an electric current provided to the motor, an operation of the electric motor producing thermal energy;

(c) a right ventricle cavity forming a selectively variable right ventricle cavity volume for receiving and expelling blood, the right ventricle cavity, comprising;

(i) a right ventricle housing attached to the central housing;

(ii) a first movable wall comprising a pusher plate attached to the central housing by a flexible seal and attached to the armature end such that a linear motion of the armature causes the first movable wall to move thereby causing the right ventricle cavity volume to change;

(d) a first inlet port including a first inlet valve for allowing blood to enter the right ventricle cavity when the right ventricle cavity volume increases;

(e) a first outlet port including a first outlet valve for allowing blood to exit the right ventricle cavity when the right ventricle cavity volume decreases;

(f) a left ventricle cavity forming a selectively variable left ventricle cavity volume for receiving and expelling blood, the left ventricle cavity comprising;

(i) a left ventricle housing attached to the central housing;

(ii) a second movable wall comprising a flexible diaphragm;

(g) a pressure transfer fluid for transferring pressure generated at the pusher plate to the flexible diaphragm, the pressure transfer fluid occupying a region formed by the pusher plate, the flexible seal, the central housing, and the flexible diaphragm, a motion of the pusher plate causing a motion of the diaphragm, resultantly causing the left ventricle cavity volume to change;

(h) a second inlet port including a second inlet valve for allowing blood to enter the left ventricle cavity when the left ventricle cavity volume increases;

(i) a second outlet port including a second outlet valve for allowing blood to exit the left ventricle cavity when the left ventricle cavity volume decreases; and

(j) heat transfer means which includes the pressure transfer fluid for simultaneously conducting thermal energy from the electric motor to the first and second movable walls, to the left and right ventricle housings, to the central housing, to blood that is being pumped through the artificial heart, and to body tissues surrounding the artificial heart.

7. The totally implantable artificial heart of claim 6 wherein the heat transfer means includes:

(a) at least one flow passage selected from the group consisting of a flow passage over the stator, a flow passage through the stator, a flow passage through the armature, and a flow passage between the stator and the armature;

(b) a heat transfer fluid; and

(c) a plurality of heat transfer reservoir means for supplying heat transfer fluid to and receiving heat transfer fluid from at least one flow passages, the linear motion of the armature causing the heat transfer fluid to flow.

8. The totally implantable artificial heart of claim 7 wherein the at least one flow passage includes enhanced heat transfer surfaces.

9. The totally implantable artificial heart of claim 7 further comprising an impeller attached to the armature such that the linear motion of the armature sets the impeller in motion causing the heat transfer fluid to flow.

10. The totally implantable artificial heart of claim 6 wherein the heat transfer means further includes at least one heat conduction path selected from the group consisting of a heat conduction path through the armature, a heat conduction path through the pusher plate, a heat conduction path from the stator to the right and left ventricle housings, and a heat conduction path from the stator to the central housing.

11. A totally implantable artificial heart comprising:

(a) a central housing;

(b) a linear electric motor enclosed within the central housing, comprising;

(i) a stationary stator;

(ii) an armature including an armature end, the armature linearly movable along a longitudinal axis of the armature in response to an electric current provided to the motor, an operation of the electric motor producing thermal energy;

(c) a right ventricle cavity forming a selectively variable right ventricle cavity volume for receiving and expelling blood, the right ventricle cavity, comprising;

(i) a right ventricle housing attached to the central housing;

(ii) a first movable wall comprising a first flexible diaphragm, a motion of the first movable wall causing the right ventricle cavity volume to change;

(d) a first inlet port including a first inlet valve for allowing blood to enter the right ventricle cavity when the right ventricle cavity volume increases;

(e) a first outlet port including a first outlet valve for allowing blood to exit the right ventricle cavity when the right ventricle cavity volume decreases;

(f) a left ventricle cavity forming a selectively variable left ventricle cavity volume for receiving and expelling blood, the left ventricle cavity comprising;

(i) a left ventricle housing attached to the central housing;

(ii) a second movable wall comprising a second flexible diaphragm, a motion of the second movable wall causing the left ventricle cavity volume to change;

(g) a second inlet port including a second inlet valve for allowing blood to enter the left ventricle cavity when the left ventricle cavity volume increases;

(h) a second outlet port including a second outlet valve for allowing blood to exit the left ventricle cavity when the left ventricle cavity volume decreases;

(i) a movable piston attached to the armature;

(j) a first pressure transfer fluid for transferring pressure generated by the movable piston to the first flexible diaphragm, the pressure transfer fluid occupying a first region formed by the movable piston, the first flexible diaphragm, and the central housing, a motion of the movable piston causing a motion of the first flexible diaphragm, resultantly causing the right ventricle cavity volume to change, the first pressure transfer fluid also facilitating the transfer of heat;

(k) a second pressure transfer fluid for transferring pressure generated by the movable piston to the second flexible diaphragm, the pressure transfer fluid occupying a second region formed by the movable piston, the second flexible diaphragm, and the central housing, a motion of the movable piston causing a motion of the second flexible diaphragm, resultantly causing the left ventricle cavity volume to change the second pressure transfer fluid also facilitating the transfer of heat; and

(1) heat transfer means for simultaneously conducting thermal energy from the electric motor to the first and second movable walls, to the left and right ventricle housings, to the central housing, to blood that is being pumped through the artificial heart, and to body tissues surrounding the artificial heart.

12. The totally implantable artificial heart of claim 11 wherein the heat transfer means includes:

(a) at least one flow passage selected from the group consisting of a flow passage over the stator, a flow passage through the stator, a flow passage through the armature, and a flow passage between the stator and the armature;

(b) a heat transfer fluid;

(c) a plurality of heat transfer reservoir means for supplying heat transfer fluid to and receiving heat transfer fluid from at least one flow passages, the linear motion of the armature causing the heat transfer fluid to flow.

13. The totally implantable artificial heart of claim 12 wherein the at least one flow passage includes enhanced heat transfer surfaces.

14. The totally implantable artificial heart of claim 12 further comprising an impeller attached to the armature, such that a linear motion of the armature sets the impeller in motion thereby causing the heat transfer fluid to flow.

15. The totally implantable artificial heart of claim 11 wherein the heat transfer means further includes at least one heat conduction path selected from the group consisting of a heat conduction path through the armature, a heat conduction path through the pusher plate, a heat conduction path from the stator to the right and left ventricle housings, and a heat conduction path from the stator to the central housing.