Totally implantable artificial replacement heart

• US 3,919,722 A
• Filed: 03/06/1973
• Issued: 11/18/1975
• Est. Priority Date: 03/06/1973
• Status: Expired due to Term

• Current Assignee: Lowell T. Harmison
• Original Assignee: Lowell T. Harmison
• Inventors: Harmison, Lowell T.
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US05/338,611
• Time in Patent Office: 987 Days
• Field of Search: 3/1,DIG.2,1.7 128/1D,DIG.3
• US Class Current: 623/3.16
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/8243 by induction
• 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 60/268 the displacement member being flexible, e.g. membranes, diaphragms or bladders
• CPC Class Codes: A61M 60/424 for positive displacement blood pumps
• CPC Class Codes: A61M 60/443 with means converting the rotation into a translational movement of the displacement member
• CPC Class Codes: A61M 60/515 Regulation using real-time patient data
• CPC Class Codes: A61M 60/538 Regulation using real-time blood pump operational parameter data, e.g. motor current
• CPC Class Codes: A61M 60/859 Connections therefor
• CPC Class Codes: A61M 60/873 specially adapted for wireless or transcutaneous energy transfer [TET], e.g. inductive charging
• CPC Class Codes: A61M 60/876 Implantable batteries
• CPC Class Codes: A61M 60/89 Valves
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F02G 1/043 the engine being operated by expansion and contraction of a mass of working gas which is heated and cooled in one of a plurality of constantly communicating expansible chambers, e.g. Stirling cycle type engines
• CPC Class Codes: F02G 2280/005 Medical applications, e.g. for prosthesis or artificial hearts

Abstract

A totally implantable replacement heart system comprises a blood pump, energy converter, heart rate control computer and an energy storage unit. The blood pump is a four-chambered unit having two reservoirs or atria with two large valves forming the inflow to the pumping chambers or ventricles, and tricuspid pulmonary and aortic valves. The artificial heart has been designed to adapt to different types of internal power systems (electrical, nuclear, or pneumatic). The heart rate control computer utilizes stroke volume as one of the principal control parameters. This control system is always seeking to converge on a rate that maintains stroke volume at full value or at a predetermined high percent of full stroke volume. A key part of the control logic is the automatic override of heart rate from the right heart thereby providing sensitivity to central venous conditions.

Claims

1. A totally implantable replacement heart comprising:

a blood pumping means for pumping blood to and receiving blood from the lungs, and pumping blood to the venous system and receiving blood from the arterial system;

pump drive means for periodically activating said pumping means at a specific activation rate;

heart rate sensing means for detecting the physiological demand of the body for a supply of blood thereto and for providing an output signal in response to the physiological demand, said sensing means including detection means associated with said pumping means for sensing when a predetermined volume has been pumped by said pumping means during any activation thereof; and

heart rate control means, connected to said means for periodically activating said pumping means and said sensing means, for contRolling the activation rate of said pumping means in response to said output of said sensing means, said control means including;

a computer means for continuously monitoring the activation rate of said pumping means and said output signal from said sensing means, and after every series of a predetermined number of activations of said pumping means generating an output signal to either increase, decrease or maintain the activation rate.

2. A totally implantable replacement heart of claim 1, wherein said pump drive means includes a power source to be totally implanted within the body of the recipient of the replacement heart.

3. A totally implantable replacement heart of claim 2, wherein said power source includes a heat engine containing a radioactive isotope heat source.

4. A totally implantable replacement heart of claim 2, wherein said power source includes a rechargeable battery, electrically connected to a power transfer means to be implanted in the body of the recipient of the replacement heart for transferring electrical energy across intact layers of skin of the recipient.

5. The totally implantable replacement heart of claim 1, wherein all blood contacting surfaces are coated with an endothelial or pseudo-endothelial material to permit a living surface to develop.

6. A totally implantable replacement heart comprising:

pumping means for pumping blood consisting of;

first and second pumping chambers corresponding respectively to the left and right ventricles of a natural heart;

first and second reservoirs corresponding to the atria of a natural heart;

driving means for periodically compressing said first and second pumping chambers at a predetermined activation rate;

said first and second reservoirs each having a valve therein leading to a respective one of said pumping chambers;

each of said pumping chambers having a valve therein;

a heart rate sensing means for detecting the physiological demand of the body for a supply of blood thereto, and for providing an output signal in response to the physiological demand, said sensing means including first and second detection means, associated respectively with said first and second pumping chambers, for detecting the extent of filling of said first and second pumping chambers and providing an output signal each time one of said first and second pumping chambers is filled to a predetermined extent; and

, heart rate control means, connected to said driving means and said sensing means, for controlling the activation rate of said driving means in response to the output signals of said first and second detection means, said control means comprising a computer means, electrically connected to said driving means and said first and second detection means, for continuously monitoring the activation rate of said driving means and the output signals of said first and second detection means and after every series of a predetermined number of activations generating a control signal dependent upon the output signals of said first and second detection means to either increase, decrease or maintain the activation rate.

7. The totally implantable replacement heart of claim 6, wherein said computer means further includes:

first flow determining means for determining the number of times said first pumping chamber is filled to a predetermined extent during each said series of a predetermined number of activations, second flow determining means for determining the number of times said second pumping chamber is filled to a predetermined extent during each said series of a predetermined number of activations;

means for generating a control signal to increase the activation rate when either said first or said second pumping chambers is filled to said predetermined extent for at least a first specified percentage of activations during said series of activations;

means for generating a control signal to decrease the activation rate when said first pumping chambEr is filled to said predetermined extent for less than a second specified percentage of activations during said series of activations, and said second pumping chamber is filled to said predetermined extent for less than a third specified percentage of activations during said series of activations;

means for generating a control signal to maintain the activation rate without change when said first pumping chamber is filled to said predetermined extent for more than a fourth specified percentage but less than a fifth specified percentage of activations during said series of activations, and said second pumping chamber is filled to said predetermined extent for no more than a sixth specified percentage of activations during said series of activations; and

means for generating a signal to increase said activation rate when said first pumping chamber is filled to said predetermined extent for no more than a seventh specified percentage of activations during said series of activations and said second pumping chamber is filled to said predetermined extent during more than an eighth specified percentage, greater than said seventh specified percentage of activations during said series of activations.

8. A totally implantable replacement heart of claim 6, wherein said driving means includes a power source to be totally implanted within the body of the recipient of the replacement heart.

9. A totally implantable replacement heart of claim 8, wherein said power source includes a heat engine containing a radioactive isotope heat source.

10. A totally implantable replacement heart of claim 8, wherein said power source includes a rechargeable battery, electrically connected to a power transfer means to be implanted in the body of the recipient of the replacement heart for transferring electrical energy across intact layers of skin of the recipient of the replacement heart.

11. The totally implantable replacement heart of claim 6, wherein all blood contacting surfaces are coated with an endothelial or pseudo-endothelial material to permit a living surface to develop.

12. A totally implantable replacement heart comprising:

first and second A-V valve plates having first and second sides;

right and left atria, each consisting of a flexible cup-shaped bladder having an inlet valve at one end thereof and sealingly engaging said first and second A-V valve plates at the other end thereof, thereby forming, with said first side of respectively said first and second A-V valve plates, right and left atria chambers;

a right ventricle consisting of a first flexible bladder, said first bladder being closed at one end thereof and the other end thereof sealingly engaging said first A-V valve plate on said second side thereof;

a left ventricle consisting of a second flexible bladder, said second bladder being closed at one end thereof and the other end thereof sealingly engaging said second A-V valve plate on said second side thereof;

housing means for enclosing said right and left ventricles;

said right and left ventricles each having at least one outlet valve;

check valve means in said first and second A-V valve plates for allowing blood flow from respectively said right atria to said right ventricle and said left atria to said left ventricle, while preventing blood flow from respectively said right ventricle to said right atria and said left ventricle to said left atria, said check valve means comprising longitudinal openings in said first and second A-V valve plates and flexible flaps hingedly attached to said second sides of said A-V valve plates, overlaying said longitudinal openings, and having a shape substantially the same as said longitudinal openings, said flexible flaps being of slightly larger dimensions than said longitudinal openings; and

means contained within said housing means for compressing said first and second bladders.

13. A method of controlling pumping of an artificial heart having left and rIght ventricles and left and right atria comprising the steps of:

periodically compressing the left and right ventricles at a specific activation rate;

detecting the degree of left and right ventricle filling;

providing a first output signal each time the left ventricle receives a predetermined amount of blood;

providing a second output signal each time the right ventricle receives a predetermined amount of blood; and

controlling the activation rate by analyzing said first and second output signals during a period corresponding to a predetermined number of activations in order to vary the activation rate at the end of said period dependent upon the number of said first output signals and the number of said second output signals.