Implantable blood pump and integral apparatus for the operation thereof

• US 4,652,265 A
• Filed: 09/23/1982
• Issued: 03/24/1987
• Est. Priority Date: 09/23/1982
• Status: Expired due to Fees

• Current Assignee: David A. Mcdougall
• Original Assignee: David A. Mcdougall
• Inventors: McDougall, David A.
• Primary Examiner(s): FRINKS, RONALD
• Application Number:
  US06/422,295
• Time in Patent Office: 1,643 Days
• Field of Search: 3/1.7, 3/1-1.2, 3/1.9, 3/1.91, 128/1 D, 623/3, 623/11, 623/13, 623/14, 623/24-26
• US Class Current: 623/3.12
• 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 60/258 Piston pumps
• CPC Class Codes: A61M 60/427 the force acting on the blood contacting member being hydraulic or pneumatic
• CPC Class Codes: A61M 60/435 with diastole or systole switching by valve means located between the blood pump and the hydraulic or pneumatic energy source
• CPC Class Codes: A61M 60/531 using blood pressure data, e.g. from blood pressure sensors
• CPC Class Codes: A61M 60/861 Connections or anchorings for connecting or anchoring pumps or pumping devices to parts of the patient's body
• CPC Class Codes: A61M 60/882 Devices powered by the patient, e.g. skeletal muscle powered devices

Abstract

A blood pump is powered by an implantable motive power source. The blood pump has four actively pumping chambers, two of the chambers simulating ventricles and two of the chambers simulating atria, wherein the ventricular and atrial chambers are driven in a reciprocating manner by a pivoting wedge hinged to a septal wall partition separating the ventricular from the atrial chambers. The pivoting wedge is hydraulically powered through systole and diastole by means of hydraulic motors harnessed individually to respective skeletal muscles and responsive to the contraction of these muscles which are sequentially contracted by control stimulation means. The hydraulic pressure from the hydraulic motors is transmitted through hydraulic lines to the blood pump.

Claims

1. Apparatus for use in a heart replacement blood pump comprising a plurality of actively pumping chambers, each of the chambers including side walls and a reciprocating moving wall, an expandable sealed chamber in each pump chamber attached to side walls thereof and to the movable reciprocating wall and containing a hydraulic fluid forming a cushion, a blood sac in each pumping chamber having an open end attached to the side walls thereof and being fully supported towards and including its closed end by the cushion formed by the hydraulic fluid, the blood sac being somewhat conical when in a collapsed position and hemi-ellipsoidal shape when in an extended position, the blood sac being molded in a corrugated pattern consisting of elongated corrugations extending in its longitudinal direction and annular corrugations extending circumferentially of the sac, such that the sac can expand circumferentially and longitudinally when drawn by the cushion acting on the sac under the influence of negative pressure to expand the sac and thus causing blood to enter the sac.

2. An artificial replacement muscle in combination with an implatable motive power apparatus, comprising means for harnessing the contractile force of one or more skeletal muscles while the skeletal muscles remain in their anatomic position, and means for transmitting the motive power from said means for harnessing to the artificial replacement muscle for operating the artificial muscle in a manner simulating the operation of the muscle it is replacing, wherein the means for harnessing a skeleltal muscle includes a linear displacement hydraulic motor having anchor plates at each end thereof respectively adapted to be connected to the tendon material at each end of the muscle, and hydraulic fluid displacement means associated with the motor for displacing hydraulic fluid when the skeletal muscle contracts, wherein the artificial replacement muscle is a heart pump and the harness means are individually adapted to be attached to a plurality of skeletal muscles and the respective insertion tendons of said skeletal muscles are severed, and the natural motor nerves of the skeletal muscles are sugically interrupted, and the anchor plates of said harness means are adapted to be connected to each end of the respective muscle, and artificial stimulation means are provided such that the harnessed muscles will contract in sequence, wherein a systolic-diastolic actuator is provided and is implantable within the body, and said hydraulic conduit extends from each hydraulic motor means to one end of the systolic-diastolic actuator and a single conduit means extends from the systolic-diastolic actuator to the blood pump, each pulse of hydraulic pressure from the hydraulic motor means adapted to be attached to said skeletal muscles in response to said sequential contraction of said muscles causing the systolic-diastolic actuator to transmit through said single hydraulic line hydraulic pressure to the heart pump to power corresponding systolic strokes of the blood pump, wherein the systolic-diastolic actuator includes a housing defining a central bore passing through the housing, an inlet at one end of the housing communicating with the bore and an outlet at the other end of the housing communicating with the bore, a plunger being slidable within the bore and a sealed expandable chamber being provided within the bore communicating with the inlet and abutting the plunger, a sealed expandable chamber provided in the bore communicating with the outlet, and hydraulic fluid conduits from the varius hydraulic bores communicating with the inlet of the bore, whereby when hydraulic fluid from one of said hydraulic motors is displaced upon contraction of a muscle, the fluid pressure in the hydraulic conduits will expand the sealed chamber within the bore communicating with the inlet, thereby moving the plunger towards the outlet and thereby displacing the hydraulic fluid to the heart pump to effect the systolic stroke, and means for returning the plunger to its initial position during diastole;

a parallel satellite bore extending adjacent the said bore and the plunger has an extension which extends laterally into the satellite bore, an inlet port provided on the housing communicating with the satellite bore but adjacent and on the same side as the outlet of the central bore, an expandable sealed chamber provided in the satellite bore communicating with the inlet and contacting the extension of the plunger, harness means and a hydraulic conduit communicating with the inlet port of the satellite bore such that when the muscle to which the latter harness means is attached is stimulated, it will dispace hydraulic fluid through the hydraulic conduit into the satellite bore through the inlet port thereby efflectively hastening diastolic stroke when necessary;

electrical sensor members provided in the housing, and electrical contact means on said plunger adapted to slide against said sensor members in order to electronically sense the position of the plunger within the systolic-diastolic actuator.

3. An apparatus as defined in claim 2 wherein a reservoir for hydraulic fluid is provided in the conduits between the plurality of hydraulic motors, and the inlet port to the central bore of the systolic-diastolic actuator means such that hydraulic fluid can be displaced into the reservoir and the hydraulic pressure can be stored in response to the contraction of the respective muscles and the displacement of the fluid towards the reservoir, and valve means for providing a regualted pulse of hydraulic pressure to the systolic-diastolic actuator means;

the reservoir including a chamber adapted to receive the hydraulic fluid and having an elastic membrane separating the chamber between a gas filled sub-chamber and a hydraulic fluid sub-chamber, said valve means including a solenoid operated valve controlled by control means for opening and closing the valve to allow fluid from the hydraulic fluid sub-chamber to the inlet of the central bore in the systolic-diastolic actuator means and a position whereby communication between the hydraulic fluid sub-reservoir and the inlet is blocked off and the return from the inlet is passed through a return reservoir during diastole.

4. An apparatus as defined in claim 2 wherein spring means are fixed at one end to the housing and at the other end to the plunger so as to return the plunger during diastole to its end-diastolic position forcing the hydraulic fluid from the expandable chamber to return to the hydraulic motor means, thereby extending the respective muscles to their relaxed position.

5. An artificial replacement muscle in combination with an implantable motive power apparatus, comprising means for harnessing the contractile force of one or more skeletal muscles while the skeletal muscles remain in their anatomic position, and means for transmitting the motive power from said means for harnessing to the artificial replacement muscle for operating the artificial muscle in a manner simulating the operation of the muscle it is replacing, wherein the means for harnessing a skeletal muscle includes a linear displacement hydraulic motor having anchor plates at each end thereof respectively adapted to be connected to the tendon material at each end of the muscle, and hydraulic fluid displacement means associated with the motor for displacing hydraulic fluid when the skeletal muscle contracts, wherein the hydraulic motor includes a pair of elongated sealed expandable chambers connected in parallel at each end to respective anchor plates, and guide means enable the hydraulic motor to expand and contract along a linear path longitudinally of the muscle.

6. An apparatus as defined in claim 5, wherein the hydraulic motor includes at least one anchor means which is pivotally connected to the remainder of the hydraulic motor means in order to provide more flexible movement to the muscle to which the hydraulic motor means is to be harnessed.

7. An artificial replacement muscle in combination with an implantable motive power apparatus, comprising means for harnessing the contractile force of one or more skeletal muscles while the skeletal muscles remain in their anatomic position, and means for transmitting the motive power from said means for harnessing to the artificial replacement muscle for operating the artificial muscle in a manner simulating the operation of the muscle it is replacing, wherein the means for harnessing a skeletal muscle includes a linear displacement hydraulic motor having anchor plates at each end thereof respectively adapted to be connected to the tendon material at each end of the muscle, and hydraulic fluid displacement means associated with the motor for displacing hydraulic fluid when the skeletal muscle contracts, wherein the artificial replacement muscle is a heart pump and the harness means are individually adapted to be attached to a plurality of skeletal muscles and the respective insertion tendons of said skeletal muscles are severed, and the natural motor nerves of the skeletal muscles are surgically interrupted, and the anchor plates of said harness means are adapted to be connected to each end of the respective muscle, and artificial stimulation means are provided such that the harnessed muscles will contract in sequence, wherein the anchor plates include small arrow-shaped anchor elements adapted to pierce and engage in the tendon material to which the plate is being anchored, and openings provided in a zigzag pattern along an axis at right angles to the tendon fiber alignment of the muscle, the openings being interspaced between the anchor elements and the openings being sufficient to allow suture material to be passed therethrough into the tendon material;

the subsequent biological transformation of the suture material into fibrous tissue results in binding of the anchor plate to the tendon material in such a way that the fibrous tissue is aligned between the anchor elements in general alignment normal to the tendon fiber alignment.

8. An artificial replacement muscle in combination with an implantable motive power apparatus, comprising means for harnessing the contractile force of one or more skeletal muscles while the skeletal muscles remain in their anatomic position, and means for transmitting the motive power from said means for harnessing to the artificial replacement muscle for operation the aritificial muscle in a manner simulating the operation of the muscle it is replacing, wherein the means for harnessing a skeletal muscle includes a linear displacement hydraulic motor having anchor plates at each end thereof respectively adapted to be connected to the tendon material at each end of the muscle, and hydraulic fluid displacement means associated with the motor for displacing hydraulic fluid when the skeletal muscle contracts, wherein the hydraulic pressure from the hydraulic motor effected by contraction of the harnessed muscle is connected to means for converting said pressure into electrical power.

9. An apparatus as defined in claim 8, wherein the hydraulic conduit from the hydraulic motor means to be harnessed to the muscle forms a closed circuit and a dynamo means is provided in the closed circuit whereby, as the muscle is contracted, the dynamo is forced to rotate by the hydraulic fluid pressure, thereby producing electricity.

10. An apparatus as defined in claim 9, wherein the closed circuit is unidirectional and a one-way valve prevents backflow of the hydraulic fluid, a pressure chamber is provided in the closed circuit line downstream of the dynamo, the pressure chamber including an elastic membrane adapted to be extended against a compressible fluid trapped behind the membrane thereby effecting an accumulated pressure for returning the fluid to the hydraulic motor in order to extend the muscle to its relaxed position.

11. An artificial replacement muscle in combination with an implantable motive power apparatus, comprising means for harnessing the contractile force of one or more skeletal muscles while the skeletal muscles remain in their anatomic position, and means for transmitting the motive power from said means for harnessing to the artificial replacement muscle for operating the artificial muscle in a manner simulating the operation of the muscle it is replacing, wherein the means for harnessing a skeletal muscle includes a linear displacement hydraulic motor having anchor plates at each end thereof respectively adapted to be connected to the tendon material at each end of the muscle, and hydraulic fluid displacement means associated with the motor for displacing hydraulic fluid when the skeletal muscle contracts, wherein said means for transmitting the motive power includes a conduit means for passing the hydraulic fluid and dynamo means interrupting said conduit means for converting the hydraulic pressure into electricity, and means for storing said electricity.

12. A heart replacement blood pump comprising four actively pumping chambers, two of the chambers simulating ventricles and two of the chambers simulating atria, wherein the ventricular and atrial chambers are driven reciprocally by a hydraulic motor, the four chambers being formed by the intersection of first and second partitions at right angles to each other, inlet ports are provided respectively to each of the atrial chambers and outlet ports are provided respectively to the ventricular chambers while passage means are piovided between each respective atrial chamber and ventriclular chamber, wherein the atrial chambers are actively pumping chambers as well as the ventricular chambers so as to enable venous uptake by the blood pump to occur throughout systole and into daistole but ejection of blood into the arteries occurs only during systole, wherein the hydraulic motor includes a wedge member, the apex of which is hinged to the first partition, said wedge having surfaces forming a movable wall of each of the four respective chambers such that the pendulum motion of the wedge about its hinged axis during systole will expand each atrial chamber and contract each ventricular chamber and reverse movement of the wedge during diastole will contract each atrial chamber and expand each ventricular chamber.

13. A blood pump as defined in claim 12 wherein a curved bore is provided in the housing of the blood pump with its central axis in the plane of the second partition, a curved cylinder is fixed to the wedge and adapted to slide in the curved bore, a disc concentric with the hinge axis of the wedge and in the plane of the second partition is fixed to the curved cylinder, one end of said bore being an inlet adapted to communicate with a hydraulic motive source, an expandable sealed chamber communicating with said inlet and extending within said curved bore and abutting the curved cylinder whereby, when the fluid pressure is exerted within the expandable chamber, the curved cylinder will be displaced within the bore, thereby moving the wedge fixed thereto effecting systole.

14. A blood pump as defined in claim 12, wherein the four respective chambers include two pairs of chambers, each pair having an atrial chamber and a ventricular chamber, the first pair simulating the left half of a heart and the second pair simulating the right half of a heart;

the surfaces of the wedge forming the respective movable walls of the respective chambers are in the form of independently hinged flaps on either side of the wedge, the wedge being fenestrated and having through passages communicating each side of the wedge, passage means communicating the wedge from the first pair to the second across the second partition, hydraulic fluid in the wedge spaces filling the fenestrations and passages, a predetermined amount of excess hydraulic fluid in the wedge spaces sufficient to maintain a combined wedge space volume greater than the volume of the wedges such that when conditions where the pressure of blood in the veins supplying one pair of chambers exceeds the pressure of blood in the veins supplying the other pair of chambers, the hydraulic fluid will flow from the wedge space corresponding to the one pair of chambers to the wedge space corresponding to the other pair of chambers experiencing the lower venous pressure, thereby resulting in a reduction in blood filling in the other pair of chambers experiencing the lower venous pressure and an increase in blood filling in the one pair of chambers experiencing the higher venous pressure, thus reducing the effective blood stroke volume of the other pair of chambers experiencing the lower venous pressure while the effective blood stroke volume of the one pair of chambers experiencing the higher venous pressure may be increased a corresponding amount, thereby augumenting the flow of arterial blood to the other pair of chambers which has the lower venous pressure.

15. A blood pump as defined in claim 14 wherein fluid reservoir means are provided to communicate with the wedge spaces such that fluid can be drawn into the wedge spaces between the respective flaps, the reservoir including an elastic membrane, whereby fluid will be drawn into the wedge space between the flaps against the membrane, thereby dampening the pressure exerted on the blood within the chambers of respective pairs of chambers, the degree of expansion of the wedge fluid space between the flaps between either pair of chambers being inversely proportional to respective venous pressures.