Cardiac assist apparatus

Claim 1

In a cardiac assist system including: first fluid pressure responsive means, herein termed a peri-cardiac assist means, for compressing a portion of a heart during systole and decompressing it during diastole; second fluid pressure responsive means, herein termed a peri-aortic jacket means, for moving blood volume in the aorta of the heart during diastole and suddenly increasing vascular space during systole to "unload" the heart; first and second fluid pressure supply means coupled respectively to the first and second fluid pressure responsive means for alternatively supplying fluid pressure thereto, each of the fluid pressure supply means being adapted for fluid pressure communication with different selected body muscle, respectively; pressure regulator means for generating positive and negative pressures operatively interconnected with the fluid pressure supply means and the fluid pressure responsive means; sensor means adapted for sensing the heart and for generating sensing signals; and means responsive to the sensing signals for generating stimulation pulses to the selected muscles, the improvement comprising said pressure regulator means coupled between said first fluid pressure supply means and said first fluid pressure responsive means, and coupled between said second fluid pressure supply means and said second fluid pressure responsive means, said pressure regulator means comprising a multi-chamber assembly including: a first closed fluid pressure chamber of toroidal configuration having an open center; a second closed fluid pressure chamber positioned within the open center thereof and encircled by the first chamber; a rigid plate receiving said first and second chambers on a surface thereof; third and fourth closed fluid pressure chambers, the third being positioned within the open center of and encircled by the fourth which is of toroidal configuration, the third and fourth chambers being received on a surface of the rigid plate opposite to the surface receiving the first and second chambers; all four fluid pressure chambers are formed of a flexible elastic material adapted for interacting with the fluid supplied by the first and second fluid pressure supply means, and means operatively supporting the multi-chamber assembly for expansion and contraction; individual ports opening into each of the four fluid pressure chambers, and fluid pressure conduit means connecting the first chamber by means of its port to the first fluid pressure supply means, fluid pressure conduit means connecting the second chamber by means of its port to the peri-cardiac assist means; fluid pressure conduit means connecting the third chamber by means of its port to the peri-aortic jacket means and fluid pressure conduit means connecting the fourth chamber by means of its port to the second fluid pressure supply means whereby: the application of fluid pressure to the first chamber at diastole causes expansion of both the first chamber and second chamber, movement of the plate against the third and fourth chambers and contraction thereof, resulting in the compression of the third and fourth chambers and a negative suction pressure in the second chamber and consequently in the peri-cardiac assist means; at the same time the peri-aortic jacket means is inflated; and the alternate application of fluid pressure to the fourth chamber at systole causes expansion of the fourth chamber and the third chamber, movement of the plate against the first and second chambers and contraction thereof, resulting in compression of the first and second chambers and a negative suction pressure in the third chamber and consequently in the peri-aortic jacket means and at the same time the peri-cardiac assist means is inflated.