Abstract: A drive unit to control the peak pressure of air for the inflation of a left ventricular assist system is disclosed. The control of the peak pressure can address the problem of the “kick” experienced by patients when the peak inflation pressure reaches approximately 200 mm Hg. The peak pressure of the air released for the inflation cycle of the system is reduced either by the reduction of the inner diameter of the interconnect line running from the compression tank to the valve manifold or the use of a multi-valve manifold with independently controlled valves and an electronic controller to selectively open and close the valves of the manifold. Either technique, whether used alone or in combination, reduces the peak pressure of the air released for the inflation cycle to below the levels associated with the “kick,” while still meeting the operating specifications to properly inflate and deflate the system's blood pump.

Abstract: An in-series ventricular assist system for assisting the circulation of blood in a patient is disclosed. A pumping bladder is disposed in the thoractic aorta of the patient and selected physiologic events relating to each heart beat are monitored by appropriate sensors. A gas handling subsystem inflates and deflates the pumping bladder in accordance with the detected physiologic events and a predetermined set of assist system parameters. A microprocessor evaluates the effects of inflation and deflation of the pumping bladder and the corresponding assistance on the patient for each heart beat. The microprocessor is operable to alter or adjust the assist system parameters for each subsequent heart beat in accordance with the effects of assistance of the pumping bladder on the patient.