Circulatory assist devices are needed for immediate temporary treatment of acute myocardial infarction, and for postcardiotomy patients. They also are being developed for longer term help to ambulatory patients with chronic heart failure. Extracorporeal blood pumps are also used during cardiac surgery. Pneumatic and electromagnetically actuated pulsatile assist devices have been investigated, and in recent years there has been development of continuous flow rotary blood pumps, which do not require valves, but do need sliding bearings and seals, which limit their usefulness. There is still a controversy, also, concerning the adequacy of continuous flow assistance, and a biological need for pulsatile blood flow.
The aim of the Phase I effort was to determine the feasibility of a vibratory orbiting blood pump (VOBP) in which the orbiting circulator is spring mounted and actuated by an external magnetic drive, eliminating any bearings or seals in the blood path. An experimental pump has been built which provides outputs in the same range as existing nutating blood pumps. A preliminary design of a practical VOBP has been generated, a major feature of which is the inclusion of a bearingless, sealless, low cost, disposable pumping element. A Phase II program for the development of tested prototypes is presented.
