Implantable counterpulsation cardiac assist device

摘要

A hollow tubular element is inserted in the descending aorta. The caudad end contains a pressure sensitive passive or preferably, hydraulically or electrically activated, unidirectional valve. A flexible diaphragm situated in a rigid shell affixed over an opening in the element wall divides the shell interior into first and second variable volume chambers. The first chamber opens to the artery. A continuously operating electrical pump is connected to the second chamber through a closed hydraulic system including a multi-valve chamber. The valves regulate fluid flow to the second chamber in accordance with electrical signals from the heart. Fluid flow is directed to the second chamber during cardiac diastole and away from the second chamber during cardiac systole, causing the device to function in a counterpulsation mode. The work of the heart is decreased and coronary blood flow is increased to promote the formation of new coronary collateral channels and the perfusion of the heart itself. In the event of mechanical failure, pre-implantation heart function is not impeded.