counterpulsation /-pulsā″shən/ [L, contra + pulsare, to beat] , 1. the action of a circulatory-assist pumping device that is synchronized with cardiac systole and diastole to decrease the work of the heart. 2. the process of increasing the intraaortic pressure in diastole by inflation of an intraaortic balloon and deflation of the balloon immediately before the next systole.
