Comparison of two types of mechanical assistance in experimental heart failure.

V ARIOUS forms of mechanical assistance are now being used clinically in attempts to alleviate acute heart failure." However, the physiologic effects of each type of assisted circulation upon the various decompensation syndromes are not well known and the results of their application in human patients have not been evaluated. The multiple measurements needed and the critical condition of the patients usually preclude adequate monitoring of physiologic variables during these therapeutic procedures. The influence of mechanical assistance procedures on cardiac failure states should therefore be investigated under conditions which permit continuous observations of all important indices of cardiac function. Data reported here describe experiments in which 7 different types of cardiac failure were produced in dogs and where each type of decompensation was treated with 2 forms of mechanical assistance.