A simple heparinless venoarterial bypass (HL-VAB) system without oxygenation has been developed for the support of the failing heart. Experiments in animals with cardiogenic shock showed that the aortic root pressure (coronary flow) was elevated immediately by HL-VAB. Within 90 minutes of HL-VAB, left ventricular dyskinesia disappeared and the bypass was successfully removed from all animals. Normal blood levels could easily be maintained by ventilatory support with 40% oxygen, if the bypass flow was not more than one third of the cardiac output. This technique was employed to mechanically support the circulation before and after surgery in five critically ill patients who underwent open-heart surgery. Four of the five patients survived. This technique of mechanical circulatory assistance appears to be simpler and more effective than other techniques employed clinically.
Wakabayashi A, Nakamura Y, Murphy KJ, Stemmer EA, Connolly JE. Heparinless Venoarterial BypassIts Application in the Treatment of Experimental Cardiogenic Shock. Arch Surg. 1974;108(4):497–501. doi:10.1001/archsurg.1974.01350280101016