Intraventricular plus intra-aortic balloon pumping during intractable cardiac arrest.

A method is presented for maintaining aortic flow by mechanical means during intractable cardiac arrest. A spherical balloon was inserted into the left ventricle while the usual intra-aortic balloon was introduced into the thoracic aorta. Ventricular fibrillation was induced by direct current. The pumps operating the two balloons were adjusted to inflate the intraventricular balloon during one third of the pumping cycle and the intra-aortic balloon during the next two thirds of the same cycle. The intraventricular balloon capacity varied from 40 to 110 ml (six dogs weighing 16-24 kg) while the intra-aortic balloon capacity was 20 ml. An optimal pumping rate of 75 beats/min maintained an aortic flow of 0.9-1.5 ml/beat/kg and a mean pressure into the brachiocephalic trunk of 110 +/- 12.5 mm Hg (mean +/- SD). These experimental data indicate that an easily applied mechanical device system (needing no extracorporeal circulation) may be used to bridge the time between intractable cardiac arrest and implantation of an artificial heart or transplantation.