Reduction of the oxygen utilization of the heart by left heart bypass.

• Keports of support of the heart in acute failure both in man and in experimental animals" have been published. The means investigated include: (1) heart-lung bypass, from the cava through an oxygenator and pump to the aorta;'" (2) veno-arterial pumping without oxygenator ; ' ' ' 3 ' 4 > (3) aortic synchronized counter pulsation to lower the pressure during left ventricular ejection and to raise it when the valves are closed; and (4) left heart bypass, from left atrium to aorta.