A coronary sinus system for use during cardiopulmonary bypass.

Abstract

M ANY of the initial problems associated with the use of pump-oxygenator systems have been solved, or have assumed less importance. One aspect of total body perfusion which has been given little attention is the “coronary sinus ’ ’ return system. This aspect of perfusion is frequently overlooked as a source of increased morbidity and mortality rates, regardless of the pumpoxygenator system used. The blood involved primarily represents the coronary flow returning via the coronary sinus and Thebesian vessels emptying into the right side of the heart. This return flow has been reported to be approximately 6 to 8 per cent of the total perfusion at perfusion rates of 60 to 80 ml. per kilogram of body weight per minute.4 In certain congenital and acquired cardiac lesions, this volume of blood will be considerable when the coronary flow is augmented by high bronchial artery or aortic regurgitant flow.t Some surgeons have discarded all blood aspirated from the heart during bypass. Others have utilized methods which either decrease or ablate coronary return in order to minimize the problems. These methods include cardiac arrest, intermittent occlusion, and. moderate to. profound hypothermia. It is obvious in certain situations, and particularly when patients have acquired valvular disease, that even when such adjunctive measures are employed the amount of blood returning to the heart can be considerable and it must be returned to the pump-oxygenator system whether desirable or not. The policy of discarding all such blood avoids the problems, but of necessity demands a blood reserve which, though large, may be inadequate.