Collateral Flow in the Heart at Different Aortic Perfusion Pressures Using Left Heart Bypass

Abstract
Intercoronary arterial flow increased as aortic pressure rose. With the normally beating heart, left heart bypass augmented intercoronary flow by 25%. With the fibrillating heart, intercoronary flow was negligible with hand pumping alone but was raised to almost normal levels with left heart bypass. The significance of these observations is discussed.