Coronary Blood Flow and Myocardial Oxidative Metabolism at Rest and during Exercise in Subjects with Severe Aortic Valve Disease

AVAILABLE data concerning coronary flow in intact human subjects have in- dicated that there is a strong tendency for the blood flow per unit weight of myocardium to fall in the usual range under a wide variety of circumstances and for the coronary vessels to be capable of adapting themselves to most situations sufficiently well to maintain usual coronary flow as long as myocardial metabolism is not deranged.' When myocardial meta- bolism is deranged, the coronary circulation adapts to these derangements as, for example, in thyrotoxicosis2 and thiamine deficiency.3 The question of adaptation of human coro- nary flow to mechanical interference prompt- ed the present study of coronary blood flow in subjects with aortic valve disease because of the following considerations.