HETEROGENEITY OF CORONARY BLOOD FLOW IN HUMAN CORONARY ARTERY DISEASE AND EXPERIMENTAL MYOCARDIAL INFARCTION

Although abnormalities of coronary flow are no doubt importantly related to mechanisms producing sudden death in myocardial infarction, the evaluation of coronary flow in the presence of coronary artery disease is difficult. Ideally one desires an accurate measurement of average flow and a quantitative assessment of the manner in which flow is distributed within the heart. Average coronary flow has been reported to be the same in individuals with and without coronary artery disease. Possible explanations for the lack of a discrepancy include arteriolar dilatation sufficient to maintain normal flow at rest, reductions in volume of areas of low flow and wide variations of flow within individual groups. An equally plausible alternative is that reported measurements of flow in coronary disease are incorrectly high because of limitations of conventional methods for assessing heterogeneous flow. When employing inert gas technics, methods of test gas delivery and blood gas analysis must be adequate for areas of below average flow. When appropriate methods are utilized, areas of below average flow appear to be demonstrable in human coronary artery disease and experimental myocardial infarction. The inclusion of these areas alters the calculation of average flow significantly. Areas of below average flow may be uniquely important in the clinical manifestations of coronary artery disease. © 1969.