Importance of collateral circulation for compensating for myocardial ischemia during physical loading in ischemic heart disease patients

Exercise-induced electrocardiotopographic ST depression was analysed with reference to the presence of a collateral blood flow, angiographic assessment of the coronary bed and a history of myocardial infarction in 94 coronary patients. The presence of a collateral blood flow is shown to contribute to a more rapid elimination of post-exercise myocardial ischemia, irrespective of the number of affected coronary arteries and the history of myocardial infarction. Myocardial ischemia developing in response to exercise is particularly extensive in case of multiple coronary arterial lesions and the presence of a collateral blood flow.