The effects of isoprenaline on epicardial ST-segment elevation, lactate production, and myocardial blood flow following coronary artery ligation

Abstract

Isoprenaline was infused at low and high rates into anaesthetized dogs after ligation of the left anterior descending coronary artery, the resultant changes in epicardial ST-segment elevation being compared with lactate production and myocardial blood flow in the infarcting myocardium. Although ST elevation was increased at both infusion rates, there was no change in the arterial-local coronary venous difference of lactate concentration nor in myocardial blood flow at the centre of the infarct. The results suggest that the relationship between epicardial ST-segment elevation and other indices of ischaemic myocardial injury is complex and requires further evaluation.