Prolonged epicardial mapping in myocardial infarction: the effects of propranolol and intra-aortic balloon pumping following coronary artery occlusion.

A methods of prolonged epicardial surface mapping of myocardial infarction by serial epicardial ECG's is described. The progression of infarction following coronary artery ligation in dogs was monitored over a 4 day period and the early and late changes in the configuration of the epicardial ECG's associated with the underlying myocardial injury were defined. The determination of the infarct size by surface mapping in vivo correlated accurately with the final infarct size determined by dehydrogenase staining in vitro. Treatment with propranolol resulted in a significant reduction in the infarct size. Treatment with intra-aortic balloon pumping did not alter the size of the myocardial infarction induced in this experimental model.