Relation between the extent of the myocardial lesion and the state of the coronary bed in acute myocardial infarction

: The probability of combined lesion of both ventricles in acute myocardial infarction (AMI) is discussed. In cases of proximal stenosis or occlusion of the right coronary artery, both inferior and right-ventricular (RV) AMI may develop. ECG recordings from the V3R-V6R, V3RIII, V4RIII leads were used for the diagnosis of RV AMI. Elevated ST segment plus the formation of Q waves and a negative T wave in the recordings from these leads indicate RV AMI in the presence of inferior AMI. The extent of myocardial lesion, estimated on the basis of maximum plasma MB CPK activity, is greater in cases of inferior AMI with electrocardiographic signs of RV AMI, as compared to inferior AMI free of such signs.