Cardiac Medicine Certification (CMC) Practice Exam

The finding of ST elevation in the right precordial leads V3R to V6R is highly specific for right ventricular myocardial infarction. This specificity arises because these leads directly assess the right ventricle's position and function, which is crucial in identifying right-sided infarctions. In cases where there is inferior ST elevation (typically observed in leads II, III, and aVF), one should also consider the possibility of concomitant right ventricular involvement, particularly when there is a significant occlusion in the right coronary artery. However, the clear elevation in V3R to V6R is a direct indication of right ventricular injury, making it a distinct and telling sign. The other findings such as ST depression in V1 are more indicative of general myocardial ischemia rather than a specific right ventricular event. Reciprocal changes in V1 and V3, while they can appear in various types of infarctions, do not have the same specificity for right ventricular myocardial infarction as the direct right precordial lead elevation.