Normal single coronary artery and myocardial infarction.

A single left coronary artery was found in an asymptomatic 21-year-old man who initially had electrocardiographic and vectorcardiographic evidence of anterolateral myocardial infarction. The single left coronary artery, which supplied the distribution of both the left and right coronary arteries, was free of disease at catheterization. There has been no previous association of a normal single left coronary artery and anterior myocardial infarction. Patients with the finding of a single coronary artery should be watched closely, as this may represent a potentially fatal condition.