To determine the natural history of patients with a total occlusion of a single coronary artery, we searched the Duke Databank for Cardiovascular Disease to find all patients who underwent a first coronary angiogram >2 days after a symptomatic myocardial infarction between 1969 and 1994. Patients who underwent angiography >30 days after the acute event had a low risk of death in the first year (3%), and a proximal left anterior descending coronary occlusion did not confer substantially higher risk of death (4%). Patients undergoing angiography <30 days after the acute event had a higher mortality (5%), especially those with proximal left anterior descending occlusion (10%). The time from the acute event to angiography was a predictor of death ( p = 0.04). Despite low 1-year mortality rates, patients with total occlusion of an isolated coronary vessel treated medically had substantial mortality, myocardial infarction, and revascularization rates over a long-term follow-up period. (Am Heart J 1997;133:393-9.)