False coronary lumen originating from left main coronary artery dissection causing acute myocardial infarction--a case report.

Spontaneous coronary artery dissection is a rare cause of acute myocardial infarction, which is infrequently diagnosed antemortem. The majority of the previously reported cases were found in women of whom a significant proportion presented during pregnancy or the postpartum period. A case is presented of an acute myocardial infarction in a 37-year-old woman, unrelated to pregnancy or the postpartum state, with an unusual spontaneous coronary dissection that was angiographically documented 6 days after thrombolytic therapy. Originating in a small dissection in the left main coronary artery, a false lumen parallel to the left anterior descending coronary artery (LAD) with a separation of the lumina of up to 1 mm was found with a reentry of the false lumen into the LAD in its mid portion. Both lumina were perfused and the true lumen of the LAD showed a 50% to 60% diameter stenosis. Because no signs of ongoing ischemia could be detected at rest or during exercise, the patient was treated medically. Two months later, repeat coronary angiography documented a complete obliteration of the false lumen with moderate stenosis of the proximal LAD. Pathophysiologic aspects and treatment options of spontaneous coronary artery dissections are discussed.