Acute myocardial infarction in a patient with anomalous left coronary artery origin and primary antiphospholipid syndrome

Anomalous left main coronary artery (LMCA) originating from the right coron ary sinus and running between the aorta and pulmonary trunk is a rare conge nital condition. Although this disease is known to be associated with myoca rdial infarction and sudden death, the precise mechanism is uncertain. A 14 -year-old merle with this anomaly developed myocardial infarction during ex ercise complicated by primary antiphospholipid syndrome. He was admitted to hospital with persistent chest pain and sudden cardiac collapse that occur red while he was running. Cardiac catheterization demonstrated a narrowed s egment in the LMCA and impaired blood How, prompting a diagnosis of extensi ve anterior myocardial infarction. Emergency bypass surgery was performed u sing a single saphenous vein graft to the left anterior descending artery. Postoperative angiography showed the presence of an anomalous LMCA arising from the right sinus of Valsalva and running between the great vessels. The aortic samples were pathologically normal. He was discovered to also have primary antiphospholipid syndrome and was discharged without symptoms after warfarin therapy. Complicated primary antiphospholipid syndrome may trigge r myocardial infarction in asymptomatic patients with this type of coronary anomaly.