Left main coronary artery compression during primary pulmonary hypertension.

Primary pulmonary hypertension (PPH) is often associated with angina-like chest pain, the mechanism of which is controversial. A 37-year-old woman with severe PPH and angina had transient ischemic ECG changes and reversible anterior perfusion defect on 201thallium scintigraphy. Coronary angiography revealed severe stenosis of the left main coronary artery (LMCA) and otherwise normal vessels. After heart-lung transplantation, examination of the explanted heart showed normal coronary arteries. Compression of the LMCA by the dilated pulmonary artery trunk was responsible for myocardial ischemia. This mechanism should be considered in patients with PPH and angina and might contribute to the high sudden death rate.