[Myocardial bridging as a cause of coronary insufficiency].

The authors studied the clinical and angiographic findings in two patients who had a myocardial bridge (MB) in the right anterior descending coronary artery and did not have any arteriosclerotic lesions in the coronary arteries. The two patients were men, 57 and 58 years old. Both had a history of arterial hypertension (for 19 years and 6 months, respectively) and angina pectoris (for 7 years and 6 months, respectively). The resting EKG showed subepicardial ischemia in one and was normal in the other. The stress test was positive in both. Coronary artery angiography showed an MB in the right anterior descending coronary artery which caused a systolic constriction of 90% and 80%, 3 and 2 cm. long. Both patients had left ventricular hypertrophy. The authors conclude that MB is a frequent cause of coronary insufficiency and that the appearance of symptoms and their severity depends on the degree of systolic constriction, greater than 75%, and on the presence of left ventricular hypertrophy. The majority of patients are controlled with medical treatment and only a small number require surgical therapy.