A 60 year old woman with a large anterior wall myocardial infarction developed severe hypotension 12 hr after admission to the coronary care unit. X rays showed an enlarged cardiac shadow and echocardiography signs of pericardial effusion. Swan Ganz catheterization revealed severe venous hypertension and no suggestion of ventricular septal rupture. Emergency surgery, initiated with partial cardiopulmonary bypass, showed a 1 cm tear of the anterior wall of the left ventricle, close to the left anterior descending artery. A successful repair was obtained by suture on teflon pledgets. After a difficult postoperative course, the patient was doing well 8 months after surgery.