Myocardial infarction and left ventricular free wall rupture in a patient with a prior pericardiectomy

Abstract

L eft ventricular free wall rupture (LVFWR) is a rare complication of acute myocardial infarction (AMI), occurring in approximately 2% of cases (1), and is often fatal because of the development of hemopericardium and tamponade. We describe a patient in whom free wall rupture occurred in the setting of previous pericardiectomy. Despite ongoing mediastinal hemorrhage, the diagnosis was established at cardiac catheterization and by computed tomographic scanning of the thorax, and surgical repair was performed. CASE PRESENTATIONA previously well 59-year-old man suddenly developed left shoulder pain, followed by intense central chest pain with bilateral arm radiation and diaphoresis while picking up garbage. When seen at a local nursing station, his heart rate was 140 beats/min and his blood pressure was 80/50 mmHg. An electrocardiogram showed sinus rhythm with complete right bundle branch block. There was ST segment elevation in the inferolateral leads and ST segment depression in leads V1 through V4.His cardiac risk factors included cigarette smoking, borderline hypertension and diet-controlled diabetes. He had undergone pericardiectomy for tuberculous pericarditis in 1970. He had been taking no medications.He was treated with acetylsalicylic acid. Thrombolytic therapy was not administered because of a concern about the possibility of aortic dissection. On arrival to the emergency department at the St Boniface General Hospital (Winnipeg, Manitoba), his chest discomfort persisted. His heart rate was 146 beats/min and his blood pressure was 86/54 mmHg. There were no signs of congestive heart failure and no heart murmurs. The arterial pulses were intact.The peak creatine phosphokinase and troponin T levels were 1202 U/L and 5.97 μg/L, respectively. A chest x-ray revealed right pleural effusion with an unusual dense area in the region of the right hilum.A contrast left ventriculogram revealed extravasation of contrast through the posterolateral wall of the left ventricle. Coronary angiography revealed 70% to 75% occlusion of the mid-distal circumflex artery. The mid-distal right coronary artery and the left anterior descending artery had insignificant stenosis of 40% to 50%.A transient episode of cardiac arrest with pulseless electrical activity required endotracheal intubation, inotropic support and insertion of an intra-aortic balloon pump. His hemoglobin level fell from 112 g/L to 67 g/L, and an urgent blood transfusion was initiated.Emergency transthoracic and transesophageal echocardiography were performed. The acoustic window was limited. An echo-free space with several immobile septi was identified anterior to the right ventricle. Cardiac rupture was suspected. A computed tomographic scan of the thorax confirmed extensive mediastinal hematoma in communication with the left ventricle.The cardiac surgery department was consulted and the patient was taken directly to the operating room. A defect of approximately 1 cm 2 in the posterobasal wall of the left ventricle was repaired. Coronary bypass grafting was not at...