Acute type-B aortic dissection in association with isthmic coarctation

In November 1998, a 29-year-old man was admitted to another hospital with s udden onset of epigastric pain that suggested an acute abdominal problem. B ecause an echocardiogram raised the suspicion of acute dissection of the ab dominal aorta, the patient was referred to our unit for further evaluation. On admission, he denied any history of heart disease, reporting only a rece nt diagnosis of hypertension. His blood pressure was 150/80 mmHg and his pu lse rate was 65 beats/min; radial pulses were present and symmetrical, whil e femoral pulses were reduced. Chest radiography showed a widened superior mediasrinum, and electrocardiography showed sinus bradycardia with left ven tricular hypertrophy. A transthoracic 2-dimensional echocardiogram revealed a flap in the descending thoracic aorta. Both computed tomographic (CT) sc anning (Fig. 1) and nuclear magnetic resonance imaging (MRI) confirmed the presence of a type-B dissection starting just below the origin of the left subclavian artery; the MRI also suggested the presence of an isthmic coarct ation (Fig. 2). At first, the patient was treated medically Despite control of his hyperten sion, the persistence of interscapular pain was considered an indication fu r surgical repair. Through a posterolateral thoracotomy, we observed marked dilatation of the descending aorta, with evidence of a subadvenritial hematoma that involved the distal aortic arch and extended below the diaphragm. Adequate control o f the aortic arch appeared impossible through this approach, for the lesion appeared to require correction under deep hypothermic circulatory arrest. Moreover, perfusion through the femoral vessels appeared to be hazardous, s o we performed a median sternotomy with cannulation of the ascending aorta and both venae cavae.