[Spontaneous Rupture of Ascending Aorta:Report of Two Cases].

Spontaneous rupture of the aorta is a rare, lethal condition that is hard to diagnose preoperatively. We report two cases of patients who presented with sudden-onset chest or pharyngeal pain. Contrast-enhanced computed tomography (CT) showed an ulcer-like projection, mediastinal hematoma, and pericardial effusion, but no definitive intimal flap. Emergency surgery was performed with a tentative diagnosis of thrombosed-type aortic dissection. In both cases, there was a localized aortic transmural laceration with a thrombus near the sino-tubular junction on the pulmonary artery side. Based on a focal intimal defect with no or minimal dissection in adjacent area, the diagnosis of spontaneous rupture of the aorta was made. Both patients were successfully treated with replacement of the ascending aorta and had favorable outcomes. When hemopericardium or mediastinal hematoma is present without clear evidence of aortic aneurysm or dissection, spontaneous rupture of the aorta must be considered, as prompt surgical intervention is crucial for survival.