An autopsy case of a ruptured pseudoaneurysm of the ascending aorta complicated by previous cardiac surgery for ventricular septal defect

• A case report; man died from the rupture of the aneurysm of the ascending aorta.
• Histological examination revealed tissue defects by the suture and disrupted media.
• Aortic cannulation was presumed to be the cause of pseudoaneurysm.

A man in his thirties was found dead in bed. He had undergone repair of a ventricular septal defect in his infancy and had a 2-month history of antemortem chest pain. On autopsy, a ruptured saccular aneurysm of the ascending aorta was identified, and the right thoracic cavity was found to contain coagulated blood. The oval ostium of the aneurysm was smoothly endothelialized and a black suture was found near its edge. Histological analysis revealed a defect of the intimal and medial layers in the wall of the aneurysm and hypertensive changes in several organs. The cause of death was presumed to be the rupture of a pseudoaneurysm at the aortic cannulation site after a long postoperative period. In the present case, preexisting hypertension was suspected as the cause of the formation and rupture of the pseudoaneurysm. In case of unexpected death, it is important to examine the past medical history even after a long postoperative period.