ABSTRACT
Common complications of acute dissecting aortic aneurysm include external rupture with fatal hemorrhage, dissection and occlusion of major branches of the aorta, and aortic regurgitation. Although lesions of the pulmonary vessels may complicate nondissecting thoracic aneurysms, pulmonary vascular lesions caused by acute dissecting aortic aneurysm have not been described. Extravasated blood also was present in the adventitia of the ascending and transverse portions of the aorta, pulmonary trunk, right and left main pulmonary arteries, and left atrium. Extravasated blood also surrounded the proximal right and left coronary arteries, and the lumen of the right coronary artery was slightly compressed by the adventitial blood. The aortic aneurysm, which originally had dissected through only a part of the media, ruptured through the entire aortic media at a site just above the aortic valve. Only the right pulmonary artery was compressed since it was located between the left atrium and aorta.
