Injury to ascending aorta by partial-occlusion clamp during aorta-coronary bypass.

Disease of the proximal ascending aortic wall from prolonged, poorly controlled hypertension predisposed to intimal injury after clamp compression. This creates a spectrum of problems: (1) intimal tear with late formation of a localized aneurysm, (2) delayed acute dissecting aneurysm, and (3) intraoperative acute dissecting aneurysm. Principles of management are discussed.