Progressive thoracic aortic dilatation after aortic valve replacement.

Aneurysms of the ascending aorta developed after aortic valve replacement for chronic aortic insufficiency in four cases. Two of the aneurysms were complicated by dissection; one patient died. Rheumatic disease has become a less common cause of pure aortic regurgitation, and a number of etiologies primarily involving the wall of the aorta are now recognized. Although appropriately timed aortic valve replacement can prevent the irreversible left ventricular depression associated with chronic aortic insufficiency, careful evaluation of the thoracic aorta on serial postoperative chest radiographs is warranted, because the underlying pathologic process may proceed in the aortic wall with eventual aneurysm formation.