Causes of pure aortic regurgitation in patients having isolated aortic valve replacement at a single US tertiary hospital (1993 to 2005).

BACKGROUND The causes of aortic regurgitation (AR) severe enough to warrant aortic valve replacement (AVR) have received little attention in the last 20 years. METHODS AND RESULTS We analyzed the causes of pure AR in 268 patients > 20 years of age having isolated AVR at Baylor University Medical Center from 1993 to 2005 that was unassociated with mitral stenosis, mitral valve replacement, or a previous operation involving a cardiac valve or ascending aorta. In 122 patients (46%), the AR resulted from a problem with the aortic valve: congenital malformation unassociated with infective endocarditis, 66 patients (54%); infective endocarditis, 46 patients (38%; 15 with bicuspid valves); probable rheumatic heart disease, 8 patients (6%); and miscellaneous, 2 patients (2%). In the other 146 patients (54%), the AR was the consequence of a condition affecting the ascending aorta: dissection, 28 patients (19%); the Marfan syndrome or its forme fruste variety, 15 patients (10%); aortitis, 12 patients (8%), and in the remaining 91 patients (62%), the cause of the AR was not determined. This latter group was the oldest (mean age 66 years), 83 (91%) had hypertension, 26 (29%) had small calcific deposits in the valve cusps, and 46 (51%) had simultaneous coronary artery bypass grafting. CONCLUSIONS The causes of pure AR severe enough to warrant isolated AVR are diverse. The most common category in this study was "cause unclear."