Comparison of Valve Structure, Valve Weight, and Severity of the Valve Obstruction in 1849 Patients Having Isolated Aortic Valve Replacement for Aortic Valve Stenosis (With or Without Associated Aortic Regurgitation) Studied at 3 Different Medical Centers in 2 Different Time Periods

Abstract

Background— Aortic valve replacement (AVR) for patients with aortic stenosis (AS) has now been available for 45 years. During this period, indications for the procedure have changed. Methods and Results— Operatively excised stenotic aortic valves (with or without associated aortic regurgitation and without associated mitral valve disease) from 3 different medical centers (National Institutes of Health, Georgetown University Medical Center, and Baylor University Medical Center) were examined during 2 different time periods by the same physician to compare aortic valve structure, valve weight, age at operation, preoperative transvalvular peak pressure gradient, calculated aortic valve area, and whether simultaneous coronary artery bypass grafting (CABG) was performed. Compared with the first 3 decades (1961–1990) of AVR, patients having this operation during the fourth and fifth decades (1991–2004) had a lower frequency of congenitally malformed aortic valves, a higher frequency of tricuspid aortic valves, an older age, valves of lighter weight and lower transvalvular peak pressure gradients, and more often simultaneous CABG. Conclusions— Although patients having isolated AVR for AS in the present and last decade were older than in the first 3 decades of valve replacement surgery, congenitally malformed aortic valves continue to be more common than tricuspid aortic valves, but the degree of AS and therefore, valve weight was significantly lower than in the earlier decades.