The natural history of aortic valve disease after mitral valve surgery

OBJECTIVES The present study evaluates the long-term course of aortic valve disease and the need for aortic valve surgery in patients with rheumatic m itral valve disease who underwent mitral valve surgery. BACKGROUND Little is known about the natural history of aortic valve diseas e in patients undergoing mitral valve surgery for rheumatic mitral valve di sease. In addition:here is no firm policy regarding the appropriate treatme nt of mild aortic valve disease while replacing the mitral valve. MEHTODS One-hundred thirty-one patients (44 male, 87 female; mean age 61 +/ - 13 yr, range 35 to 89) were followed after mitral valve surgery for a mea n period of 13 +/- 7 years, Al patients had rheumatic heart disease. Aortic valve function was assessed preoperatively by cardiac catheterization and during follow-up by transthoracic echocardiography. RESULTS At the time of mitral valve surgery, 59 patients (45%) had mild aor tic valve disease: 7 (5%) aortic stenosis (AS), 58 (44%) aortic regurgitati on (AR). At the end of follow-up, 96 patients (73%) had aortic valve diseas e: 33 AS (mild or moderate except in two cases) and 90 AR (mild or moderate except in one case). Among patients without aortic valve disease at the ti me of the mitral valve surgery, only three patients developed significant a ortic valve disease after 25 years of follow-up procedures. Disease progres sion was noted in three of the seven patients with AS (2 to severe) and in six of the fifty eight with AR (1 to severe). Fifty two (90%) with mild AR remained stable after a mean follow-up period of 16 years. In only three pa tients (2%) the aortic valve disease progressed significantly after 9, 17 a nd 22 years. In only six patients of the entire cohort (5%), aortic valve r eplacement was needed after a mean period of 21 years (range 15 to 33). In four of them the primary indication for the second surgery was dysfunction of the prosthetic mitral valve. CONCLUSIONS Our findings indicate that, among patients with rheumatic heart disease, a considerable number of patients have mild aortic valve disease at the time of mitral valve surgery. Yet most do not progress to severe dis ease, and aortic valve replacement is rarely needed after a long follow-up period. Thus, prophylactic valve replacement is not indicated in these case s. (C) 1999 by the American College of Cardiology.