Natural history of mild aortic valve disease untreated at the time of rheumatic mitral valve replacement

Abstract

OBJECTIVES: The aim of this study was to examine long-term clinical outcomes and to assess the eventual need for aortic valve replacement (AVR) in patients with mild aortic valve disease (AVD) at the time of mitral valve replacement.

METHODS: Between 1990 and 2015, 1231 patients undergoing mitral valve replacement were reviewed, stratifying subjects as those with AVD (n = 363) or without AVD (NA; n = 868). Primary end points were progressive AVD (grade ≥ II) and subsequent AVR. Overall mortality and valve-related complications served as secondary end points. Propensity score matching was used for risk adjustment (n = 320 in each group).

RESULTS: No differences in postoperative complications or clinical outcomes were observed between groups. The 20-year overall survival was similar (before matching: NA 86.1% vs AVD 80.8%, P = 0.128; after matching: 83.5% vs 81.1%, P = 0.425). Of the entire cohort, progressive AVD was observed in 162 patients, and significant AVD (grade ≥ III) was observed in only 60 patients. Subsequent AVR was required in 37 patients due to mitral valve (MV) dysfunction or severe aortic stenosis. The 20-year freedom from significant AVD and subsequent AVR was significantly higher in the NA group than in the AVD group before and after matching (before: NA, 96.5% vs 73.7%, P < 0.001; AVD, 98.5% vs 82.3%, P < 0.001; after: 98.1% vs 73.3%, P < 0.001; 99.3% vs 82.5%, P < 0.001, respectively).

CONCLUSIONS: Although progressive AVD did not significantly impact long-term survival during the follow-up period, those patients qualifying initially as mild AVD may eventually progress to significant AVD after the first 5 postoperative years. Therefore, aggressive echocardiography should be performed at 5-year lapse after mitral valve replacement to determine the appropriate timing of AVR.