The impact of recurrent mitral regurgitation after surgical or transcatheter mitral valve repair: a comprehensive review and a meta-analysis

Abstract OBJECTIVES Recurrent mitral regurgitation (MR) is typically defined as mitral regurgitation that is moderate or severe on follow-up echocardiography after the intervention. This meta-analysis summarizes the results of all available studies on the impact of recurrent mitral regurgitation on clinical outcomes after intervention. METHODS Medline, EMBASE, PubMed, and Web of Science were searched from January 2000 to August 2024 for original studies reporting outcomes about the clinical impact of recurrent mitral regurgitation. Five clinical outcomes were analyzed: reoperation, cardiovascular mortality, readmission, heart failure, and NYHA functional classification. The summary Odds Ratio (OR) with 95% confidence interval (CI) was used to assess the risk of clinical outcomes. RESULTS A total of 22 studies were included in the final analysis, involving 5,804 patients, of which 960 had recurrent MR. The overall pooled incidence of recurrent MR is 16.54%. Secondary or primary MR patients with recurrent MR after intervention had higher rates of reoperation (OR = 6.25, 95% CI, 2.95–14.41; P ＜0.001) or (OR = 22.54, 95% CI, 14.96–33.98; P ＜0.001), cardiovascular mortality(OR = 5.26, 95% CI, 2.35–11.77; P＜0.001) or (OR = 1.68, 95% CI, 1.32–2.14; P＜0.001). The rates were also high in readmission(OR = 3.95, 95% CI, 2.56–6.10; P < 0.001), heart failure incidence(OR = 2.87, 95% CI, 1.75–5.11; P < 0.001), and the number of NYHA class III/IV (OR = 5.40, 95% CI, 3.01–9.70; P＜0.001) for recurrent MR of secondary MR. However, no significant association was found between recurrent MR of primary MR and the incidence of NYHA class III/IV. (OR = 1.02, 95% CI, 0.47–2.22; P = 0.96). CONCLUSIONS Recurrent MR is associated with a higher rate of reoperation, readmission, cardiovascular mortality, incidence of heart failure, and NYHA class III/IV number. However, recurrent MR of primary MR is not correlated with the NYHA class III/IV.