Evolution of tricuspid regurgitation after transcatheter edge-to-edge mitral valve repair for secondary mitral regurgitation and its impact on mortality

Aim: To evaluate short-term changes in tricuspid regurgitation (TR) after transcatheter edge-to-edge mitral valve repair (M-TEER) in secondary mitral regurgitation (SMR), their predictors and impact on mortality. Methods and results: This is a retrospective analysis of SMR patients undergoing successful M-TEER (post-procedural mitral regurgitation ≤2+) at 13 European centres. Among 503 patients evaluated 79 (interquartile range [IQR] 40-152) days after M-TEER, 173 (35%) showed ≥1 degree of TR improvement, 97 (19%) had worsening of TR, and 233 (46%) remained unchanged. Smaller baseline left atrial diameter and residual mitral regurgitation 0/1+ were independent predictors of TR ≤2+ after M-TEER. There was a significant association between TR changes and New York Heart Association class and pulmonary artery systolic pressure decrease at echocardiographic re-assessment. At a median follow-up of 590 (IQR 209-1103) days from short-term echocardiographic re-assessment, all-cause mortality was lower in patients with improved compared to those with unchanged/worsened TR (29.6% vs. 42.3% at 3 years; log-rank p = 0.034). Baseline TR severity was not associated with mortality, whereas TR 0/1+ and 2+ at short-term follow-up was associated with lower all-cause mortality compared to TR 3/4+ (30.6% and 35.6% vs. 55.6% at 3 years; p < 0.001). A TR ≤2+ after M-TEER was independently associated with a 42% decreased risk of mortality (p = 0.011). Conclusion: More than one third of patients with SMR undergoing successful M-TEER experienced an improvement in TR. Pre-procedural TR was not associated with outcome, but a TR ≤2+ at short-term follow-up was independently associated with long-term mortality. Optimal M-TEER result and a small left atrium were associated with a higher likelihood of TR ≤2+ after M-TEER.