6 months follow-up after mitral transcatheter edge-to-edge repair: clinical and procedural determinates that may affect residual mitral regurgitation

Background Mitral transcatheter edge-to-edge repair (M-TEER) has emerged as a standard procedure for treatment of severe mitral regurgitation (MR). Procedural success is often defined by residual MR. However, predictors that affect course of residual MR after M-TEER remain poorly understood. Purpose To assess course of residual MR after M-TEER and to identify clinical and procedural determinates that may affect residual MR after 6 months of follow-up (FU). Methods We retrospectively analysed 386 patients undergoing M-TEER at a tertiary heart centre. MR severity was assessed immediately after the procedure and after a median of 6 months of FU. Deterioration of MR was defined as an increase in MR grade ≥ 0.5. Univariable and multivariable logistic regression models were used to identify predictors of MR deterioration. Results Within 6 months after M-TEER, MR deterioration occurred in 233 patients (60.4%). Residual MR remained unchanged in 33.2% and improved in 6.5%. Transition patterns differed significantly across all post-procedural MR groups (x2= 104.5, p<0.001). Patients with residual MR < I showed the highest rate (93.2%) of MR deterioration at FU. In multivariable analysis, residual MR was the strongest independent predictor of early deterioration (OR 0.17, 95% CI 0.09-0.33; p<0.001). Independent associations were also observed for higher EuroScore II (OR 1.07 per point, 95% CI 1.01-1.12; p=0.011), secondary vs primary MR (OR 0.51, 95% CI 0.28-0.96; p=0.036), smoking status (OR 0.38, 95% CI 0.19-0.78; p=0.008), coronary artery disease (OR 0.50, 95% CI 0.26-0.95; p=0.034) and arterial hypertension (OR 2.40, 95% CI 1.01-5.69; p=0.048). Conclusion Early deterioration of residual MR after M-TEER is frequent. Residual MR represents the dominant determinate of early MR worsening, while baseline risk profile and MR aetiology further modulate risk. These findings underscore that residual MR on its own does not fully capture procedural success and highlight the need for early FU strategies.