Purpose of Review: To provide a detailed overview of complications associated with MitraClip therapy and its development over time with the aim to alert physicians for early recognition of complications and to offer treatment strategies for each complication, if possible. Recent Findings: The MitraClip system (MC) is the leading transcatheter technique to treat mitral regurgitation (MR) and has been established as a safe procedure with very low adverse event rates compared to mitral surgery at intermediate to high risk or in secondary MR. Lately, the fourth MC generation has been launched with novel technical features to facilitate device handling, decrease complication rates, and allow the treatment of even complex lesions. Summary: Although the complication rate is low, adverse events are associated with increased morbidity and mortality. The most common complications are bleeding, acute kidney failure, procedure-induced mitral stenosis, and an iatrogenic atrial septal defect with unknown clinical impact.

For patients with functional mitral regurgitation (FMR) and symptomatic heart failure (HF), randomized trials of mitral transcatheter edge-to-edge repair (M-TEER) have produced conflicting results. This study sought to assess the impact of M-TEER on hospitalization rates, and explore the effects of M-TEER on patients who did or did not have a history of recent HF hospitalizations before undergoing M-TEER. RESHAPE-HF2 (Randomized Investigation of the MitraClip Device in Heart Failure: 2nd Trial in Patients with Clinically Significant Functional Mitral Regurgitation) included patients with symptomatic HF and moderate to severe FMR (mean effective regurgitant orifice area 0.25 cm²; 14% >0.40 cm², 23% <0.20 cm²) and showed that M-TEER reduced recurrent HF hospitalizations with and without the addition of cardiovascular (CV) death and improved quality of life. We now report the results of prespecified analyses on hospitalization rates and for the subgroup of patients (n = 333) with a HF hospitalization in the 12 months before randomization. At 24 months, the time to first event of CV death or HF hospitalization (HR: 0.65; 95% CI: 0.49-0.85; P = 0.002), the rate of recurrent CV hospitalizations (rate ratio [RR]: 0.75; 95% CI: 0.57-0.99; P = 0.046), the composite rate of recurrent CV hospitalizations and all-cause mortality (RR: 0.74; 95% CI: 0.57-0.95; P = 0.017), and of recurrent CV death and CV hospitalizations (RR: 0.76; 95% CI: 0.58-0.99; P = 0.040), were all lower in the M-TEER group. The RR of recurrent hospitalizations for any cause was 0.82 (95% CI: 0.63-1.07; P = 0.15) for patients in the M-TEER group vs control group patients. Patients randomized to M-TEER lost fewer days due to death or HF hospitalization (13.9% [95% CI: 13.0%-14.8%] vs 17.4% [95% CI: 16.4%-18.4%] of follow-up time; P < 0.0001, and 1,067 vs 1,776 total days lost; P < 0.0001). Patients randomized to M-TEER also had better NYHA functional class at 30 days and at 6, 12, and 24 months of follow-up (P < 0.0001). A history of HF hospitalizations before randomization was associated with worse outcomes and greater benefit with M-TEER on the rate of the composite of recurrent HF hospitalizations and CV death (P_interaction = 0.03) and of recurrent HF hospitalizations within 24 months (P_interaction = 0.06). These results indicate that a broader application of M-TEER in addition to optimal guideline-directed medical therapy should be considered among patients with symptomatic HF and moderate to severe FMR, particularly in those with a history of a recent hospitalization for HF.

Background: Concomitant tricuspid regurgitation (TR) is a common finding in mitral regurgitation (MR). Transcatheter repair (TMVR) is a favorable treatment option in patients at elevated surgical risk. To date, evidence on long-term prognosis and the prognostic impact of TR after TMVR is limited. Methods: Long-term survival data of patients undergoing isolated edge-to-edge repair from June 2010 to March 2018 (combinations with other forms of TMVR or tricuspid valve therapy excluded) were analyzed in a retrospective monocentric study. TR severity was categorized and the impact of TR on survival was analysed. Results: Overall, 606 patients [46.5% female, 56.4% functional MR (FMR)] were enrolled in this study. TR at baseline was categorized severe/medium/mild/no or trace in 23.2/34.3/36.3/6.3% of the cases. At 30-day follow-up, improvement of at least one TR-grade was documented in 34.9%. Severe TR at baseline was identified as predictor of 1-year survival [65.2% vs. 77.0%, p = 0.030; HR for death 1.68 (95% CI 1.12–2.54), p = 0.013] and in FMR-patients also regarding long-term prognosis [adjusted HR for long-term mortality 1.57 (95% CI 1.00–2.45), p = 0.049]. Missing post-interventional reduction of TR severity was predictive for poor prognosis, especially in the FMR-subgroup [1-year survival: 92.9% vs. 78.3%, p = 0.025; HR for death at 1-year follow-up 3.31 (95% CI 1.15–9.58), p = 0.027]. While BNP levels decreased in both subgroups, TR reduction was associated with improved symptomatic benefit (NYHA-class-reduction 78.6 vs. 65.9%, p = 0.021). Conclusion: In this large study, both, severe TR at baseline as well as missing secondary reduction were predictive for impaired long-term prognosis, especially in patients with FMR etiology. TR reduction was associated with increased symptomatic benefit. Graphic