Mitral regurgitation evolution after transcatheter tricuspid valve interventions - A sub-analysis of the TriValve registry

Aims: Transcatheter tricuspid valve interventions (TTVI) are increasingly used to treat patients with significant tricuspid regurgitation (TR). The evolution of concurrent mitral regurgitation (MR) severity after TTVI is currently unknown and may be pivotal for clinical decision-making. The aim of this study was to assess the evolution of MR after TTVI and to identify predictors of MR worsening and improvement. Methods and results: This analysis is a substudy of the TriValve Registry, an international registry designed to collect data on TTVI. This substudy included all patients with echocardiographic data on MR evolution and excluded those with a concomitant tricuspid and mitral transcatheter valve intervention or with a history of mitral valve intervention. The co-primary outcomes were MR improvement and worsening at two timepoints: pre-discharge and 2-month follow-up. This analysis included 359 patients with severe TR, mostly (80%) treated with tricuspid transcatheter edge-to-edge repair (T-TEER). MR improvement was found in 106 (29.5%) and 99 (34%) patients, while MR worsening was observed in 34 (9.5%) and 33 (11%) patients at pre-discharge and 2-month follow-up, respectively. Annuloplasty and heterotopic replacement were associated with MR worsening. Independent predictors of MR improvement were: atrial fibrillation, T-TEER, acute procedural success, TR reduction, left ventricular end-diastolic diameter > 60 mm, and beta-blocker therapy. Patients with moderate-to-severe/severe MR following TTVI showed significantly higher death rates. Conclusion: MR degree variation is common after TTVI, with most cases showing improvement. Clinical and procedural characteristics may predict the MR evolution, in particular procedural success and T-TEER play key roles in MR outcomes. TTVI may be beneficial, even in the presence of functional MR.