Atrial Functional Mitral Regurgitation

This study is a prospective, randomized, parallel-control, open-label, multicenter clinical trial. Eligible subjects will be randomized in a 1:1 ratio to the Device group (Interventional group) or to no Device group (Control Group). The objective is to identify the safety and effectiveness of the TEER for the treatment of moderate-to-severe (3+) or severe (4+) atrial functional mitral regurgitation (aFMR) in patients who are symptomatic despite maximally tolerated guideline directed medical therapy.

The goal of this clinical trial is to learn whether valsartan can slow the progression of atrial functional mitral regurgitation (AFMR) in adults with preserved left ventricular ejection fraction. The study will also evaluate the safety and tolerability of valsartan in this population. The main questions it aims to answer are: * Does treatment with valsartan reduce the progression of atrial functional mitral regurgitation compared with placebo? * Does valsartan have favorable effects on mitral valve leaflet remodeling and related cardiac structure and function? * Is valsartan safe and well tolerated in patients with atrial functional mitral regurgitation who do not currently require angiotensin-converting enzyme inhibitors or angiotensin receptor blockers? Researchers will compare valsartan to a placebo (a look-alike substance with no active drug) to see if valsartan reduces the progression of atrial functional mitral regurgitation and improves clinical and imaging outcomes. Participants will: * Take valsartan or placebo twice daily for 12 months, with dose adjustments based on blood pressure, kidney function, and tolerance * Undergo 3D echocardiography at baseline, 6 months, and 12 months * Complete a 6-minute walk test at baseline and 12 months * Complete the Kansas City Cardiomyopathy Questionnaire (KCCQ) at baseline, 6 months, and 12 months * Undergo 24-hour ambulatory blood pressure monitoring at 1 month * Have regular safety monitoring, including phone follow-up at 7 days, blood tests at 1 month, and blood pressure checks after dose adjustments

This trial is a randomized study for patients with significant atrial functional mitral regurgitation (AFMR) and atrial fibrillation (AF). The composite endpoint of all-cause mortality, cardiovascular-related hospitalizations, AF recurrence, and quality of life improvement is hypothesized to be superior with the combination of transcatheter edge-to-edge repair (TEER) and catheter ablation, compared with catheter ablation alone.

Atrial fibrillation (AF) leads to atrial functional mitral regurgitation (MR) through mechanisms including mitral annular dilatation, systolic leaflet motion distance alteration, and contractility decrease. Compared with primary MR, atrial functional MR due to AF and other diseases tends to have a worse prognosis, with a higher risk of death and heart failure hospitalization. MR and AF co-exist and exacerbate left atrial dysfunction, further causing worse cardiac dysfunction, valvular regurgitation, and aggravating prognosis. The best therapy for secondary MR is unclear because MR is only one component of the disease, and restoration of mitral valve competence is not curative. Catheter ablation improves symptoms and cardiac function in patients with AF, reduces risks of AF recurrence and hospitalization, as well as increases quality of life. For patients with AF combined with functional moderate-to-severe MR, previous observational studies have found that the severity of MR significantly reduced after taking catheter ablation to restore sinus rhythm. We hypothesized that catheter ablation would significantly improve the severity of MR in patients with severe atrial functional MR combined with persistent AF compared with drug therapy alone.

This investigator-initiated, multicenter, international, retrospective registry aims to investigate outcomes of patients with atrial functional mitral regurgitation, as treated in clinical routine.

To evaluate the improvement of mitral regurgitation after catheter ablation of atrial fibrillation or regular drug therapy in atrial fibrillation patients combined with atrial functional mitral regurgitation.