Ablation With Transcatheter Edge-to-edge Repair for Atrial Functional Mitral Regurgitation and Atrial Fibrillation

Rationale:

The introduction of transcatheter edge-to-edge repair (TEER) for the treatment of functional mitral regurgitation (FMR) has led to a significant reduction in mortality and heart failure hospitalizations. However, the optimal timing and intervention for patients with atrial functional mitral regurgitation (AFMR) have not been evaluated in clinical trials. Published clinical trials, including COAPT, MITRA-FR, and RESHAPE-HF, did not classify functional mitral regurgitation according to ventricular or atrial origin. Concerns regarding the role of atrial fibrillation (AF) as a potential trigger of atrial dilatation and a consequence of atrial remodeling have led to recommendations for rhythm control in selected patients. Given the high incidence of AFMR among patients with persistent AF, successful ablation and maintenance of sinus rhythm may remain challenging. Therefore, concomitant TEER and catheter ablation are hypothesized to provide greater clinical benefit compared with catheter ablation alone.

Aim:

The purpose of this study is to evaluate the efficacy of TEER combined with catheter ablation in patients with significant AFMR and AF, focusing on clinical outcomes and atrial reverse remodeling.

Study design:

Patients with moderate-to-severe or severe AFMR and AF will be enrolled in a randomized, open-label, controlled study. Patients will be randomized in a 1:1 ratio to receive TEER combined with catheter ablation or catheter ablation alone. The study duration is anticipated to include 24 months of enrollment and 12 months of follow-up.

Inclusion criteria

• Age ≥ 18 years
• Left ventricular ejection fraction ≥ 50%
• Grading of MR: 3+ or 4+ (effective regurgitant orifice area≥30mm2, regurgitant volume ≥45ml)
• Valve morphology: MR originating from the mid portion of the valve; mitral valve area> 4 cm2; Length of posterior leaflet ≥10 mm; Sufficient leaflet tissue for mechanical coaptation: coaptation depth< 11 mm, coaptation length> 2 mm
• Rate control in suspected AF-induced cardiomyopathy (heart rate <80 bpm at rest and <110 bpm during exercise)
• Patients must be willing to comply with all follow-up requirements

Exclusion criteria

• Life expectancy< 1 year due to non-cardiac conditions
• Primary mitral regurgitation: valve abnormalities including leaflet tethering from LV dysfunction, intrinsic leaflet pathology (prolapse, flail, calcification, severe thickening), mitral annular calcification (either severe or <severe but extending into the leaflets), and/or any mixed pathology
• Active endocarditis of the mitral valve or rheumatic mitral valve disease
• Hypotension (systolic pressure < 90 mmHg) or requirement for inotropic support or mechanical hemodynamic support
• Severe tricuspid regurgitation; Physical evidence of right-sided congestive heart failure with echocardiographic evidence of severe right ventricular dysfunction; Fixed pulmonary artery systolic pressure> 70 mmHg
• Stroke/TIA, TAVR, CRT/ CRT-D/ ICD, cardiac intervention or surgery within 30 days before randomization
• Any prior MV surgery or transcatheter procedure
• Need for any cardiac surgery (other than for MV disease)
• Untreated clinically significant coronary artery disease
• Echocardiographic evidence of intracardiac thrombus
• Active infections requiring current antibiotic therapy
• Patients who cannot tolerate anti-platelet/anticoagulation agents/contrast media
• Pregnancy
• Any condition making it unlikely the patient will be able to complete all protocol procedures (including compliance with medical therapy) and follow-up visits
• Patient (or legal guardian) unable or unwilling to provide written informed consent before study enrollment