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.
Patients were required to have moderate-to-severe or greater (≥3+) atrial functional mitral regurgitation assessed by transthoracic echocardiography within 14 days before randomization. Mitral regurgitation severity was graded by an echocardiography core-lab based on the American Society of Echocardiography criteria, specifically an effective regurgitant orifice area (EROA) ≥30 mm²
Age 18-80 years
Persistent atrial fibrillation diagnosed by electrocardiogram
Left ventricular ejection fraction ≥50% assessed by transthoracic echocardiography within 14 days before randomization(confirmed by the echocardiography core-lab)
paroxysmal atrial fibrillation, atrial fibrillation secondary to an apparently reversible cause, or with history of previous ablation;
primary mitral valve pathology, including calcification, sclerosis, prolapse, flail, tendon cable rupture, valve degeneration, infective endocarditis, rheumatic lesions, or ischemic lesions;
history of previous mitral valve surgery or transcatheter manipulation;
mitral valve orifice area <4 cm2;
Beijing Anzhen Hospital
Lead sponsor
Abbott
Collaborator