CARDIAC REMODELING AND OUTCOME AFTER SURGICAL INTERVENTION FOR ATRIAL FUNCTIONAL MITRAL REGURGITATION

Abstract The atrial functional mitral regurgitation refers to a newly recognized disease entity in which mitral regurgitation occurs secondary to left atrial disease, without left ventricular dilatation and intrinsic mitral valve disease. To better define this new entity and understand the benefits of surgery in patients with severe regurgitation, we conducted an observational analysis on 28 subjects with atrial functional mitral regurgitation who underwent surgical treatment between February 2020 and December 2022, at the Cardio Surgery Department of the “San Carlo” Hospital in Potenza. Twenty–eight subjects (11 males, 39.3%), mean age ± standard deviation 72.7 ± 8.4 years, who underwent surgical correction (mitral annuloplasty and tricuspid ring annuloplasty when needed) for significant atrial functional mitral regurgitation, sometimes associated with significant tricuspid insufficiency, were evaluated. No surgical treatment of atrial fibrillation has been performed. Subjects were assessed at enrollment and at one–year follow–up. We evaluated clinical and echocardiographic parameters. There was no in–hospital mortality. Mitral valve repair determined a reverse remodeling of the left ventricle and left atrium, with a significant reduction of the end–diastolic volume of the left ventricle [110 ml (95–148 ml)] vs. (55 ml (48–59 ml), z: –0,7, p<0.001]) and of left atrial volume [83.5 ml (63.2–96.5 ml) vs. 63 ml (45.5–78.7 ml), z: –3.2, p: <0.01]. We also observed a significant reduction of the estimated pressure in the pulmonary artery, an expression of reduced pressures in the left ventricle that affect the pulmonary circulation [35 mmHg (30–43) vs. 25 (22–32.7), z: –3.9, p< 0.001]. Results were not altered by the presence or absence of atrial fibrillation. The overall 1–year survival rates were 100% and all the patients recovered to NYHA functional class I/II at the follow up (z: –6, p < 0.001). Our results suggest that mitral valve repair for atrial functional mitral regurgitation is safe and effective. It improves heart failure symptoms and results in reverse–remodeling of both the left atrium and left ventricle. The presence of atrial fibrillation did not alter the outcome.