Role of atrial fibrillation ablation in the management of atrial mitral and atrial tricuspid regurgitation: a case report.

Background: Atrial fibrillation (AF) and functional mitral regurgitation (FMR) frequently coexist. Surgical treatment or transcatheter edge-to-edge repair is the standard of care for severe FMR. In patients with atrial FMR (aFMR), atrial fibrillation is an important precipitating factor. Since catheter ablation (CA) is a safe and effective treatment of AF, it has been suggested that it may decrease the severity of aFMR. However, data are scarce and the mechanisms of aFMR improvement are not completely understood.

Case summary: We describe a case of an 86-year-old female with a history of AF and previous pulmonary vein isolation presenting with symptoms of acutely decompensated heart failure and recurrence of atrial flutter. Her echocardiography demonstrated non-dilated left ventricle with a normal ejection fraction, left atrial (LA) dilatation, severe FMR, and tricuspid regurgitation (TR). Due to failed electrical cardioversion and amiodarone intolerance, a successful catheter ablation of a LA flutter was performed. Electro-anatomical mapping revealed extensive LA low-voltage areas. During the follow-up of 18 months, the patient remained in sinus rhythm, and the FMR improved to MR II (effective regurgitant orifice area of 9 mm² and regurgitant volume of 18 mL); no improvement of the TR occurred.

Discussion: Catheter ablation can restore sinus rhythm, decrease LA volume, and improve the severity of atrial FMR. Reverse LA electrical remodelling plays a minor role in the amelioration of MR. Lack of improvement of the TR suggests a different mechanism of TR.