Background With the growing prevalence of atrial fibrillation (AF), atrial functional mitral regurgitation (AFMR) combined with AF is expected to become a common clinical issue. We have summarized various surgical treatment strategies based on the degree of mitral regurgitation (MR) alongside rhythm control therapy for patients with AFMR and AF. Methods This retrospective study included 145 patients with AF and MR from January 2017 to January 2023. 33 patients with AF and moderate AFMR were designated as the moderate atrial regurgitation (MAR) group. 56 patients with AF and severe AFMR were designated as the severe atrial regurgitation (SAR) group. The remaining 56 patients with AF and severe primary MR were designated as the severe primary regurgitation (SPR) group. All patients in the MAR group underwent thoracoscopic AF procedure via a unilateral approach. Patients in the SAR and SPR groups underwent mitral valvuloplasty plus the Cox Maze IV procedure (CMP IV). Descriptive characteristics and outcomes were analysed. Results Twenty-three patients maintained sinus rhythm (SR) following thoracoscopic AF procedure in the MAR group at average 2.6±1.1 years follow-up. The degree of regurgitation improved in 26 patients, remained unchanged in 6 patients, and worsened in 1 patient. SR maintenance benefits MR reduction (P<0.0001) compared to the non-SR patients. There was no significant difference in the rate of SR maintenance following mitral valvuloplasty plus CMP IV between SAR (43 patients, 79.6%) and SPR (49 patients, 87.5%) groups. At the last follow-up, echocardiography in the SAR group showed 47 cases with no mitral regurgitation, 4 cases with mild regurgitation, and 1 case with moderate regurgitation. The left atrial diameter in the SAR group remained larger than in the SPR group (P<0.001). Conclusions Rhythm control therapy is the cornerstone treatment for AFMR patients with AF. Thoracoscopic AF procedure is effective and minimally invasive for moderate AFMR patients with AF. For severe AFMR patients with AF, we recommend CMP IV plus mitral valvuloplasty for safety and effectiveness.

The authors have declared no competing interest.

The work was sponsored by National Natural Science Foundation of China (grant number: 82170313)

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This study has been approved by the Medical Ethics Committee of Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, and informed consent was obtained from all participants.

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