[Effect of radiofrequency ablation on improving cardiac structure and function in patients with atrial fibrillation and functional mitral regurgitation].

<b>Objective:</b> Exploring the effect of radiofrequency ablation treatment to restore sinus rhythm on the improvement of functional mitral regurgitation (FMR) and cardiac structure in patients with atrial fibrillation combined with moderate or severe FMR, compared with drug therapy alone. <b>Methods:</b> This retrospective cohort study consecutively enrolled patients diagnosed with persistent atrial fibrillation and moderate or severe FMR who were admitted to the Third Affiliated Hospital of Sun Yat-sen University from January 2019 to December 2021. Forty-eight patients who were treated with radiofrequency ablation and maintained sinus rhythm were enrolled in the ablation group, and 63 patients who were treated with medication alone during the same period were in the medicine group. Patients in the ablation group and medicine group were matched in a 1∶1 ratio using a propensity score, and 41 patients were finally included in each of the 2 groups. All patients reexamined echocardiography after 3-month of treatment. The proportion of patients with FMR improvement and the differences in changes of cardiac structural and functional parameters were compared between groups. <b>Results:</b> After propensity score matching, the ablation group was aged (69.3±7.1) years with 21 males (51.2%) and the medicine group was aged (71.3±9.4) years with 21 males (51.2%). The echocardiography after 3-month of treatment showed the rate of FMR improvement was significantly higher in the ablation group than in the medicine group (19 (46.3%) vs. 33 (80.5%), <i>P</i><0.001), and patients in the ablation group showed a significant decrease in FMR extent (Δmitral regurgitation area: (-1.30±2.64) cm² vs. (-3.55±2.50) cm², <i>P</i><0.001), left atrial size (Δleft atrial diameter: (-0.17±3.78) mm vs. (-2.46±4.01) mm, <i>P</i>=0.009) and E/e' (ΔE/e':-2.54±7.34 vs.-6.34±7.08, <i>P</i>=0.021) compared with the medicine group. There was also a significant decrease in left ventricular size (Δleft ventricular end diastolic diameter: (-3.12±6.62) mm vs. (-0.73±3.62) mm, <i>P</i>=0.046) and significant increase in left ventricular ejection fraction (Δleft ventricular ejection fraction: (2.73±9.69) % vs. (-0.93±5.41) %, <i>P</i>=0.038) in ablation group. <b>Conclusion:</b> Performing radiofrequency ablation to restore sinus rhythm can effectively reduce the severity of mitral regurgitation and improve left atrial and left ventricular remodeling and cardiac function in patients with atrial fibrillation and FMR.