Impact of thermal ablation methods on sinus rhythm maintenance after mitral valve surgery in patients with atrial fibrillation.

Background: This study aimed to compare the effects of cryoablation (CrA) and radiofrequency ablation (RFA) in achieving conversion from atrial fibrillation (AF) to sinus rhythm (SR) and to evaluate factors associated with postoperative AF recurrence in patients undergoing mitral valve surgery. Methods: A total of 88 patients diagnosed with AF who underwent mitral valve replacement combined with the Cox-Maze IV procedure between 2014 and 2020 were included in the study. CrA was performed in 48 patients (54.5%), while RFA was applied in 40 patients (45.5%). Patients were grouped according to the ablation modality used and the presence or absence of postoperative AF recurrence. All patients had AF for at least six months preoperatively, as confirmed by Holter monitoring.Associations between AF recurrence and clinical parameters, including left ventricular ejection fraction (LVEF), left atrial diameter (LAD), and body mass index (BMI), and comorbidities, were evaluated. Results: The mean follow-up duration was 6 months, with no mortality observed during this period. At six months postoperatively, SR was maintained in 70% (n=28) of patients in the RFA group and 79% (n=38) in the CrA group, with no statistically significant difference between the two groups (p>0.05). AF recurrence was significantly associated with increased LAD (p=0.01), presence of chronic obstructive pulmonary disease (p=0.007), obesity (BMI ≥30 kg/m2; p<0.001), and reduced LVEF (p<0.001). Conclusion: Both CrA and RFA-as alternative energy sources-were found to be effective in converting AF to SR. Additionally, our study revealed that the demographic and clinical characteristics had an influence on AF recurrence.