Persistent atrial fibrillation and risk factors for recurrence at 3 and 12 months after interventional therapy

Background: This study examined the early recurrence (within the first 3 months) of atrial fibrillation (AF) in patients with persistent AF, focusing on the effective refractory period (ERP) of the left atrium and pulmonary veins and clinical and laboratory comorbidities. Furthermore, the study evaluated outcomes 12 months after treatment. Materials and methods: Sixty patients with persistent AF refractory to antiarrhythmic therapy were included. Each patient underwent ERP assessment of the left atrium and pulmonary veins, followed by radiofrequency antral isolation of the pulmonary vein ostia. The patients were grouped into two based on ERP values: group 1, patients with average ERP values of the left atrium and pulmonary veins ≥ 240 ms and group 2, those with average ERP values 240 ms. The incidence of early AF recurrence was assessed within the first 3 months based on ERP values, and the efficacy of catheter ablation was evaluated at 12 months. Results: No significant differences were found in instrumental parameters (echocardiography and multislice computed tomography), laboratory findings (serum creatinine and glomerular filtration rate), and comorbidities between patients with and without early AF recurrence. However, the risk of early AF recurrence in group 2 was 6 times higher compared to that in group 1 (p = 0.04), and the risk of recurrence within 12 months after catheter ablation was 4 times higher (p = 0.02). Conclusions: These findings indicate that an ERP of the left atrium and pulmonary veins below 240 ms may predict early AF recurrence (p = 0.04), AF recurrence within 12 months (p = 0.03), and the need for repeated ablation (p = 0.02). Clinical and laboratory comorbidities were not found to be significant predictors of early AF recurrence following interventional therapy in patients with persistent AF.