Comparison of Clinical Factors Between Recurrent and Non-recurrent Atrial Fibrillation Within One Year After Catheter Ablation by the Same Operators at a Regional Core Hospital in Japan.

Although catheter ablation has emerged as a cornerstone treatment for atrial fibrillation, recurrence after catheter ablation occurs in approximately 20%-40% of patients within one year. Moreover, advances in devices, evolving treatment strategies, and differences in operator proficiency are believed to significantly impact outcomes. Whether results from large-scale international clinical trials can be directly applied to clinical practice at a regional core hospital in Japan remains a matter of debate. Considering these backgrounds, this study aimed to compare the clinical factors between recurrent and non-recurrent groups after atrial fibrillation catheter ablation in a regional core hospital in Japan, using the same treatment approach conducted by the same operators. A total of 368 consecutive patients who had their first catheter ablation for atrial fibrillation at our hospital between January 2017 and March 2022 were divided into two groups: non-recurrent (n = 311) and recurrent (n = 57). The recurrent group had significantly longer procedure time (196 ± 64 vs. 174 ± 66 minutes; 95% confidence interval (CI) -0.05, 0.62; P = 0.021), more cases of early recurrence (42% vs. 13%; 95% CI 2.69, 8.82; P = 0.001), higher rates of long-standing persistent atrial fibrillation (39% vs. 22%; 95% CI 1.23, 4.08; P = 0.008), greater left atrial volume index (LAVI) (49.8 ± 19.7 vs. 37.7 ± 14.6 mL/m2; 95% CI 6.46, 17.56; P = 0.001), more patients with LAVI > 48.9 mL/m2 (51% vs. 22%; 95%CI 2.01, 6.83; P = 0.0001), and more patients with the estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2 (26% vs. 17%; 95% CI 0.98, 3.50; P = 0.046) than the non-recurrent group. Additional left atrial posterior wall isolation (LAPWI) for persistent and long-lasting persistent atrial fibrillation and cavotricuspid isthmus (CTI) ablation for long-lasting persistent atrial fibrillation were more frequent in the recurrent group (LAPWI for persistent atrial fibrillation (26% vs. 14%; 95% CI 1.14, 4.36; P = 0.029), LAPWI for long-lasting persistent atrial fibrillation (19% vs. 8%; 95% CI 1.21, 5.67; P = 0.023), CTI ablation for long-lasting persistent atrial fibrillation (30% vs. 13% cases; 95% CI 1.53, 5.11; P = 0.001)). Recurrent rate was significantly lower in cryoballoon than in radiofrequency catheter ablation in all types of atrial fibrillation. In the non-recurrent group, brain natriuretic peptide (BNP) and LAVI were significantly lower, and left ventricular ejection fraction (LVEF) was significantly higher at one year after catheter ablation than before (BNP: 63.5 ± 138.4 vs. 144.8 ± 168.3 pg/mL, P = 0.001, 95% CI -0.69, -0.37; LAVI: 31.3 ± 12.3vs. 37.1 ± 14.6 mL/m2, P = 0.001, 95% CI -0.69, -0.32; LVEF: 58.9 ± 7.7 vs. 55.2 ± 10.2 %, P = 0.001, 95% CI -0.25, -0.57). In the recurrent group, eGFR was significantly lower at one year after catheter ablation than before catheter ablation (53.3 ± 25.2 vs. 60.4 ± 24.1 mL/min/1.73 m2, P = 0.021, 95% CI -0.58, -0.05). In conclusion, in cases of catheter ablation for atrial fibrillation with significantly large LAVI (>49.8 mL/m2), eGFR < 45 mL/min/1.73 m2, extended procedure time, and early recurrence within 90 days after catheter ablation, recognizing the possibility of recurrence within one year after catheter ablation and conducting follow-up with a focus on renal protection may provide valuable insights for catheter ablation of atrial fibrillation in regional core hospitals in Japan.