Assessment of the renal function
In the present study, the eGFR calculated by 194 x age-0.287 x serum creatinine-1.094(x 0.739 for women)14 was evaluated as the renal function in all the subjects. In the ablation group, the eGFR within one month before the CA was defined as the baseline eGFR and evaluated three months and 12 months after the ablation. Among the patients who had recurrence of AF and underwent repeat ablation sessions, the post-ablation eGFR was evaluated after the last session. In the control group, the baseline eGFR was evaluated at the date of the AF documentation and evaluated three months and 12 months thereafter. Among the patients whose AF onset was unknown, the baseline eGFR was evaluated on the day the follow-up was started at the study institute. The ΔeGFR was defined as the change in the eGFR between baseline and 12 months and compared between the two groups. The difference in the ΔeGFR between the patients with paroxysmal AF (PAF) and non-PAF in the ablation group was also evaluated. Specifically, patients with an eGFR ≥90 mL/min/1.73 m2 were classified as a CKD stage G1, an eGFR of 60-89 mL/min/1.73 m2 as a CKD stage G2, an eGFR of 45-59 mL/min/1.73m2 as a CKD stage G3a, an eGFR of 30-44 mL/min/1.73 m2 as a CKD stage G3b, an eGFR of 15-29 mL/min/1.73 m2 as a CKD stage 4, and an eGFR <15 mL/min/1.73 m2 as a CKD stage G5.