Larger left atrial diameter and lower post-procedural CK-MB and cTnT levels were significant risk factors for atrial fibrillation recurrence at 1 year after cryoballoon ablation.
Cohort (n=204)
No
Larger left atrial diameter and lower post-procedural cardiac enzyme release are associated with a higher risk of atrial fibrillation recurrence after cryoballoon ablation for persistent AF, suggesting the presence of advanced atrial fibrosis.
Abstract Background Advances in medical technology have improved the durability of pulmonary vein isolation (PVI) by catheter ablation. As a result, an increasing number of cases have recurrent atrial fibrillation (AF) despite the absence of PV-left atrial (LA) electrical re-conduction. Objective To elucidate the mechanisms of AF recurrence by analyzing risk factors for recurrence after cryoballoon ablation (CBA) of persistent AF (PsAF) and electrophysiological findings in patients undergoing a second ablation. Methods Patients with PsAF who underwent CBA at our institution between September 2017 and February 2022 were included. Treatment consisted of PVI with a 28mm-CB and cavotricuspid isthmus (CTI) ablation with a radiofrequency catheter (RFC), additional right atrial-superior vena cava (SVC) isolation, and intra-LA treatment with RFC for treatment-resistant cases. Patients who remained in sinus rhythm without antiarrhythmic drugs (AADs) were included in the AF-suppressed group, and the remainder in the non-suppressed group. Age, sex, body mass index (BMI), left atrial diameter (LAD), and ejection fraction (EF) measured by echocardiography were selected as patient background, and total freezing time, creatine kinase-MB (CK-MB) and cardiac troponin T (cTnT) on the day after treatment were selected as treatment information. The risk of recurrence was statistically analyzed. In addition, the durability of PVI was assessed in all patients who underwent a second ablation. Results The total number of patients was 204, age 68.2±10.3years, sex: male 69.8%, BMI 24.9±4.1kg/m2, LAD and EF were 45.3±5.8mm and 62.9±11.5%, respectively. Ablation included 100% PVI, 87.3% CTI, 8.3% SVC isolation, and 0.5% LA block line creation. CB freezing time was 954±213seconds, CK-MB and cTnT were 30.23±14.9IU/L and 2.5±1.6ng/mL, respectively. After 1 year, 83.3% of the patients had suppressed AF without AADs, 8.3% with AADs, 3.4% had undergone a second ablation, and 4.9% remained in PsAF. At the end of the follow-up period (51.1±18.2months after the first ablation), 70.1% of the patients had AF suppressed by the first ablation alone, and 17.1% underwent a second ablation. Comparing the AF-suppressed and non-suppressed groups at 1 year, the risk of recurrence was LAD (44.9±5.89 vs. 47.1±4.69mm, p0.02), CK-MB (31.1±15.52 vs. 25.1±9.61IU/L, p0.01), cTnT (2.59±1.7 vs. 2.11±0.81ng/mL, p0.01), with no significant differences in other parameters. Analysis of electrophysiological findings in 35 patients who underwent a second ablation by February 2025 (time from first to second ablation: 23±16.6months) showed a PV reconduction rate of 7.6%. Conclusions LA dilatation and low CK-MB and cTnT levels after the procedure were risk factors for recurrence; the durability of PVI is sufficient, and most recurrent cases are thought to have pathological changes from PV foci to non-PV foci. In such cases, peri-PV myocardium is considered fibrotic and reduced before the first ablation.
Sakabe et al. (Sat,) conducted a cohort in Persistent atrial fibrillation (n=204). Cryoballoon ablation was evaluated on Atrial fibrillation recurrence at 1 year. Larger left atrial diameter and lower post-procedural CK-MB and cTnT levels were significant risk factors for atrial fibrillation recurrence at 1 year after cryoballoon ablation.