Introduction: The increasing incidence of atrial arrhythmias in the elderly is mostly adjudicated to the age-dependent development of arrhythmic substrate. In the last years, catheter ablation has become a standard approach in treating atrial fibrillation (AF) and left and right atrial flutter (AFlutt). Data regarding safety and efficacy of AF/AFlut catheter ablation in patients over 80 years old remain scarce. This study reports our high-volume center experience regarding the safety and efficacy of catheter ablation in a large cohort of patients >80 years of age.

Methods: All consecutive patients >80 years undergoing de-novo-ablation for AF or AFlutt in our institution between 01/2016 and 12/2020 were included (n=293 patients; mean age 82.3 ± 2.27 years). Periprocedural safety and efficacy were assessed according to the arrhythmia (paroxysmal AF n=85, 29%; persistent AF n=146, 49.8%; left- and right- AFlutt n=62, 21.2%). For safety analysis, all complications requiring intervention or causing sequels occurring in the first 30 days after procedure were collected. For efficacy, arrhythmia-free survival was analysed after a blanking period of 6 weeks using repetitive 7 day Holter ECGs (typically every 3 months).

Results: Baseline characteristics are shown in table 1. A majority of patients suffered from multiple cardiovascular co-morbidities (CHA2DS2-VASc-score 4.45 ± 1.15). In accordance with recommendations, >30% were on reduced OAC. Acute procedural success defined as electrical isolation of all pulmonary veins (PV) and/or termination of AFlutt with demonstration of bidirectional block across the ablation line was achieved in all patients.
During a follow-up of 400 ± 446 days, 61.4% of patients remained in stable sinus rhythm after a mean of 1.56 ± 0.81 ablations (Figure 1). 32 (10.9%) Patients were lost to follow-up.
Single procedure outcome was significantly higher in paroxysmal AF compared to persistent AF (p = 0.03, s. Figure 1b).

In 17 patients (5.8%) a complication occurred: One patient suffered a pericardial tamponade during PVI followed by ablation of PVCs (LV and CS). Two patients suffered a stroke within a week after ablation of persistent AF and left AFlut. One TIA occurred after ablation of persistent AF. All patients had been under uninterrupted full-dose OAC and the strokes resolved without permanent handicap. Major groin complications occurred in 13 patients (4.4%). Acute arterial bleeding was treated by covered stent implant in 3 patients; thrombin injection of a pseudoaneurysm was necessary in 7 patients. Infection of the puncture site was observed in two patients and one patient suffered a large hematoma, which needed surgical treatment.
During the same hospital stay, 9 patients underwent pacemaker implantation due to underlying symptomatic sick-sinus-syndrome or pre-existing higher degree AV-block demasked in sinus rhythm, all of which were not procedure-related. 

 Conclusion: In this high-volume center experience, de novo catheter ablation of AF and AFluttin very old patients yielded low complication and encouraging success rates. In paroxysmal AF, ablation success rates seem to be similar to those in younger patients and are significantly higher than for persistent AF. After 1.56 ablation procedures, >60% of patients were free of arrhythmia, suggesting that the supposed atrial remodelling does not preclude a successful interventional treatment approach.