Abstract 4370097: Long-term Outcomes of Anticoagulation Guided by an Implantable Loop Recorder Following Catheter Ablation of Atrial Fibrillation

Background: Continued oral anticoagulation (OAC) following catheter ablation of atrial fibrillation (AF), even if successful in patients (pts) at a high risk of stroke, is recommended by the guidelines. Current implantable loop recorders (ILRs) can automatically detect AF and alert for it daily. Thus, a “pill-in-the-pocket” approach in these pts has been advocated. Objective: To determine outcomes of post AF ablation pts in whom long-term OAC use was guided by ILRs. Methods: We enrolled consecutive pts with AF and CHA 2 DS 2 -VASc ≥ 1 who had undergone AF ablation and had an ILR. Pts with prior stroke were mostly excluded. Daily ECG data was adjudicated. Three months post-ablation, OAC was stopped in all pts confirmed free of AF and not restarted unless there was AF recurrence. The cohort was then categorized into three groups: anticoagulation remained discontinued (ACDC), anticoagulation discontinued but then restarted (ACDC + Restart) due to AF recurrence, and anticoagulated continuously (AC) because of continued AF. Results: The study cohort included 273 pts (67 ± 9 years, 62% male, 2.6 ± 1.3 CHA 2 DS 2 -VASc), followed for a mean of 1469 ± 837 days, 164 (60%) who stopped the AC at 181 [99;325] days. During follow-up, 5 (1.8%) pts experienced a TIA or stroke: 3 (1.8%) off AC and 2 (1.8%) on AC (p – 0.68). OAC remained permanently off in 101 (37%) pts; was restarted in 63 (23%) pts and was never stopped in 109 (40%) pts (Figure). Pts in ACDC were younger, had lower CHA 2 DS 2 -VASc score, had smaller left atrial diameter and lower BMI (Table). Conclusions: Our data show that an ILR guided strategy post-AF ablation allowed 37% of pts to remain off OAC during more than 4 years of follow-up. During this time, there was a low incidence of TIA/Stroke (0.45%/year). While longer-term follow-up data are needed, it appears that it may be possible to use this strategy in certain post AF ablation pts.