Table 2. Summaries of the studies reporting the results of stopping OACs after AF ablations.
| Author [year] | Patient number and characteristics | Use of anticoagulants after catheter ablation | Event rate | Main findings | Limitations |
|---|---|---|---|---|---|
| Oral et al. [2006] (9) | Paroxysmal AF: 490 | Warfarin was used for 3 months after catheter ablation. Among 522 patients who remained in sinus rhythm, warfarin was discontinued in 79% of patients without risk factors and in 68% of patients with ≥1 risk factor of stroke after 3 months | Rate of TEs: 0.9% within 30 days of ablation procedure; 0.3% beyond 30 days after the procedure | Discontinuation of warfarin appears to be safe after successful ablation | The authors continued OATs for patients with an age of >65 years or a prior history of stroke/TIA after successful ablation |
| Chronic AF: 265 | |||||
| 55±11 years | |||||
| 56% had ≥1 risk factor for stroke | |||||
| Themistoclakis et al. [2010] (31) | A total of 3,355 patients (60% paroxysmal AF) | Off-OAC group: 2,692 patients discontinued OACs 3 to 6 months after ablation | During follow-up (mean 28±13 vs. 24±15 months), 2 (0.07%) off-OAC group patients and 3 (0.45%) on-OAC group patients had an ischemic stroke (P=0.06) A major hemorrhage was observed in 1 (0.04%) off-OAC group patient and 13 (2%) on-OAC group patients (P<0.0001) |
The risk-benefit ratio favored the suspension of OACs after successful AF ablation even in patients at moderate-high risk of TE | The authors kept their patients on OACs when any arrhythmic recurrences, left atrial dysfunction, or severe PV stenosis were observed |
| 57±11 years | On-OAC group: 663 patients remained on OACs after 3 to 6 months post ablation | ||||
| CHADS2 score: 0 in 53%, 1 in 29%, ≥2 in 18% | |||||
| Yagishita et al. [2011] (12) | A total of 524 patients (16% had a CHADS2 score of >2) underwent AF ablation and were followed up for at least 24 months | Warfarin was discontinued in 400 (93%) of 429 patients without AF recurrence | None of the patients without AF recurrence suffered from TE events, where 3 of 95 patients (3%) with AF recurrence did (P<0.001) | Neither a TE nor hemorrhagic events occurred in patients who were AF-free and off warfarin | The authors continued warfarin in 29 patients without an AF recurrence due to the concern about undetected AF recurrences |
OACs, oral anticoagulants; AF, atrial fibrillation; TE, thromboembolic; TIA, transient ischemic attack; PV, pulmonary vein.