An increase in stroke risk factors over time without arrhythmia recurrence does not require restarting anticoagulation in low-risk atrial fibrillation patients after successful ablation. (RESTART-AF)

Background Oral anticoagulation (OAC) is stopped after successful pulmonary vein isolation (PVI) in atrial fibrillation (AF) patients with a CHA2DS2-VA score of 0 or 1. The CHA2DS2-VA score will increase over time and its impact on the stroke risk in the absence of AF recurrence is currently unclear. Restarting OAC solely based on an increase in stroke risk factors without AF recurrence is not advocated at the present time. Purpose To assess the impact of the CHA2DS2-VA score evolution over time on the stroke risk in patients without documented AF recurrence after PVI. Methods We analyzed 338 CHA2DS2-VA = 0 or 1 AF patients (Age 59 (IQR 53-64), 69% males) where OAC was stopped after successful PVI. During a median follow-up of 6.7 years (IQR 6.2-7.1), evolution in CHA2DS2-VA score, occurrence of stroke or systemic embolism and documented AF recurrence were sampled. Results At least one new stroke risk factor developed in 230 patients (68%): 125 (37%), 87(26%), 16 (5%) and 2 (1%) of patients developed respectively 1, 2, 3 or 4 additional risk factors. Overall, 158 of patients (47%) reached the CHA2DS2-VA score threshold for OAC of ≥2 at the end of follow-up. Risk factors consisted of age in 171(50%), arterial hypertension in 116 (34%) or vascular disease in 71 (21%) patients. No stroke or systemic embolism occurred during follow-up. Seventy-eight patients (23%) had recurrent AF and were restarted on OAC. A CHA2DS2-VA score increase over time was associated with AF recurrence and subsequent reinitiation of OAC (HR 1.30 per 1-point increase, 95% CI 1.02–1.649, p=0.036). Conclusion Stroke risk appears not to be influenced with the sole development of new risk factors in patients without AF recurrence after successful PVI. Restarting of OAC based on CHA2DS2-VA score increase without AF recurrence is not needed. However, additional risk factors increase AF recurrence risk for and hence trigger reinitiation of OAC.