Practice change on the horizon: Blood thinning after atrial fibrillation ablation reevaluated

After successful ablation of atrial fibrillation (AF), it was previously unclear whether patients still needed blood thinning (oral anticoagulation, OAC). Experts previously advised continuing blood thinning depending on the CHA₂DS₂-VASc score, even if atrial fibrillation no longer occurred.

Two recent studies now call this practice into question:

• The ALONE AF study examined 840 patients who had no atrial fibrillation for at least one year after ablation. Half of them stopped taking blood thinners, while the other half continued to take them. After two years, the rate of serious events (stroke or severe bleeding) was only 0.3% in the discontinuation group compared to 2.2% in the group that continued therapy. The higher number in the continued group was mainly caused by severe bleeding.
• The OCEAN study compared low-dose blood thinning (rivaroxaban 15 mg) with aspirin in 1,284 patients without atrial fibrillation after ablation. The rate of stroke and similar events was very low and comparable in both groups.

Although both studies are small, they collectively show that the risk of stroke is very low after successful atrial fibrillation ablation. This could mean that many patients will be able to safely stop taking blood thinners in the future.

However, individual assessment and consultation by the treating physicians remains essential.