Patients with atrial fibrillation (AF) have an increased risk of stroke. This risk can be reduced using treatment with oral anticoagulants. To date it is unknown if elimination or substantial reduction of AF with an ablation procedure also reduces the risk of stroke associated with AF.  If it does reduce the stroke risk, then patients who have a successful ablation may not need to continue on life-long oral anticoagulant therapy. However, this benefit has to be weighed against the risk of ongoing stroke despite significant AF reduction.

The OCEAN trial is a prospective, open-label randomized controlled phase 4 trial that will compare medical approaches for stroke prevention in people who have AF but have undergone a successful ablation to eliminate or substantially reduce the arrhythmia. This trial will compare a strategy of oral anticoagulant therapy with rivaroxaban to an aspirin per day after successful AF ablation. The primary outcome will be a composite of stroke, systemic embolism and silent cerebral infarction as defined by cerebral magnetic resonance imaging.

Over 1500 patients with a moderate risk of stroke will be enrolled in seven countries.