OCEAN: Understanding Atrial Fibrillation Recurrence and Long-term Management After Ablation

How do the OCEAN trial findings presented at EHRA 2026 advance our understanding of atrial fibrillation recurrence patterns following contemporary ablation strategies?

The findings are important because they have direct clinical relevance. The OCEAN trial is likely to support the discontinuation of anticoagulation in a lot of patients, so how these recurrences were managed is very important. What we observed was that recurrences occurred at a rate of approximately 6% per year. However, when recurrence did occur, episodes were generally brief, and most patients experienced only one or two recurrences. Importantly, these recurrences were not associated with an increased risk of stroke.

What were the most significant predictors of AF recurrence identified in OCEAN, and how might these inform risk stratification in clinical practice?

Two key positive predictors of atrial fibrillation recurrence were identified. The obvious one is the subtype of atrial fibrillation; persistent AF had a much higher risk of recurrence. The second predictor was weight, which was an extremely powerful factor. For every kilogram of extra weight, you had a 2% increase in the risk of recurrence. The third point to make is that the number of previous ablations did not predict recurrence, which suggests to us that most of these patients probably had durable pulmonary vein isolation (PVI) when they were randomized to start with, so a slightly different population from a lot of atrial fibrillation population studies.

How do the recurrence rates observed in OCEAN compare with prior landmark AF ablation trials, particularly in similar patient populations?

There aren’t many comparable trials because almost all atrial fibrillation trials evaluate outcomes after a single ablation procedure and then see how patients do. The OCEAN trial was very different in design. Patients could undergo any number of procedures, and only once procedures were successful were they randomized. So, it’s a very different population.

When writing the paper, we could only find one other somewhat similar population from a randomized controlled trial: the recently published long-term outcomes analysis from the ADVENT LTO study.² Remarkably, their data is almost the same as ours, a very similar recurrence rate. We had slightly higher, but their recurrent ablation rate it was very similar to ours.

Did the trial reveal any important insights regarding the timing and burden of recurrence that could influence post-procedural monitoring strategies?

Not directly, and that is an important point. The OCEAN trial was not designed to provide definitive guidance on optimal monitoring strategies because follow-up monitoring was largely left to physician discretion. Patients were reviewed annually for 3 years and questioned about symptoms suggestive of recurrence. Beyond that, additional rhythm monitoring was performed if the treating physician felt it was merited.

The key clinical point is, that even if you do stop oral anticoagulation in these patients, which may be reasonable in many of these patients, clinicians should avoid assuming that patients are cured indefinitely, some form of ongoing follow-up remains important. It could be a family doctor checking in with them every 6 months to see if they’re having recurrent problems.

Based on the OCEAN data, how should clinicians adapt their approach to long-term management and follow-up of patients undergoing AF ablation?

The OCEAN findings do not apply to all patients undergoing AF ablation. The study population was low to intermediate risk, with a mean CHA₂DS₂-VASc score of 2.2. So, the results should not be extrapolated to patients with very high stroke risk, such as those with a CHA₂DS₂-VASc score of 4 or more or patients with a previous embolic cerebrovascular accident. That’s really the key point. But otherwise, it really translates into clinical practice quite easily because it was a very practical monitoring strategy before entry into the trial. The monitoring strategy during the trial was also largely based on physician discretion. So, it’s not going to be that complex to translate it into clinical practice.