Managing stroke prevention in atrial fibrillation becomes complex when bleeding risk limits long-term anticoagulation. The American Heart Journal has detailed the ongoing CLOSURE-AF trial, which will determine whether LAA closure offers a safer and equally effective alternative to medical therapy in this high-risk population.

The prospective, multicenter, randomized CLOSURE-AF trial compares percutaneous LAA closure with best medical care, including non–vitamin K antagonist oral anticoagulants (NOACs) when appropriate. The study enrolled 912 adults with atrial fibrillation and elevated stroke risk scores (CHA₂DS₂-VASc ≥2) who also had a history of bleeding or a HAS-BLED score of 3 or higher.

Participants were randomly assigned to receive either catheter-based LAA closure or best medical therapy. The primary outcome will measure the time to first occurrence of stroke, systemic embolism, cardiovascular or unexplained death, or major bleeding. Secondary outcomes include total mortality and the individual components of the composite endpoint.

With enrollment completed in April 2025, the results are expected to clarify whether LAA closure can match or surpass standard therapy in balancing stroke prevention and bleeding safety in high-risk atrial fibrillation.