The Incidence of Atrial Fibrillation After Percutaneous Patent Foramen Ovale Closure Detected by Implantable Loop Recorders.

Background: Patent foramen ovale (PFO) is seen in 25% of the general population but in up to 50% of patients ≤60 years old with cryptogenic strokes. Trials have shown that PFO closure vs medical therapy reduces the risk of future strokes. PFO closure may cause atrial fibrillation (AF), with prior trials reporting an incidence of 2% to 11.9%. However, the true incidence of AF after PFO closure is unknown due to limitations in prior studies for long-term monitoring. Methods: This is a retrospective observational study at a single center. Patients who underwent PFO closure and had an implantable loop recorder prior to PFO closure were included. The final review included 38 patients who had at least 2 months of implantable loop recorder data post-PFO closure. Results: Ten out of 38 (26%) patients developed AF post-PFO closure. The median time to the first episode of AF was 3.95 weeks, with 40% having their first AF episode after 3 months. Median duration of AF episodes was 1 hour. One hundred percent had spontaneous termination of AF. Of the AF patients, 70% were started on oral anticoagulant therapy. Conclusions: Our review shows a higher incidence of AF post-PFO closure as compared with most reported prior studies. We recommend larger prospective studies to explore the true incidence of AF post-PFO closure, its clinical impact, and subsequent stroke risk.