Patent Foramen Ovale Closure for Primary Prevention of Stroke.

Background: Patent foramen ovale (PFO) is common and has been associated with cryptogenic stroke; however, evidence supporting PFO closure for primary prevention of stroke remains limited. Current guidelines discourage routine closure in patients without prior cerebrovascular events, due to insufficient data. Methods: We conducted a retrospective cohort study using the TriNetX Network, including adults diagnosed with PFO between 2014 and 2022 without documented prior ischemic stroke or atrial fibrillation and/or flutter. Patients were stratified based on having undergone transcatheter PFO closure vs not having done so. Propensity-score matching was performed using demographic characteristics, comorbidities, medications, and laboratory values. Outcomes were assessed up to 1 year following the index event. The primary outcome was ischemic stroke. Secondary outcomes included all-cause mortality, hospitalization, atrial fibrillation, cardiac arrest, and sleep apnea. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were calculated. Results: A total of 3398 patients were included in each cohort, with comparable baseline characteristics and follow-up duration. PFO closure was associated with a significantly lower incidence of ischemic stroke compared with no closure (3.5% vs 6.4%; aOR 0.53, 95% CI 0.35-0.82). All-cause hospitalization was also reduced in the closure cohort (15.5% vs 28.6%; aOR 0.46, 95% CI 0.41-0.52). New-onset atrial fibrillation occurred more frequently after PFO closure (1.1% vs 0.4%; aOR 3.09, 95% CI 1.72-5.55), with no significant differences in mortality. Conclusions: In this large cohort without documented prior stroke, PFO closure was associated with lower stroke incidence but higher atrial fibrillation risk. Prospective studies are needed before extending closure indications to primary prevention populations.