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Updated: Jun 27, 2025

Closure of a Patent Foramen Ovale PFO: An Intervention Sequence
Published on: December 23, 2022
Patent Foramen Ovale Closure in Older Patients With Stroke: Patient Selection for Trial Feasibility
Andy Y Wang1, Peter M Rothwell1, Jason Nelson1
1From the Predictive Analytics and Comparative Effectiveness (PACE) Center (A.Y.W., J.N., B.K., D.K., D.M.K.), Institute for Clinical Research and Health Policy Studies (ICRHPS), Tufts Medical Center, Boston, MA; Department of Clinical Neurology (P.M.R., L.L., S.M., L.E.S.), Oxford University, London, United Kingdom; Comprehensive Stroke Center and Department of Neurology (J.L.S.), David Geffen School of Medicine, University of California, Los Angeles; Comprehensive Stroke Center (S.E.K.), Department of Neurology, University of Pennsylvania Medical Center, Philadelphia; Division of Cardiology (J.C.), Department of Medicine, University of Colorado Denver, Aurora; Université Paris Cité (J.-L.M.), Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266; GHU-Paris Psychiatrie et Neurosciences (J.-L.M.), Hôpital Sainte Anne; Département de Physiologie (G.D.), Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, Université Paris-Est Créteil (UPEC); Centre d'Investigations Cliniques (G.C.), Unité de Recherche Clinique, Hôpital Européen Georges-Pompidou, Assistance Publique-Hôpitaux de Paris, France; Department of Neurology (A.J.F.), Case Western Reserve University, Cleveland, OH; Division of Cardiovascular Medicine (H.C.H., B.L.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia; Department of Population Health (P.J.), University of Oxford, United Kingdom; Department of Neurology (J.S.K.), Gangneung Asan Hospital, University of Ulsan College of Medicine; Department of Cardiology (P.H.L.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea; Department of Neurology (H.P.M.), Bern University Hospital; Medical Faculty (B.M.), University of Bern, Switzerland; Cardiology Department (M.R.), Weill Cornell Medical Center, Cornell, NY; Division of Cardiology (R.W.S.), Department of Medicine, UTHealth/McGovern Medical School and The Memorial Hermann Heart and Vascular Institute, Houston, TX; Department of Cardiology (L.S.), Rigshospitalet, Copenhagen University Hospital, Denmark; Division of Cardiology (J.-K.S.), Asan Medical Center Heart Institute, University of Ulsan College of Medicine, Seoul, South Korea; BHF Cardiovascular Epidemiology Unit (E.D.A.), Department of Public Health and Primary Care, University of Cambridge; Victor Phillip Dahdaleh Heart and Lung Research Institute (E.D.A.), BHF Centre of Research Excellence, School of Clinical Medicine, Addenbrooke's Hospital; NIHR Blood and Transplant Research Unit in Donor Health and Behaviour (E.D.A.), all University of Cambridge; Health Data Research UK Cambridge (E.D.A.), Wellcome Genome Campus and University of Cambridge, Hinxton; University of Cambridge (E.D.A.), United Kingdom; Health Data Science Centre (E.D.A.), Human Technopole, Milan, Italy; Department of Medicine (M.D., S.H.), Columbia University, College of Physicians and Surgeons, New York, NY; Department of Neurology (M.S.V.E.), Vagelos College of Physicians and Surgeons, and Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY; Division of Neurology-Stroke Program (C.J.), Department of Medicine, University Health Network, Toronto Western Hospital, Ontario, Canada; Stroke Center (P.M.), Neurology Service, Lausanne University Hospital; Department of Neurology (M.-L.M., K.N.), University of Bern; Department of Neurology (M.-L.M.), Stadtspital Zürich; Department of Neurology and Stroke Centre (K.N.), Cantonal Hospital Aarau, Switzerland; Sapienza University of Rome (F.P.), Italy; Department of Neurology (J.S.), Hospital Universitari de Girona Dr Josep Trueta - IDIBGI, Spain; Department of Neurology and Stroke Center (C.W.), University Duisburg-Essen, Germany; Department of Public Health (D.K.), Erasmus University Medical Center, Rotterdam, the Netherlands; and Department of Neurology (D.E.T.), Tufts Medical Center/Tufts University School of Medicine, Boston, MA.
Background And Objectives:
Whether patent foramen ovale (PFO) closure benefits older patients with PFO and cryptogenic stroke is unknown because randomized controlled trials (RCTs) have predominantly enrolled patients younger than 60 years of age. Our objective was to estimate anticipated effects of PFO closure in older patients to predict the numbers needed to plan an RCT.
Methods:
Effectiveness estimates are derived from major observational studies (Risk of Paradoxical Embolism [RoPE] Study and Oxford Vascular Study, together referred to as the "RoPE-Ox" database) and all 6 major RCTs (Systematic, Collaborative, PFO Closure Evaluation [SCOPE] Consortium). To estimate stroke recurrence risk, observed outcomes were calculated for patients older than 60 years in the age-inclusive observational databases (n = 549). To estimate the reduction in the rate of recurrent stroke associated with PFO closure vs medical therapy based on the RoPE score and the presence of high-risk PFO features, a Cox proportional hazards regression model was developed on the RCT data in the SCOPE database (n = 3,740). These estimates were used to calculate sample sizes required for a future RCT.
Results:
Five-year risk of stroke recurrence using Kaplan-Meier estimates was 13.7 (95% CI 10.5-17.9) overall, 14.9% (95% CI 10.2-21.6) in those with high-risk PFO features. Predicted relative reduction in the event rate with PFO closure was 12.9% overall, 48.8% in those with a high-risk PFO feature. Using these estimates, enrolling all older patients with cryptogenic stroke and PFO would require much larger samples than those used for prior PFO closure trials, but selectively enrolling patients with high-risk PFO features would require totals of 630 patients for 90% power and 471 patients for 80% power, with an average of 5 years of follow-up.
Discussion:
Based on our projections, anticipated effect sizes in older patients with high-risk features make a trial in these subjects feasible. With lengthening life expectancy in almost all regions of the world, the utility of PFO closure in older adults is increasingly important to explore.

