Incidence of atrial fibrillation in cryptogenic stroke with patent foramen ovale closure: protocol for the prospective, observational PFO-AF study

INTRODUCTION: After closure of patent foramen ovale (PFO) due to stroke, atrial fibrillation (AF) occurs in up to one in five patients. However, data are sparse regarding the possible pre-existence of AF in these patients prior to PFO closure, and about recurrence of AF in the long term after the procedure. No prospective study to date has investigated these topics in patients with implanted cardiac monitor (ICM). The PFO-AF study (registered with ClinicalTrials.gov under the number NCT04926142) will investigate the incidence of AF occurring within 2 months after percutaneous closure of PFO in patients with prior stroke. AF will be identified using systematic ICM. Secondary objectives are to assess incidence and burden of AF in the 2 months prior to, and up to 2 years after PFO closure. METHODS AND ANALYSIS: Prospective, multicentre, observational study including 250 patients with an indication for PFO closure after stroke, as decided by interdisciplinary meetings with cardiologists and neurologists. Patients will undergo implantation of a Reveal Linq device (Medtronic). Percutaneous PFO closure will be performed 2 months after device implantation. Follow-up will include consultation, ECG and reading of ICM data at 2, 12 and 24 months after PFO closure. The primary endpoint is occurrence of AF at 2 months, defined as an episode of AF or atrial tachycardia/flutter lasting at least 30 s, and recorded by the ICM and/or any AF or atrial tachycardia/flutter documented on ECG during the first 2 months of follow-up. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee ‘Comité de Protection des Personnes (CPP) Sud-Méditerranéen III’ on 2 June 2021 and registered with ClinicalTrials.gov (NCT04926142). Findings will be presented in national and international congresses and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04926142.