A Review of Evidence for Surgical Closure Versus Medical Therapy Alone in Preventing Recurrent Stroke in the Presence of a Patent Foramen Ovale.

Presented is a review of the evidence for surgical closure of a patent foramen ovale (PFO) vs. medical therapy alone in the prevention of recurrent stroke in those who have already suffered a cryptogenic stroke. Several trials that made this comparison were identified. Their methodologies and results were analysed in an attempt to make a unifying conclusion about whether surgical closure is beneficial and for which groups of patients. A literature search identified six significant trials conducted over the last two decades, which recruited a total of 3,750 participants aged 60 years or younger. Their methodologies, including inclusion and exclusion criteria, device choices, endpoint definitions and published results, were evaluated and compared. Early trials were unable to demonstrate a benefit from closure. Later trials found a significant benefit to closure. The later trials refined the inclusion and exclusion criteria to recruit more at-risk participants, specifically those with large atrial septal aneurysms (ASAs) and large shunts across the atrial septum. There were procedural concerns with all trials to varying degrees. Concerns included the open nature of the trials, vague inclusion/exclusion criteria, participants treated outside of their assigned designation, lack of adequate power and mid-trial changes to the defined outcome measures. It appears there is evidence in favour of PFO closure in the prevention of recurrent stroke in young patients with large ASAs and large shunts. PFO closure was associated with significantly higher rates of atrial fibrillation and serious procedure-related complications, so the relative risk and reward must be determined on a patient-to-patient basis. A decision should be made only after a thorough investigation, which is to include bubble echocardiography, long-term ECG/Holter monitoring and exclusion of non-PFO-related index strokes via a comprehensive search for alternate aetiologies.