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Updated: Jan 26, 2026

Closure of a Patent Foramen Ovale PFO: An Intervention Sequence
Published on: December 23, 2022
Device Closure of Patent Foramen Ovale for Cryptogenic Stroke: Patient Selection and Outcomes According to New
Adam M Carroll1, John D Carroll2,3
1University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO, 80045, USA.
Purpose Of Review:
This review summarizes the most recent randomized clinical trials that studied the role of device-mediated patent foramen ovale (PFO) closure in patients after an ischemic stroke presumed to have been caused by a paradoxical embolism.
Recent Findings:
Three major randomized trials published in 2017 studied the strategy of using PFO closure for secondary prevention in patients between the ages of 18 and 60 who presented with an index stroke having characteristics of an embolic mechanism. All patients had a PFO that potentially could have enabled paradoxical embolism and other causes of stroke were excluded by a thorough neurologic and cardiac evaluation. Patients were randomized to PFO closure versus medical therapy alone using a variety of guideline-recommended medications. After multiple years of follow-up, all three trials showed superiority in the device arm versus the medical arm with a relative risk reduction of recurrent stroke from 46 to 100% and an absolute recurrent stroke reduction from 0.49 to 1.32% per year. Complications related to the procedure and the device were infrequent and mostly transient. These results have transformed the care of these patients, lead to FDA approval of two PFO closure devices, and started the process of updating guidelines. Patient selection is critically important since the presence of a PFO may be incidental. Therefore, both a neurologist and a cardiologist, who can also perform this procedure safely and effectively, should complete the initial evaluation and discuss their findings and recommendations with the patient as part of a shared decision-making process. There are remaining questions regarding how these trial results relate to older patients, patients with overt venothrombotic disease, and those with thrombophilia.
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