PFO closure in patients with cryptogenic stroke reduces recurrent stroke on MRI: REDUCE trial

A group of researchers from the U.S.A conducted the Gore REDUCE trial prospectively with baseline and follow-up magnetic resonance imaging (MRIs) for all subjects providing an objective measure of the effectiveness of closure.

The researchers performed blinded evaluations of the presence, location, and volume of new infarct on diffusion-weighted imaging of recurrent clinical stroke or new infarct (>3 mm) on T2/fluid-attenuated inversion recovery from baseline to follow-up MRI at 2 years, comparing closure to medical therapy alone. We also examined the effect of shunt size and the development of atrial fibrillation on infarct burden at follow-up.

The results of the study are as follows:

· At follow-up, a new clinical stroke or silent MRI infarct occurred in 18/383 (4.7%) patients who underwent closure and 19/177 (10.7%) medication-only patients.

· Clinical strokes were less common in closure patients compared with medically treated patients, 5 (1.3%) versus 12 (6.8%), while silent MRI infarcts were similar, 13 (3.4%) versus 7 (4.0%).

· There were no differences in number, volumes, and distribution of new infarct comparing closure patients to those treated with medication alone.

· There were also no differences of number, volumes, and distribution comparing silent infarcts to clinical strokes.

· Infarct burden was also similar for patients who developed atrial fibrillation and for those with large shunts.

Thus, the researchers concluded that the REDUCE trial demonstrates that patent foramen ovale closure prevents recurrent brain infarction based on the objective outcome of new infarcts on MRI. Only clinical strokes were reduced by closure while silent infarctions were similar between study arms, and there were no differences in infarct volume or location comparing silent infarcts to clinical strokes.

Reference:

Patent Foramen Ovale Closure Decreases the Incidence but Not the Size of New Brain Infarction on Magnetic Resonance Imaging: An Analysis of the REDUCE Trial by Messé S et. al published in the Stroke.

https://doi.org/10.1161/STROKEAHA.121.034451