Data from the REDUCE, CLOSE, and RESPECT trials, published in the New England Journal of Medicine, showed that closing a patent foramen ovale with a percutaneous closure device can reduce the risk of ischemic stroke in patients who have already had a cryptogenic stroke. Observers believe these trials showed a benefit of PFO closure in this population after previous trials failed to show a benefit largely because they did a better job of only selecting patients most likely to benefit.

REDUCE is the first trial of patent foramen ovale closure device to show statistically significant reduction in stroke recurrence in its primary intent-to-treat analysis. The results, presented at the European Stroke Organisation Conference in Prague, will support Gore's application for Cardioform to the US FDA by the end of the year.

FDA's Circulatory System Devices Panel said that St. Jude's Amplatzer PFO closure device has benefits that outweigh risks to prevent recurrent stroke in a select group of patients on an 11-5 vote, despite having missed its primary endpoint in the pivotal RESPECT trial.

St. Jude won a May panel date for its Amplatzer patent foreman ovale occluder PMA, seeking approval to prevent recurrent stroke. It's been a challenging path to this point after the firm's pivotal RESPECT trial did not meet its primary endpoint in 2012.