Because patent foramen ovale (PFO) represents a lesion which may be repaired a number of expert clinicians believe that mechanical closure should be the primary treatment modality for patients with PFO after cryptogenic stroke; interest has grown on percutaneous devices and in the last years there has been great technological advancement of percutaneous techniques for PFO closure. However, we should not close a PFO before establishing the evidence-based indications. At the same time, efforts to develop safer and more effective closure devices are under way. These devices include those with little or no metal component and those with biodegradable discs. Ideally, we should be able to identify at-risk patients before they sustain a stroke and to prevent stroke by closing the PFO with a device that should result in complete closure, be made of material that conforms to both sides of the septum, and have no risk of erosion, infection, arrhythmia, or thrombogenicity. Randomised trials comparing medical and percutaneous closure approaches are underway, but large patient enrollment is necessary because of the low event rate in the younger patients. Meanwhile, as the complication rate from device implantation decreases and simpler devices are developed with reliability further demonstrated, the threshold for percutaneous closure is likely to decline.
