In patients with a cryptogenic stroke the prevalence of a patent foramen ovale (PFO) is increased to approximately 50% compared with a 25%-30% prevalence rate in the general population. This leads to a plausible assumption that a considerable number of strokes could potentially be attributed to a PFO, most likely due to paradoxical embolism. It is estimated that the risk for an embolic stroke due to the presence of a PFO may be 9-fold higher than that related to hypertension, diabetes or hypercholesterolemia. Furthermore, in the presence of an interatrial septal aneurysm (IASA), this risk may even be 30-fold higher. The management of patients with a cryptogenic stroke and a PFO is currently based on antithrombotic or anti-platelet therapy, however the recurrence rate remains high (4-25%), and this has led to the recommendation of percutaneous PFO closure, which is now effected via a simple and relatively safe technique, which appears to reduce recurrences to 0-5%. However, the studies which provide such favorable data are only retrospective, which means that we are in dire need of prospective randomized studies that compare the two therapeutic approaches, before the interventional method is more widely adopted. In addition to cryptogenic stroke, the presence of a PFO has been also associated, among other conditions, with bouts of migraine and its percutaneous closure has been shown, albeit via retrospective and observational data, to eliminate or significantly improve this common condition. The only prospective randomized trial available (MIST trial) failed to show conclusively the superiority of PFO closure to medical treatment with regards to elimination of migraine.Another large group of patients undergoing percutaneous closure of an interatrial communication are those with a secundum atrial septal defect (ASD). The majority of these patients, at least those having defects as large as 35-38 mm and an adequate rim to support a closure device, can now be successfully submitted to the percutaneous technique and thus avoid surgery. Certainly, these patients could also suffer from cryptogenic strokes and migraine, however, most of them usually require intervention because of hemodynamic reasons.The technique of percutaneous closure of a PFO or an ASD performed by adult interventional cardiologists is indeed a relatively simple and swift procedure of right heart catheterization, carried out from the groin area via the femoral vein with use of local anesthesia. Complications related to the procedure are limited to ≤1-3.4%. Due to this paradigm of technological progress, a rapid growth of procedures of percutaneous closure of ASD and PFO has been noted over the last decade, particularly over the recent 4-5 years. Nevertheless, one has to resist in widely and hastily adopting such methods before further strong evidence becomes available via randomized prospective studies
