Patent foramen ovale (PFO) a congenital cardiac anomaly, with the prevalence being approximately 25 % in individuals has been found to be more common in patients with cryptogenic stroke and is considered the most common identified cause of stroke and stroke recurrence in patients younger than 50 years. Paradoxical embolism via right-to-left shunt is the presumed mechanism. Other factors especially atrial septal aneurysm may confer a higher risk of recurrent stroke. However, recent data have called into question the relationship between PFO and cryptogenic stroke as well as the closure of PFO as the best prevention modality in the population with recurrent stroke due to paradoxical embolism through PFO. Up to the present time there have not been any evidence based data in this field available. The answer for the treatment superiority will be given by ongoing randomized trials.