The mechanism by which patent foramen ovale (PFOs) are associated with ischemic stroke is believed to be paradoxical embolism. It has been observed that people with migraine with aura have a larger than expected concomitant prevalence of PFO compared to people without migraine. Transient global amnesia is considered to have a similar pathophysiology to migraine, and an association with PFO has also been observed. The mechanisms by which obstructive sleep apnea (OSA) increases the risk of ischemic stroke are multiple and all contribute to the ischemic event. As the risk seems associated with the multiple physiological abnormalities that accompany OSA and facilitated by a PFO, stroke prevention could potentially be achieved by improving OSA and reducing the right-to-left shunt treatment, antithrombotic therapy, PFO closure. Antithrombotic therapy should be given as well, in light of the greater overall cardiovascular risk.