Patent foramen ovale, systemic embolization, and closure.

Patent foramen ovale has become the subject of increasing interest in modern cardiovascular disease. This has been the result of several factors including, among others, description of paradoxical embolism, documentation of patent foramen ovale with right to left shunt, the rather ubiquitous use of echocardiography, the issue of stroke prevention, and more recently, the relationship between patent foramen ovale and migraine.