Cerebrovascular events are associated with high rates of morbidity and mortality and are considered the global second leading cause of death.1 The majority of strokes are ischemic, although the etiology remains unknown in a considerable number of patients,2 commonly referred to as “non-defined” or “cryptogenic.”3 Data from epidemiologic studies point towards a relevant association between the prevalence of a patent foramen ovale (PFO) and the occurrence of cryptogenic stroke or embolism.4 Thus, paradoxical embolism via PFO has been suggested as plausible mechanism and etiology of cryptogenic cerebrovascular or other embolic events in a considerable number of patients.5,6
Percutaneous PFO closure has been proposed as effective treatment for the secondary prevention of recurrent cerebrovascular or peripheral embolism, and several devices have been introduced into clinical practice. Observational studies investigating percutaneous PFO closure for patients with presumed paradoxical embolism suggested a substantial benefit in the secondary prevention of recurrent neurologic and vascular events over medical therapy,7,8 and even a mortality benefit during long-term follow-up when comparing patients after device closure with patients before or without PFO closure.7