[Migraine and patent foramen ovale].

Observational studies indicate an increased prevalence of patent foramen ovale (PFO) in migraineurs with aura and an increased prevalence of migraine and migraine with aura in patients with PFO but a recent stratified meta-analysis does not support pairwise association between PFO and migraine. There are conflicting data regarding causal relationship between these two conditions. According to recent studies, microembolization might provoke a decrease in cerebral oxygen saturation, thus triggering cortical spreading depression and, thereafter, migraine with aura attack. Release of vasoactive substances by activated platelets or atrial natriuretic factor are other pathophysiological explanations. Retrospective analyses of PFO closure suggest clinically significant improvements in migraine patterns. The MIST study is the only prospective study available with a good design but this study gave a negative response about cure of migraine with aura and revealed a high morbidity for such a benign condition. Although PFO closure sometimes appears to affect migraine patterns favorably, the very low grade of available evidence to support this association precludes definitive conclusions. To date, PFO closure in migraineurs with aura is not recommended in daily practice.