Closure of a patent foramen ovale is associated with a decrease in prevalence of migraine: a prospective observational study.

Background: A causal relationship between migraine and a right-to-left shunt, due to a patent foramen ovale (PFO), has been suggested. In mainly retrospective studies, percutaneous closure of a PFO has been associated with a decrease in the prevalence of migraine.
Objective: In this prospective observational study we evaluated whether percutaneous closure of a PFO is associated with a decrease in the prevalence of migraine.
Methods: Between November 2003 and August 2005, we included 92 patients (age >16 years) who underwent a percutaneous closure of a symptomatic PFO, which was considered to be related to a paradoxical embolism.They received a headache questionnaire before and six months after closure.Two neurologists diagnosed migraine, according to the International Headache Criteria.
Results: Eighty-nine of 92 patients (97%, mean age 51.6 +/- 12.3 years, 63 men) completed the questionnaire immediately before PFO closure.The overall prevalence of migraine was 27.0%, for migraine without aura (MA-) 15.7%, and for migraine with aura (MA+) 11.2%. After more than six months of follow-up 84 of 89 patients (94%, mean age 52.1 +/- 12.0 years, 60 men) returned the questionnaire. The overall prevalence of migraine in this group decreased from 28.6% to 10.7% (P = 0.001), for MA-from 16.7% to 8.3% (P = 0.07), and for MA+ from 11.9% to 2.4% (P = 0.02).
Conclusions: Percutaneous PFO closure is related to a decrease in the prevalence of migraine in this prospective observational study. However, randomized placebo controlled trials have to confirm these findings.