title: Patent foramen ovale and migraine attacks: a systematic review.
abstract: BACKGROUND
  Migraine headache and the presence of a patent foramen ovale have been associated with each other, although the precise pathophysiological mechanism(s) are uncertain. The purpose of this systematic review was to identify the extent of patent foramen ovale prevalence in migraineurs and to determine whether closure of a patent foramen ovale would improve migraine headache.
  
  
  METHODS
  An electronic literature search was performed to select studies between January 1980 and February 2013 that were relevant to the prevalence of patent foramen ovale and migraine, and the effects of intervention(s) on migraine attacks. Of the initial 368 articles presented by the initial search, 20 satisfied the inclusion criteria assessing patent foramen ovale prevalence in migraineurs and 21 presented data on patent foramen ovale closure.
  
  
  RESULTS
  In case series and cohort studies, patent foramen ovale prevalence in migraineurs ranged from 14.6% to 66.5%. Case-control studies reported a prevalence ranging from 16.0% to 25.7% in controls, compared with 26.8% to 96.0% for migraine with aura. The extent of improvement or resolution of migraine headache attack symptoms was variable. In case series, intervention ameliorated migraine headache attack in 13.6% to 92.3% of cases. One single randomized trial did not show any benefit from patent foramen ovale closure. The data overall do not exclude the possibility of a placebo effect for resolving migraine following patent foramen ovale closure.
  
  
  CONCLUSIONS
  This systematic review demonstrates firstly that migraine headache attack is associated with a higher prevalence of patent foramen ovale than among the general population. Observational data suggest that some improvement of migraine would be observed if the patent foramen ovale were to be closed. A proper assessment of any interventions for patent foramen ovale closure would require further large randomized trials to be conducted given uncertainties from existing trial data.
authors.affiliation: Department of Cardiovascular Medicine, University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, United Kingdom.
authors.forename: Philomena Z Y
authors.initials: PZ
authors.lastname: Lip
authors.affiliation: Department of Cardiovascular Medicine, University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, United Kingdom. Electronic address: g.y.h.lip@bham.ac.uk.
authors.forename: Gregory Y H
authors.initials: GY
authors.lastname: Lip
mesh_terms: D016022:Case-Control Studies; D054092:Foramen Ovale, Patent / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008881:Migraine Disorders / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control; D064887:Observational Studies as Topic; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D016896:Treatment Outcome
keywords: Migraine; Migraine headache; Patent foramen ovale