Further information: Congenital Heart Disease in the Adult: Interventional Therapy (see p311) from Cardiovascular Medicine, 3rd Edn*

One of the most controversial issues in cardiology in recent years has been to define the indications for closure of a patent foramen ovale (PFO). The newest indication for closure of the PFO has been to control migraine headaches. Not uncommon, PFOs have been found to occur in 10–25% of the population in the USA, and as much as 6% of the male population and 15–18% of the female population suffer from migraine headaches. Observational studies have suggested a pathophysiologic relationship in the prevalence of migraine headaches in patients who also have PFOs, and that closure of the PFO alleviated symptoms. In fact, the early studies came from a reported beneficial effect in the relief of migraine symptoms in patients who were undergoing closure for other indications.

The currently reported study [1] was the first large, prospective case-control study designed to test the association by using quantitative measures of migraine severity and core laboratory assessment of PFO with transthoracic echocardiography (TTE) and transcranial Doppler (TCD). Between August 2004 and December 2005, 360 subjects, 195 case subjects and 165 control subjects, were enrolled. Final matching yielded 144 subjects in each category for analysis. Odds ratios were calculated with conditional logistic regression in the matched cohort (n=288).

In the matched analysis, the prevalence of PFO was similar in case and control subjects (26.4% vs. 25.7%; odds ratio (OR) 1.04, 95% confidence interval (CI) 0.62–1.74, P=0.90). There was no difference in PFO prevalence in those with migraine with aura and those without (26.8% vs. 26.1%; OR 1.03, 95% CI 0.48–2.21, P=0.93). Therefore, no association between migraine headaches and the presence of PFO was found, and the investigators conclude that the focus should be on other mechanisms in the search to find the cause of migraine headaches.

In an editorial accompanying this article [2], the authors conclude that sufficient evidence does not exist for closure of a PFO for migraine to be considered standard medical practice and that further investigation into the mechanisms of migraine headaches is essential.

[1] Garg P, Servoss SJ, Wu JC, et al. Lack of association between migraine headache and patent foramen ovale. Circulation 2010;121:1406-12

[2] Gersony WM, Gersony DR. Migraine headache and the patent foramen ovale. Circulation 2010;121:1377-78