Migraine sufferers are more likely than others to retain the opening between the left and right atria which usually closes in childhood.
Researchers looked at the effect of closing this opening, the patent foramen ovale (PFO), in 53 patients with migraine and subclinical brain lesions.
Patients' six-month outcomes were compared with those of 29 controls. Previous studies of such surgery in migraine have not tended to be controlled prospective studies of this type.
The researchers found that PFO closure reduced the number of migraine attacks by 82 per cent and disabling attacks by 90 per cent.