But a researcher who has studied the issue for almost a decade tells WebMD that the jury is still out on the treatment.
In the new study, patients with PFOs who had a minimally invasive catheter-based procedure to close the small hole in their heart had significantly fewer disabling migraines than patients with PFOs who did not have the procedure.
Migraines and PFO Closure
As many as one in four people have a PFO abnormality, but most never know it.
While not everyone with PFOs has migraines and not everyone with migraines has PFOs, studies show that migraine sufferers are far more likely to have the heart abnormality than people without migraines.
PFO researcher Peter Wilmshurst, MB, of the UK's Royal Shrewsbury Hospital, tells WebMD that about half of patients with a specific type of migraine known as migraine with aura have large PFOs or similar openings in their hearts compared to about 5% of the population at large.
Wilmshurst did not participate in the new study, but he was involved in an earlier study that examined PFO closure as a treatment for migraines. Published last year, that study, known as the MIST trial, found no benefit for the treatment.
The new study included 82 migraine patients who had large PFOs and no history of strokes. All the patients also had a type of brain lesion that is commonly seen in brain scans of patients with migraines.
Fifty-three of the patients had the PFO closure procedure and 29 did not.
At six months follow-up, the PFO closure patients showed significant improvements in both the frequency and severity of their migraine headaches.
In all, 53% of patients in the PFO closure group reported a disappearance of disabling headaches, compared to 7% of the patients who did not have the closure procedure; 87% in the closure group reported a more than 50% reduction in total headaches, compared to 21% of the patients in the comparison group.
The study appears in the Feb. 24 issue of the Journal of the American College of Cardiology.
"Only patients in the closure group reported a significant reduction of migraine severity, which is crucial for quality of life," study researcher Carlo Vigna, MD, and colleagues write. "In contrast, the number of disabling attacks did not change or increased in 41% of controls."
Why Findings May Vary
In an accompanying editorial, Wilmshurst suggests that the placebo effect may explain why the findings in the latest trial are so different from those in MIST trial.
The 147 MIST participants had no idea which treatment they were getting, but the 82 patients in the latest study chose the treatment they received.
"It is possible that in patients with migraine the placebo effect from an operative intervention might be much greater than the magnitude of placebo effects with drug treatments," he writes.
But Wilmshurst tells WebMD that this doesn't explain why early studies showed PFO closure to be an effective treatment for migraines. That's because patients in these early trials had the procedure for other reasons and had no expectations that their headaches would improve.
Several devices used for PFO closure are being marketed in the U.S., and Wilmshurst says PFO closure is commonly performed in patients with migraines even though it is considered experimental and the devices have not been approved for the treatment of migraines by the FDA.
"Some people would ask if we should really be using this treatment, since we can't say for sure that it works." he says. "I don't really know the answer to that question."