Patent Foramen Ovale and Migraine Headaches

Patent foramen ovale a little hole in the heart.  Everyone is born with a tiny flap-like opening between the heart's two upper chambers. Usually, it grows shut during infancy. But in at least 20 percent of the population, the opening doesn't heal over.

That is the defect called "patent foramen ovale" or PFO.

So how does it link to migraine suffers and those that suffers strokes?  Doctors aren't certain, but the Food and Drug Administration has taken an unusual step to push manufacturers to settle the issue, stopping promotion of the expensive implants.

"What's really incumbent upon us now is proving these relationships and proving that closing the hole is beneficial," says Dr. Robert Sommer of Columbia University Medical Center, who implants the devices and is helping to study them.

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The Associated Press reports that when blood returns to the heart, it's supposed to go to the lungs to pick up more oxygen and be filtered clean. A PFO can allow some blood to seep back into circulation without that filtering step. The theory: That could allow small blood clots or other substances into the bloodstream, traveling straight to the brain.

Now the migraine connection.  In the late 1990s, cardiologists started aggressively sealing PFOs in stroke survivors, in hopes of lowering their risk for further strokes. They threaded tiny implants into the heart through a hole in the groin, pulling them against the PFO's flap to seal it shut.

The same report details that some implant recipients started reporting an odd side effect: Their migraine headaches went away. Subsequent research suggested at least 40 per cent of people who suffer a severe type of migraine -- the kind that comes with an "aura" or visual disturbance -- have fairly large PFOs.

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So now the debate and further studies are needed to better understand the association. Dr. Joseph Carrozza of Boston's Beth Israel Deaconness Hospital debated about whether to even close the holes at an international cardiology meeting last week.

"Association is not causation," Carrozza said, noting that the vast majority of people with PFOs will never report symptoms, and that PFO closure occasionally causes such serious side effects as blood clots and irregular heartbeats.

"I would argue passionately . . . we need the data."

--Compiled from wire reports