For a little while now, it’s been postulated that our old friend, the PFO — patent foramen ovale, or “hole in the heart” linking the left and right atria — might be involved in headaches. Of course PFO’s have long been linked to stroke, especially strokes in younger patients with fewer risk factors. But cardiologists are hearing stories about a connection to migraines, as well:
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.
Then some implant recipients started reporting an odd side effect: Their migraine headaches went away. Subsequent research suggested at least 40 percent of people who suffer a severe type of migraine _ the kind that comes with an “aura” or visual disturbance _ have fairly large PFOs.
None of that research proves a PFO actually causes the ailments, cautioned Dr. Joseph Carrozza of Boston’s Beth Israel Deaconness Hospital, in a debate about whether to 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.”
PFO’s are typically closed in percutaneous catheter procedures, where a mesh is introduced over the flap between atria. Earlier this year we cited a Frost & Sullivan award winner, Cierra, a company that’s developed a new closure system called PFX.
But before any migraine sufferers rush out to get their hearts checked, realize that the majority of migraine patients don’t have PFO’s — and like the doctor said, correlation is not causation. We’ll know if the headaches are caused by PFO’s hopefully in a few years.
More from Dr. Robert Sommers’ Migraine / PFO trial, ESCAPE