Migraine headache patients reported the painful attacks eased or even vanished after they underwent procedures to close abnormalities that allow blood to flow between the atria of their hearts, according to the results of <<>> in the current issue of the Journal of the transient ischemic attack.
“What we observed is that after closing the opening between heart atria, there was a dramatic reduction in the incidence of migraine headaches in those patients who had complained of headaches prior to the inter-atrial closure procedure,” said Jonathan Tobis at the University of California in Los Angeles.
Dr. Tobis and his colleagues, including lead author Babak Azarbal, M.D., reviewed 89 cases in which a device was threaded through a catheter into an abnormal intra-atrial opening. Almost half the patients (37 of 89) reported suffering migraine headaches before the procedure. By contrast, only 12 percent of the general population reports suffering migraines. Three months after the procedure, three-quarters of the migraine sufferers (28 of 37) reported their migraines were gone or significantly improved.
In the migraines, Mark Reisman, M.D., and his colleagues in Seattle, Wash., reviewed 162 cases of patients who underwent a transcatheter procedure to close an intra-atrial opening because they had suffered a stroke or transient ischemic attack. A type of intra-atrial opening known as patent foramen ovale is associated with these attacks.
“The results were extraordinary. We’ve been able to see a significant number of patients who have had not just a reduction in the frequency of headaches but actually complete relief,” said Mark Reisman, M.D. at Swedish Medical Center in Seattle, Wash. “This study further supports a link between a common heart abnormality and migraine headache.”
Of the 162 patients studied, 57 (35 percent) reported suffering migraines before undergoing the procedure. A year after the procedure, the researchers contacted 50 of the migraine suffers. More than half (28 of 50) said their migraines were gone and another seven patients said the frequency of migraine attacks had dropped by more than 50 percent.
Although many migraine suffers are eager for any procedure that could offer them potential relief from the debilitating attack, both Dr. Reisman and Dr. Tobis stressed that randomized, controlled clinical trials are needed before recommending heart procedures as a possible migraine treatment. They also noted that there are migraine suffers who do not have heart abnormalities, and people with intra-atrial holes who do not suffer migraines; so the link seen in these studies, even if confirmed, does not explain all migraines.
The studies involved patients receiving treatment for patent foramen ovale or atrial septal defect. Patent foramen ovale (PFO) is a flap valve that allows blood to flow directly from the right atrium to the left atrium of the fetal heart when oxygen is supplied from the mother and the developing lungs are not yet in use. After birth, when a newborn begins breathing and blood flows through the lungs, blood pressure increases on the left side of the heart, which generally holds the PFO flap closed. Although the flap is usually permanently shut by the first birthday, one person in five still has an open PFO into adulthood. Atrial septal defect is an abnormal opening through the muscle wall (septum) that separates the left and right atria of the heart.
Dr. Reisman said his team decided to look into possible links between heart abnormalities and migraines after patients began spontaneously telling them that their headaches had disappeared after the catheter procedures.
“This is a huge leap in our understanding about the potential causes of migraine headaches. For centuries there have been explanations for migraine headaches that run the gamut from demons to vascular spasm. However, there has been no good scientific explanation for these headaches,” Dr. Tobis said.
These studies were not designed to uncover how a hole in the wall between heart chambers could cause migraines, but researchers have some suspicions. The blood normally circulates through the lungs on its way from the right atrium to the left atrium, but the atrial wall hole short-circuits that usual route. So the researchers said future studies should look for signs of impurities or tiny clots passing through the intra-atrial hole that may be filtered or metabolized by the lungs in a person with normal circulation.
Because of the dramatic nature of the changes reported by patients in these observational studies, Dr. Reisman said a more definitive clinical trial could be done with in a couple of years.