Virtually everyone has experienced it at one time or another: the headache, that persistent, aching pain that affects portions of the head and neck, usually as a result of stress or tension. Less common but much more severe is the migraine, a particular type of headache where the pain is so intense, it can be debilitating. Migraines affect nearly 40 million Americans over age 12, and are three times as common in women as in men.
According to Dr. Robert Sommer, a specialist in Congenital Heart Defects at New York-Presbyterian, “A migraine is a disorder characterized by severe headache and generally associated with nausea and/or light and sound sensitivity. About a quarter of sufferers experience aura prior to migraine onset —manifesting in such symptoms as flashing lights, shimmering spots, zigzag lines that float across a person’s field of vision, or partial visual loss. Although neurological in nature, new research is pointing to a possible connection between migraine with aura and a certain heart condition.”
A cardiac solution to a neurological problem?
Migraine headaches remain poorly understood, and there are likely a number of underlying causes that result in their symptoms. Recent research studies have identified a possible link between migraine with aura and a congenital heart defect known as patent foramen ovale (PFO).
“The foramen ovale is a flap in the atrial septum, the wall located between the upper chambers of the heart, the left and right atria. While the flap is a critical part of the fetal circulation, and is present in all babies as the heart forms, it’s supposed to close on its own after birth. But in about 25% of the population, the hole remains open,” Dr. Sommer explains.
In the vast majority of cases, a PFO causes no health problems, but complications can arise. With a hole in the septum, non-oxygenated blood from the right side of the heart can enter the left side and mix with the oxygenated blood leading to symptoms of shortness of breath. The hole may allow for tiny clots, normally present on the right side of the heart, to cross over to the left side and, from there, travel to the brain, causing strokes.
“What links PFO to migraines is unknown, but research suggests that it is related to the platelets, the tiny blood cells involved in forming blood clots. Tiny clots, too small to cause stroke, may reach the brain triggering the migraines directly, or chemicals normally released by the platelets on the right side of the heart may cross over and be responsible,” says Dr. Sommer. “As many as 40 – 50 percent of individuals who experience migraines with aura also have a PFO — that’s twice the rate of patients without migraine, or with migraine without aura.”
New on the horizon
Since 2000, doctors who have been performing PFO closures with an umbrella device inserted with a small tube through a vein in the leg, have noticed that a large number of migraine sufferers have had a dramatic reduction in their migraine frequency. However, this effect is far from universal, and to date, there have been no reliable methods for choosing the patients who will respond to the closure procedure. But Dr. Sommer and his partner, Nurse Practitioner Barbara Robbins, have just completed two pilot studies in which a certain class of blood thinner medications (platelet inhibiting drugs) produce dramatic migraine symptom reduction in some patients.
Currently, Dr. Sommer is working with national leaders in the migraine field, and with other PFO experts, in developing a National Migraine PFO trial, which he hopes will be ready to begin enrolling patients this summer.
A matter of education
Currently, there are a variety of medications and therapies to treat migraines, but their efficacy is limited; they do not work for all patients or they may come with side effects. Says Dr. Sommer, “Our goal with our research is to get the neurologists to start thinking about the PFO as a possible cause — and to actually look for it as part of their routine evaluation. But the truth is, there really are no signs of the heart defect in most patients, and in the migraine patients, the migraines themselves are the sign. Without looking for the PFO, there is no way for the neurologist or the patient to know that they should see a cardiologist. So we are working to educate everyone.”
To learn more about cardiac services at NewYork-Presbyterian, visit nyp.org/heart.