Migraines

Barbara Rizzardi, MD, Internal Medicine with Page Hospital’s Visiting Specialist Program

Question: I am concerned I may have a migraine. Can you tell me more about them?

Answer: Chronic migraine headache is one of the leading causes of visits to primary care physicians, affecting 20 percent of women and 10 percent of men.

In addition to a headache, migraine sufferers may experience neurologic symptoms such as visual scotomata (zig-zaggy waves or lines in the vision), transient visual loss, dizziness, vertigo, “brain fog” or confusion, memory and concentration difficulties as well as a variety of other deficits. 

Some patients may get all the neurologic symptoms listed above but no headache.  This is an “amigrainous migraine”.  In spite of the disabling symptoms and discomfort of a migraine, migraines have traditionally been considered benign and not expected to lead to permanent or significant long-term problems.  They may be precipitated by foods such as chocolate or MSG in Chinese foods, bright lights, stress, alcohol, sleep deprivation, or hormonal changes.   They have been treated with variable success with triptan medications such as sumatriptan, beta-blockers, antidepressants, and anti-seizure medication.

It has been known for many years that patients with migraines may have a higher risk of stroke than age-matched other patients.  It was originally thought that a migraine somehow caused spasm of the arteries in the brain and this might lead to clotting or obstruction to blood flow to the brain. 

It is now known that up to 60 percent of migraine patients who experience neurologic symptoms may actually have a “hole in the heart” which can cause blood clots to pass through the right side of the heart, bypassing the lungs where tiny clots are screened out, to the left side of the heart where the clots can be pumped to the brain.  These clots are called emboli and not only obstruct flow but release serotonin from the platelets in the clot which may initiate the typical migraine symptoms. The “hole in the heart” may be due to a patent foramen ovale (PFO) or atrial septal defect (ASD).   All infants are born with a PFO which closes in the majority of us at birth or within days to weeks after. A PFO is normal in a baby inside the mother’s womb as the baby is floating in amniotic fluid  with no need for “breathing”  and therefore the PFO shunts blood from the right heart, skipping the lungs, and pumps it directly to the left side of the heart and out to the body.   After birth, this shunting stops as the PFO usually closes spontaneously when the baby starts breathing air.

In up to 20 percent of all adults, the PFO fails to close.  With a persistent open PFO, clots may pass through the septum of the heart and result in migraine and stroke.  There is a 1-3 percent risk of stroke each year with an unclosed PFO or ASD.  These strokes may be tiny and go unnoticed or be devastating with permanent brain injury depending on the number of emboli and where they lodge in the brain.  The risk increases in scuba diving, flying, weight lifters, or in other activities which cause straining as straining opens the hole and increase the shunt.  

I now screen all migraine patients with neurologic symptoms for a patent foramen ovale or atrial septal defect.  The most efficient way to do this is with a bubble transcranial Doppler study, done as an outpatient in less than one hour.  An IV is inserted in a vein in the patient’s arm and agitated saline (which causes bubbles) is injected.   An ultrasound device is placed on the head which detects the saline bubbles.  If there is no PFO, no bubbles are detected in the brain.  If there is a PFO or ASD, a shower of bubbles may be detected.  The more bubbles, the greater the shunt, and the higher the risk of stroke.  So, if you experience migraines, it may not be “all in your head”, but perhaps “all in your heart”.