An Overview of Migrainous Infarction

"Migrainous infarction" is a term that was originally coined by the International Headache Society to describe strokes that start during a migraine attack with aura symptoms that last for an hour or more.

Considered a complication of migraine, these strokes are very rare, accounting for approximately 0.5% to 1.5% of all ischemic strokes—a type of stroke that occurs when you lose blood supply to your brain.

This article explores the symptoms, causes, diagnosis, treatment, and prevention of migrainous infarction or stroke.

Symptoms of Migrainous Infarction

Not every stroke that occurs while you have a migraine can be called a migrainous infarction. According to the International Headache Society's definition, the following characteristics must be present:

• The migraine attack must be similar to previous migraine attacks.
• There must have been an aura, typically a visual one.
• At least one of the aura symptoms must persist for an hour or more.
• A stroke must be seen on a computed tomography (CT) or magnetic resonance imaging (MRI) scan.
• All other possible causes of stroke must have been ruled out.

Along with typical migraine symptoms, migrainous infarction symptoms generally start suddenly and may include:

• Visual disturbances such as flashes of light, blind spots, blurry vision, or other visual changes
• Weakness or numbness, especially on one side of the body
• Aphasia (loss of the ability to talk)
• Confusion
• Balance and coordination issues that cause difficulty walking

What Causes a Migrainous Infarction?

Migrainous infarctions occur more frequently in females than in males, especially before the age of 50. It's unknown exactly what causes these strokes or why there's an increased risk of stroke in people who have migraines with aura, but there are several theories, including:

• Genetics: Certain genetic disorders are associated with both stroke and migraine.
• Common comorbidities: The presence of other medical conditions can be the same in both stroke and migraine. For instance, both are associated with patent foramen ovale (a congenital heart defect), endothelial dysfunction, Sneddon syndrome, antiphospholipid antibody syndrome, and lupus.

How Is a Migrainous Infarction Diagnosed?

If you have aura symptoms that last longer than an hour, you should see your healthcare provider so that they can check for a loss of blood supply to your brain. You'll have the same diagnostic workup as anyone with ischemic stroke, which includes:

•  A review of your symptoms and medical history, a physical exam, and blood tests
• Imaging tests, such as computed tomography (CT) scan, magnetic resonance imaging (MRI), digital subtraction angiography (DSA), and/or positron emission tomography (PET)
• Possibly an electrocardiogram (EKG)

Rarely, it's also possible to have a migraine aura that lasts for up to a week or longer without a stroke. This condition is referred to as persistent migraine aura without infarction and should be evaluated by a medical professional.

Your healthcare provider will use imaging tests to see if the stroke is affecting the same area as your migraine. If so, your practitioner will likely diagnose a migrainous infarction.

Treatment for Migrainous Infarction

For most people, treatment is the same as it is for any ischemic stroke and may include:

• Medications to treat stroke: If you get help within three hours of the time you first started having symptoms, you'll be put on a medication that helps dissolve the blood clot(s). You may also be given medication to help decrease the swelling in your brain.
• Supplemental treatments: You may need intravenous (IV) fluids to keep you hydrated and/or oxygen to help you breathe.
• Preventative medications: Your healthcare provider will likely advise you to avoid medications that can induce a migraine while also giving you medication that will prevent one.

Other potential treatments depend on the severity of your stroke and what underlying condition(s) may have caused it. In general, your practitioner will work to decrease your risk of complications from stroke and prevent future strokes, while also treating your migraines and any other medical condition that may have been a factor.

How to Prevent a Migrainous Infarction

It's important to take preventative measures and make any necessary lifestyle changes that can help lower your chance of having migrainous infarction. Factors that increase your risk when you have migraine with aura include:

• Smoking
• Obesity
• Sedentary lifestyle
• Oral contraceptives (birth control pills)
• Untreated diabetes, high blood pressure, or dyslipidemia (abnormal cholesterol levels)

Summary

A migrainous infarction is characterized as a stroke that starts during a migraine attack with aura symptoms that last for an hour or more. It's unknown what causes migrainous strokes, but genetics and comorbidities are thought to be involved.

The first rule of thumb is to see your healthcare provider or go to the emergency room if you have a migraine with aura for over an hour. Thankfully, these strokes are usually mild and generally result in a complete recovery.