Anatomy of a Stroke
Stroke is the fourth leading cause of death; it’s most common among seniors but it can strike at younger ages, even in childhood. And yet for many…stroke remains a mystery.
KLEINDORFER: It's a huge killer of people across the country and the public doesn't even know what part of the body we're talking about.
Dr. Dawn Kleindorfer should know. She’s co-director of the research team that provides the data that's used to tally national stroke statistics by the Centers for Disease Control and the National Institutes of Health. She’s also a neurologist at the University of Cincinnati College of Medicine.
KLEINDORFER: People understand heart attack, and heart attack is an emergency, but you say stroke and they say, that's when you get really hot isn't it? It's like, no that's heat stroke, that's different, we're talking about basically a heart attack of the brain.
“A heart attack of the brain”… that’s one way to describe what’s going on during a stroke. Another analogy comes from Dr. Anthony Furlan, also a neurologist who specializes in stroke care.
FURLAN: I often joke, "I'm a plumber"-I've become a plumber.
Furlan who’s at University Hospitals in Cleveland says stroke is very much a plumbing problem because the majority of strokes are caused by a blockage of a blood vessel that feeds the brain. To understand this, visualize the underbelly of your bathroom sink or tub.
FURLAN: If your pipes are plugged, you have to find where that hairball is in your shower drain or your pipes. And it's usually in the trap-in the U part of the drain-so the same thing with the blood vessel. The straight part usually the clot doesn't stop there but when it hits that U turn, or where the blood vessel branches, that's where it gets stuck.
That "hairball," plugging up the blood's path to the brain, is often caused by fatty plaque buildup, the same culprit in heart attack. That plaque can rupture the lining of a blood vessel and cause a clot, or pieces of it can break off and jam up an artery. Other conditions--like stagnant or pooling blood--can also cause clots to form. And once those clots block blood flow, they cause a cascade of problems.
FURLAN: So the brain does not tolerate a cut-off of its nutrients, of its blood supply, for very long. That's why we have to act fast when we're treating stroke.
Without oxygen that blood flow brings, brain cells start dying at a rapid clip--32,000 a second. Doctors sometimes refer to a golden "3 hour window" after stroke onset, when treatment can have the most effect.
The go-to drug for busting a clot right at stroke onset is called TPA, which was FDA approved in 1996--a date that many in the field regard as a groundbreaking moment in stroke care.
Along with TPA, new devices allow doctors more time to unplug the clot. They can thread a catheter up through the blood vessels and actually suck out the clot. Back to pipes' expert, Anthony Furlan at UH:
FURLAN: Using the plumbing analogy, if you use that snake in your drain to pull the plug out, so these devices pretty much work like drain snakes, if you will, and pull that clot right out of the artery.
The drug TPA then, would be like Draino.
So, with most strokes, the problem is a blockage that can starve the brain of oxygen.
How can we tell if this is happening to us or someone around us?
FURLAN: The hallmark of stroke is sudden. I mean you're fine, just like we're sitting here talking and boom, I'm blind.
Loss of vision is one symptom of a stroke. So is loss of speech or abrupt paralysis of a limb or numbness down one side of the body…these are all indications of a stroke. There's one symptom conspicuously absent from this list though: pain.
FURLAN: Stroke is a painless thing. In fact you can touch the surface of the brain during surgery and there's no pain. The brain is a painless organ, interestingly enough. So pain almost never is a symptom of stroke.
The only exception, says Furlan, is the pain of sudden intense headache, which can be a symptom of a rarer type of hemorrhagic stroke, which is a bleed in the brain.
If you experience even just a few moments of these symptoms--sudden intense headache, paralysis, speech loss or the others--and then they pass, you still need to seek care, experts say, because these are warning events--called Transient Ischemic Attacks, or TIAs, and they indicate a larger problem on the horizon. After a TIA, chances are high that you're in for a stroke.
The best medicine is, of course, prevention. Dr. Furlan:
FURLAN: I mean you can cut your risk of having a stroke in half--in half--by just treating your blood pressure and your risk factors.
Risk rises appreciably with high blood pressure and cholesterol, diabetes, lack of exercise, obesity, and smoking.
The odds of surviving a stroke have increased dramatically in the last 20 years and strides have been made in recuperation when treatment begins quickly. For many though, the damage is permanent. Again, Dr. Furlan.
FURLAN: It's a very difficult thing to say treat a 50 year old person who is working in the morning and now is totally paralyzed, can't talk, and can't see, and is going to be that way for the rest of his or her life. And that's what a stroke does.