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For Dummies is a registered trademark of Wiley Publishing, Inc. in the United States and other countries. Used here by license.Let me hit you with the bad news first: Stroke kills, stroke destroys, stroke debilitates. Stroke is the third most common cause of death in the United States, and the number-one cause of serious disability. One year after the most common kind of stroke, approximately 30 percent of those afflicted will have died, and another 30 percent will have a moderate to severe disability. Now for some good news: Of those who experience the most common type of stroke, approximately 40 percent are left with only a mild or no disability one year later. And each year more people survive and recover from stroke as medical research continues to advance effective treatment. Today, recovery with improvement is the rule rather than the exception. Stroke is sometimes called a brain attack. I wish this label would catch on, because I think that people might then understand that stroke is an emergency — like a heart attack — and call 911 right away! A heart attack threatens your heart; a stroke threatens your brain. In truth, most stroke is like a heart attack: It’s a problem with blood vessels, and time is really important. However, heart attack is a little easier to recognize. First of all, the pain tells you something is wrong — and it is usually near your heart. Most strokes are painless, and the symptoms, a paralyzed arm or leg for instance, are not obviously related to the brain. Clearly, the more you know about stroke — its symptoms, causes, risks, treatment, and prevention — the better your chances of living a full and productive life with or, better yet, without stroke. And the first lesson is to learn what stroke is and how and why stroke occurs. If you’ve already had a stroke, there are many opportunities to reduce the disability that stroke causes and prevent another stroke attack. A serious stroke will affect your entire family. You can fight back together.
Attacking Out of the BlueStroke is nothing if not fast. Each year, as many as 750,000 people in the United States suffer a sudden and unexpected attack of the brain. When part of the brain is deprived of oxygen — which is what is happening when stroke hits — it doesn’t take long for the catastrophe to make itself evident. A minute or less. Whether it’s a sudden inability to speak, the crash of a dish from a hand that can no longer grasp, or loss of consciousness, a brain attack strikes its victims quickly and powerfully and without warning. Or does it? Although your stroke may occur in a lightning flash, it has most likely been years in the making, with conditions such as high blood pressure, high cholesterol, obesity, and diabetes possibly serving as warning signs that the brain is in danger. Basically, as these conditions cause wear and tear on your blood vessels, your risks increase of suffering either a blockage or rupture of a brain artery. And — suddenly — you’re in stroke mode. So how does it happen? It starts with the brain.
Real-life examplesA 57-year-old man arrives early at work to prepare for an important presentation he has to make at 10 a.m. At about 9:15 he notices a headache. He thinks this is unusual, because he doesn’t have many headaches. He remembers that he did forget his blood pressure medication. He continues to work for a few minutes and then notices his right hand is not working and he can’t concentrate. He calls for his assistant who finds him looking very unusual. His mouth is twisted. He starts to talk but his speech is difficult to understand. She asks if he is okay. He says no. He starts to get up but his right arm gives way and he almost falls. His assistant calls 911. A 68-year-old woman is preparing breakfast for herself and her husband. He has made the coffee and is reading the newspaper. He hears her drop a plate and looks up to see her standing and looking at her left hand. He asks her what’s wrong. She says she doesn’t know. Her face — particularly the way she is holding her mouth — looks unusual. She keeps looking at her hand. “My hand is numb,” she says. He asks her to sit down. She seems confused as he leads her to a chair. He asks if it hurts. She says no. “I think you’re having a stroke,” he says. He dials 911. A 38-year-old lawyer is out jogging on a canal towpath. She starts to feel pain in her head that gets worse and worse. She stops, puts her hand to her head, and falls to the ground. A man walking ahead of her sees her fall. He runs to her but she is unconscious. He pulls out his cell phone and dials 911.
Going to the source: Stroke is in the brainBecause of a number of possible causes — which I explain in detail in this book — part of your brain may be deprived of blood. When that happens, it doesn’t take long for your brain to suffer. In a nutshell, the glucose and oxygen transported by one of the brain’s arteries are not reaching some part of the brain, which in less than a minute will begin to shut down. And you will show signs of stroke. The 50 professional groups forming the Brain Attack Coalition describe the signs of stroke as follows:
Sudden numbness or weakness of face, arm, or leg, especially on one side of the body
Sudden confusion, trouble speaking or understanding speech
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden severe headache with no known cause Most of the time, a stroke victim feels no pain as the stroke is occurring — so there is not much evidence to clue you in that the reason your hand looks funny and doesn’t move when you want is because there’s something wrong in your head. Most people who have a stroke don’t know what is happening to them. Most people who see someone who’s had a stroke don’t know what is happening. A stroke doesn’t hurt (except if a headache accompanies it), and its most obvious effects are far from the brain where the problem is located. This means a lot of people don’t recognize they are having a stroke and can’t use the opportunities they have to get into the hospital quickly and be treated.
Damage in your brain, symptoms someplace else
So, why is it that a blocked artery in your brain causes you to lose control of your legs and fall to the floor? Suppose a small blood clot forms in your heart and flows with the blood up into your brain and plugs an artery that feeds a part of your brain near the top of your head. Normally, that part of the brain sends nerve impulses down threadlike fibers through the base of your brain and along your spinal cord down to a point a couple of inches below your lowest rib. There those nerve fibers connect to other nerve fibers that extend down to muscles in your legs. But without blood flow, the affected part of the brain stops sending messages. Your leg muscles only work when they receive messages, so they stop working. But the other parts of your brain that are getting oxygen and glucose don’t understand that the whole team’s not on board and look at the leg in confusion, trying to comprehend why it’s not cooperating, not realizing that the problem is right upstairs. The brain is sensitive to the slightest touch of your skin, but completely insensitive to serious injury to itself. As remarkable as it may seem, the brain is very poor at recognizing when it has been injured. This makes it hard for you to figure out what is going on when you have a stroke.
Responding quickly: Time is brain
Your brain is completely unprepared when blood flow is cut off. The organ is so packed full of knowledge and memories that there is no room in the design for storing sugars and fats that could keep brain cells alive in hard times when blood stops flowing. Most other cells in the body can survive for up to an hour without blood flow. The brain cells stop working in a matter of seconds and start dying after five minutes. The brain counts on the heart to do its job. That’s why when you have a heart attack it is so important to get the heart restarted quickly. Within seconds after your heart stops, your brain stops working. Within minutes of the heart stopping, the brain is permanently injured and can’t recover even if the heart gets going again. In stroke, you have a little more time than in a heart attack. Because the heart keeps pumping, some blood can often get around the obstruction or broken portion of the blood vessels, or seep in from areas of the brain that are still getting blood. But get yourself to a hospital right away. Call 911. If you are going to get the best treatment, you need to get to a hospital within 60 minutes.
Recognizing Types of Stroke: Same Symptoms, Different Causes
Doctors can typically identify stroke when a patient comes in with symptoms — they’re even pretty good at knowing what part of your brain may be damaged by the stroke just by looking at you. With some scenarios, such as a bursting aneurysm, a doctor can guess what caused the stroke. With other cases, it is almost impossible to tell what caused the stroke, although there is little doubt that a stroke is in progress. Sometimes, with severe headache, for example, it’s hard to tell whether a stroke is happening at all because the symptoms are similar to those of a migraine headache. A stroke might cause dizziness that is difficult to distinguish from an inner-ear infection. Fortunately, testing instruments such as CT or MRI scans can indicate if there is a stroke and what its cause might be.
Red or white: Color-coding stroke types
A friend of mine, a cardiologist, once told me that neurologists make stroke too complicated with their jargon and classification. He said he just thinks of stroke like wine: There’s red wine and white wine — and red stroke and white stroke. What did he mean by this? Basically, some strokes are caused by broken blood vessels — which results in blood in the brain or brain area (thus, the red); other strokes are caused by the blockage of vessels to the brain, so no blood gets there (hence, white). I liked his use of the color-coding and have found that when I talk to patients and their families, this explanation helps them better understand the cause of the stroke and what is happening in the brain. So throughout this book, you’ll see that I classify the five major types of stroke into two general categories based on whether they are caused by bleeding (red) or blockage (white). Oh, don’t worry — I promise to give you the complex, hard-to-pronounce terminology, as well! Throughout the book, you will find the most commonly accepted medical terms for the types of stroke. If you’re ready now to track it down in a medical textbook, you’ll find out more about red stroke under the term hemorrhagic stroke or intracerebral hemorrhage. White stroke is covered under the term ischemic stroke, embolic stroke, or thrombotic stroke.
Understanding white stroke
As you age, your blood pressure, diet, and the ravages of time roughen the fragile lining of your blood vessels and heart. Your blood-vessel lining is like the coating on your best cookware — it keeps your blood from sticking and clotting. However, as you approach senior status, that Teflon-like protection starts breaking down, and your vessels develop spots where blood and other buildup stick to them.
Blood clots block blood to the brain
The most common sign of blood-vessel damage is atherosclerosis, also known as hardening of the arteries, the condition in which a rough, scarred area called a plaque forms because of high blood pressure and high fat content in your blood. The roughness makes it more likely that blood inside your arteries will form clots that can block arteries in the brain or break up into smaller pieces that are carried downstream to lodge in small brain arteries. Sometimes blood clots can break off and flow downstream to form a blockage somewhere else, called an embolism If the clot blocks blood to a part of your brain, you have a stroke. If the clot stays in place for even a short time, part of your brain dies, leaving a hole called a brain infarction. The affected area of brain turns from pink to white because there is no red blood flowing (another good reason to refer to this type of stroke as white).
Dissection: Blood vessel lining splits
White ischemic strokes are also caused by dissection. No, this doesn’t mean somebody is practicing brain surgery on you. Dissection refers to the splitting of the blood vessel lining, typically occurring at a place where the blood vessel bends back and forth, such as in your neck. It can also happen where atherosclerotic plaque has built up in a brain artery. At the bend point or at the rough surface of atherosclerosis, a little flap of the vessel lining peels off and catches the blood as it flows quickly past. The blood dives under the flap and keeps tearing it. Eventually the blood can pack the lining against the other side of the vessel and stop blood flow completely. When the blood stops flowing, a white stroke occurs.
Transient strokes: Just as serious
White ischemic strokes may last just a couple of minutes and then clear completely. If the blood clot breaks up right away, the stroke is transient — so fleeting that no permanent tissue death occurred. These transient strokes are officially called transient ischemic attacks. Try to say that ten times fast. Doctors abbreviate it as TIA. I don’t like the term TIA or what it stands for because it doesn’t tell you plainly that you had a stroke. A stroke is very serious even if it is transient, and you still need to consider it a medical emergency requiring a rapid response. After a TIA stroke, your next stroke may not be transient and you need to get busy to prevent it from happening. It could happen tomorrow. You can have more than one transient ischemic stroke. As the number of these small strokes add up, your brain can just slow down generally, and you can suffer from dementia, as each small stroke erodes away more of your brain. Small white ischemic stroke dementia is often called vascular dementia or vascular cognitive impairment. This is the death of the brain by a thousand cuts.
A stroke by any other name
Stroke means that part of your brain has suddenly stopped working because of a problem with its blood supply. It may help to think of strokes caused by blockage as white strokes; they’re most typically referred to as ischemic strokes by doctors. But here are some other names for this type of stroke: occlusive stroke cerebrovascular accident (CVA) acute ischemic stroke atherothrombotic stroke embolic stroke small vessel stroke lacunar stroke large vessel stroke cardioembolic stroke Ischemic stroke and CVA are probably the most common terms used. Doctors usually know what all these terms mean and use them each in different situations to mean virtually the same thing. “Little white stroke” and “big white stroke” could probably replace all these fine technical terms just as well, and everyone would know exactly what they meant. I refer to strokes caused by bleeding in or around the brain as red strokes. Names for these types of stroke are equally varied: subarachnoid hemorrhage (SAH) intracranial hemorrhage intracerebral hemorrhage (ICH) brain bleeding brain hemorrhage Atherosclerosis Atherosclerotic plaque Embolism Blood flow Blood flow Blood clot from heart or broken off from clot on artery wall upstream Blood clot forms in vessel.
Getting a handle on red stroke
Blood vessels can break and bleed into or around the brain, causing some of the most serious and deadly strokes. These type of strokes may result in similar symptoms to white stokes — although some are unique to red stroke — but in many cases, they should be treated differently.
Bleeding within the brain
A stroke caused by a blood vessel that breaks inside the substance of the brain is called intracerebral hemorrhage, brain hemorrhage, or brain bleeding. The brain goes from pink to red. Hence, the term red stroke. The vessels that bleed are often damaged extensively by high blood pressure or diabetes (Figure 1-3). The blood vessels have thick, fibrous, but weak walls. They form little blebs — bubble-like growths — from time to time. These brain vessels are very prone to break, especially when blood pressure is high.
Bleeding around the brain
Sometimes red — or hemorrhagic — strokes are caused by bleeding just outside the brain, but still inside the skull. This type of red stroke is known as subarachnoid hemorrhage. The most common cause in this case is a little peanut or marble-sized bubble or pouch that forms at a Y-junction in a brain-bound artery. This bubble is called an aneurysm. It has tough, thin, rubbery walls and may actually be present for years before it starts causing trouble. Some never do cause trouble. But aneurysms may get larger as time passes and, as they do, doctors believe they are more likely to burst. The result can be devastating as high-pressure blood from larger brain arteries floods into the space around the brain. If you aren’t killed immediately, you have to survive weeks of recovery as your body tries to clean up the resulting mess. Further injury to your brain and rebleeding are likely, unless you get immediate medical attention. This type of red subarachnoid hemorrhage stroke is usually accompanied by severe headache. Many people also fall down unconscious when the stroke first hits. The pain and loss of consciousness are both strong warnings that something serious is happening.
When red and white stroke occur together
White ischemic strokes can turn red if a blood vessel is injured and breaks in the area where lack of blood flow caused a brain infarction. The bleeding can become a major intracranial hemorrhage or it may just be a small leak that doesn’t do much more damage than has already been done by the ischemia. In a stroke that starts out as subarachnoid hemorrhage caused by an aneurysm, white ischemic strokes can occur 4 to 14 days after the aneurysm bursts. This is a time when the blood around the brain irritates the brain’s blood vessels and they clamp shut. Blood flow stops and ischemic stroke can result. This is of course bad news for someone who has just started to recover from the bleeding.
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For Dummies is a registered trademark of Wiley Publishing, Inc. in the United States and other countries. Used here by license.