A stroke is a sudden episode that occurs when the blood supply to part of the brain is interrupted or when a blood vessel in the brain bursts, spilling blood into the spaces surrounding brain cells. Risk factors include such things as having high blood pressure, smoking, and having a family history of stroke. Symptoms of a stroke typically occur suddenly and can include confusion, dizziness, severe headache, and numbness or weakness in the limbs or face. Treatment options may include medications, surgery, and rehabilitation.
A stroke is a sudden episode that may affect consciousness, sensation, and movement, which results from a blockage or rupture of a blood vessel in the brain. It causes symptoms that last for at least 24 hours. A stroke (known medically as a cerebrovascular accident or CVA) occurs when the blood supply to part of the brain is suddenly interrupted or when a blood vessel in the brain bursts, spilling blood into the spaces surrounding brain cells. Brain cells die when they no longer receive oxygen and nutrients from the blood or there is sudden bleeding into or around the brain.
There are two main types -- ischemic and hemorrhagic. The ischemic type occurs when there is a lack of oxygen- or nutrient-rich blood to a part of the brain for a long enough period of time that brain tissue dies. This lack of blood flow occurs because of a severely narrowed or blocked artery in the neck or brain. The ischemic type makes up 80 percent of all cases.
The second type is a hemorrhagic stroke. This type occurs because of bleeding in the brain from a broken blood vessel. For each type -- ischemic and hemorrhagic -- the causes can vary.
Risk factors are conditions or behaviors that increase your chances of getting a certain disease. Some risk factors can be treated or controlled, and some cannot.
Risk factors for this condition that you cannot change include:
Age (the risk tends to increase with age)
Gender (men are more likely to have a stroke, but women are more likely to die of one)
Race/ethnicity (African Americans are more likely to have a stroke than people from other ethnic groups)
Family history of stroke
Personal history of a stroke, TIA, or heart attack.
Some of the most important treatable or controllable risk factors are:
High blood pressure (hypertension)
Smoking
High cholesterol (hypercholesterolemia)
Atrial fibrillation
Certain heart diseases
Diabetes
Carotid artery disease
Sleep apnea
Heavy consumption of alcohol
Drug abuse.
Some of the signs and symptoms of a stroke may include sudden difficulty speaking or understanding speech, confusion, and numbness or weakness in the face or limbs (especially on one side of the body). Other symptoms associated with a stroke can include dizziness, loss of balance, and vomiting. In general, symptoms appear suddenly; often, multiple symptoms are present at the same time. Call 911 immediately if you suspect that you or someone else is having a stroke.
Even though a stroke occurs in the unseen reaches of the brain, symptoms of a stroke can be easy to spot. As a general rule, symptoms with a stroke appear suddenly, and often there is more than one symptom present at the same time. Therefore, a stroke can usually be distinguished from other causes of dizziness or headache. The signs and symptoms discussed below may indicate that a person has had a stroke and requires medical attention immediately.
For a person having a stroke, the symptoms may vary depending on which part of the brain is affected. Examples of specific symptoms can include:
Sudden numbness or weakness of face, arm, hand, or leg (especially on one side of the body)
Sudden confusion
Sudden trouble speaking or understanding speech
Sudden trouble seeing in one or both eyes (such as double vision, blurred vision, or blindness)
Sudden dizziness, lightheadedness, or trouble walking
Sudden loss of balance or coordination
Sudden severe headache with no known cause
Vomiting
Loss of consciousness
Spinning sensation (vertigo)
Sudden collapse
Seizures (in a small number of cases).
Seek immediate medical attention if you notice any signs or symptoms of a stroke, even if they seem to fluctuate or disappear. Do not wait for the symptoms to worsen or improve. Call 911 immediately. Don't wait to see if symptoms go away. The longer a stroke goes untreated, the greater the potential for brain damage and disability. To maximize the effectiveness of evaluation and treatment, it's best that you get to the emergency room within 60 minutes of your first symptoms.
There are now effective therapies for stroke that need to be administered at a hospital; however, they lose their effectiveness if they are not received within the first three hours after stroke-related symptoms appear.
Also, keep in mind that it is common for a stroke victim to protest or deny that he or she is having a stroke. If you notice a person exhibiting any of the possible symptoms of a stroke discussed above, get help right away.
If you're with someone you suspect is having a stroke, watch the person carefully while waiting for emergency assistance. You may need to:
Begin mouth-to-mouth resuscitation if the person stops breathing
Turn the person's head to the side if vomiting occurs, which can prevent choking
Keep the person from eating or drinking
Strokes are usually diagnosed by studying images of the brain (brain imaging). This can also be helpful in determining the risk of a transient ischaemic attack (TIA).
Even if the physical symptoms of a stroke are obvious, brain imaging should be carried out to determine:
if the stroke has been caused by a blocked artery or a burst blood vessel
which part of the brain has been affected
how severe the stroke is
Different treatment is required for each type of stroke so a rapid diagnosis will make treatment more straightforward.
Two common methods used for brain imaging are a computer tomography (CT) scan and a magnetic resonance imaging (MRI) scan.
A CT scan is like an X-ray but it uses multiple images to build up a more detailed, three-dimensional (3D) picture of your brain. An MRI scan uses a strong magnetic field and radio waves to produce a detailed picture of the inside of your body.
The type of scan you may have in hospital depends on the type of symptoms. In people with suspected major stroke, a CT scan is sufficient to identify whether the stroke is due to bleeding or clotting. It's quicker than an MRI scan and improves the chances of rapidly delivering treatments such as clot-busting (thrombolysis) that might be used in appropriate cases but which are time-limited and require the results of the scan before the treatment can be given safely.
For people with more complex symptoms, where the extent or location of the damage is unknown, and in patients who have recovered from a transient ischaemic attack, an MRI scan is more appropriate. This will provide greater detail of brain tissue, allowing smaller, or more unusually located strokes to be identified.
All patients with suspected stroke should receive a brain scan within 24 hours. Some patients should be scanned within the hour, especially those who:
have had a suspected thrombotic stroke and might benefit from clot-busting drugs (thrombolysis) such as alteplase or early anticoagulant treatment
are already on anticoagulant treatments
have a lower level of consciousness
After the injection of a dye into an arm vein, both CT and MRI can be used to take pictures of the blood vessels in the brain, as well as the blood vessels in the neck that take blood to the brain from the heart. This is known as a CT or MR angiogram and is often done immediately after taking picture of the brain itself.
A swallow test is essential for anybody who has had a stroke.
Swallowing problems affect over a third of people after a stroke. When a person cannot swallow properly, there is a risk that food and drink may get into the windpipe and then into the lungs (called aspiration), which can lead to chest infections and pneumonia.
The test is simple. The person is given a few teaspoons of water to drink. If they can swallow this without choking and coughing they will be asked to swallow half a glass of water.
If they have any difficulty swallowing, they will be referred to the speech and language therapist for a more detailed assessment. They will usually be kept from food and water until they have seen the therapist and may therefore need to have fluids or food given by an intravenous drip or nasogastric tube.
Further tests on the heart and blood vessels might be carried out later to confirm what caused the stroke. These may include:
Ultrasound (carotid ultrasonography)
An ultrasound scan uses high frequency sound waves to produce an image of the inside of your body. Your doctor may use a wand-like probe (transducer) to send high-frequency sound waves into your neck. These pass through the tissue creating images on a screen that will show if there is any narrowing or clotting in the arteries leading to your brain.
This type of ultrasound scan is sometimes known as a doppler scan or a duplex scan. Where carotid ultrasonography is needed, it should happen within 48 hours.
Catheter angiography (arteriography)
Dye is injected into your carotid or vertebral artery via a catheter. This gives a detailed view of your arteries than can be obtained using ultrasound, CT angiography or MR angiography.
Echocardiogram
In some cases an echocardiogram may be used to produce images of your heart using an ultrasound probe placed on your chest (transthoracic echocardiogram). In addition, transoesophageal echocardiography (TOE) may also be used. This involves an ultrasonic probe which is passed down the foodpipe (oesophagus), usually under sedation. Because it's directly behind the heart, it produces a clear image of blood clots and other abnormalities that may not get picked up by the transthoracic echocardiogram.
Physical examination
Your doctor may check for risk factors of stroke by taking blood tests, checking your pulse and blood pressure and using a stethoscope to listen to the sound of blood in the neck arteries.
Each year, about 700,000 people in the United States have a stroke. Over 150,000 of these people die as a result, making it the third most common cause of death in the U.S. Delaying treatment can result in lasting damage to your brain, or even death. The sooner treatment begins, the better your chances of recovering.
Treatment options for a stroke may include medications, surgery, and stroke rehabilitation. For people who have had an ischemic stroke, it may involve the use of thrombolytic ("clot-busting") drugs to dissolve blood clots that are blocking blood flow to the brain. Other medicine that doctors may use to treat a stroke may include anticoagulants and antiplatelets. After a stroke survivor has left the hospital, treatment often continues in the form of rehabilitation. Lifestyle changes are often part of long-term treatment following a stroke.
The goals of stroke treatment are to:
Quickly restore blood flow to the brain (in those people with an ischemic stroke) or stop the bleeding (in those people with hemorrhagic stroke)
Continuously monitor vital signs to detect and treat stroke complications
Make lifelong changes to reduce the chances of another stroke.
Depending on the situation and the type of stroke (ischemic versus hemorrhagic stroke), specific treatment options may include:
Medications, such as thrombolytic ("clot-busting") drugs
Surgery
Stroke rehabilitation and lifestyle changes.
The following sections explain in detail how the treatment goals for stroke are achieved.
Ischemic Stroke (Restore Blood Flow)
For people with an ischemic stroke (which accounts for 80 percent of stroke cases), restoring blood flow to the brain is vital to prevent or limit damage to the brain tissue and to prevent another stroke. Brain cells die quickly when they do not receive oxygen- or nutrient-rich blood. The main treatments used to restore blood flow to the heart involve thrombolytic drugs.
Healthcare providers may prescribe thrombolytic ("clot-busting") drugs to dissolve blood clots that are blocking blood flow to the brain. When given soon after an ischemic stroke begins, these drugs can limit or prevent permanent damage to the brain by dissolving the blood clot. In treating a stroke that has just occurred, every minute counts. Get a person who has had a stroke to the hospital as soon as possible after stroke symptoms start so he or she may be evaluated and receive treatment as soon as possible.
A thrombolytic drug known as tissue plasminogen activator (t-PA, Activase) can be effective for treating a stroke if a person receives it within three hours after his or her stroke symptoms have started. Because thrombolytic drugs can increase bleeding, doctors only use t-PA when they are certain that the person has suffered an ischemic stroke and not a hemorrhagic stroke.
Hemorrhagic Stroke (Stop the Bleeding)
In people with a hemorrhagic stroke, treatment options will depend on what is causing the bleeding. The key with this type of treatment is to stop the bleeding as quickly as possible. Surgery may be one option. For example, in people with a brain aneurysm that that has bled, healthcare providers may recommend a technique called "clipping." Clipping involves clamping off the aneurysm from the blood vessel, which reduces the chance that it will burst and bleed.
The detachable coil technique is a new therapy for treating high-risk intracranial aneurysms, or aneurysms that occur inside the skull. Doctors insert a small platinum coil through an artery in the thigh and thread it through the arteries to the site of the aneurysm. They then release the coil into the aneurysm, where it triggers an immune response from the body. This immune response causes a blood clot to form inside the aneurysm, strengthening the artery walls and reducing the risk of rupture. Once the aneurysm is stabilized, a neurosurgeon can clamp it off with less risk of bleeding and death to the patient.
In addition to treatments to restore blood flow in people who have suffered an ischemic stroke, healthcare providers may use other medications or therapies as part of stroke treatment to reduce complications or the chances of another stroke. Some of these medicines can include:
Anticoagulants
Antiplatelets.
Anticoagulants
Anticoagulants reduce the risk of another stroke by decreasing the ability for blood to clot and also prevent existing clots from growing. These drugs are particularly useful in preventing the formation of clots in people with atrial fibrillation. The most commonly used anticoagulants for stroke treatment include warfarin (Coumadin), heparin, and enoxaparin (Lovenox).
Antiplatelets
Antiplatelet drugs prevent clotting by decreasing the activity of platelets, which are blood cells that help blood clot. By reducing the risk of blood clots, these drugs lower the risk of ischemic stroke. In the case of stroke treatment, doctors prescribe antiplatelet drugs mainly for prevention of another stroke. The most widely known and used antiplatelet drug is aspirin. Other antiplatelet drugs include:
Clopidogrel (Plavix)
Ticlopidine (Ticlid)
Dipyridamole (Persantine)
Aspirin and dipyridamole (Aggrenox).
Treatment for a stroke does not end when a person leaves the hospital. In fact, leaving the hospital is when treatment really begins in many cases. For a lot of people who have had a stroke, treatment is a lifelong process.
When it is time to leave the hospital, you will likely receive:
Specific dietary and rehabilitation instructions
Discharge instructions concerning driving, activity level, and medication
Any other restrictions.
Healthcare providers will also go over any symptoms that require immediate medical attention. For people recovering from a stroke, the most important post-stroke treatments include:
Stroke rehabilitation (stroke rehab for short)
Losing weight, if you are overweight or obese.
Eating a healthy diet to prevent or lower blood pressure and blood cholesterol.
Lifestyle changes, which may include quitting smoking, changing your diet, and increasing your physical activity
Medications used to help prevent blood from clotting or to control stroke risk factors, such as high blood pressure and atrial fibrillation.
A surgery or procedure to help decrease the chances of another stroke.
Exercising as directed by your doctor. Exercise is good for your overall health. It can help you lose weight, keep your cholesterol and blood pressure under control, reduce stress, and lift your mood.
Knowing your stroke risk factors, following your doctor's recommendations and adopting a healthy lifestyle are the best steps you can take to prevent a stroke. If you've had a stroke or a TIA, these measures may also help you avoid having another one. Many stroke prevention strategies are the same as for preventing heart disease. In general, a healthy lifestyle means that you:
Control high blood pressure (hypertension). One of the most important things you can do to reduce your stroke risk is to keep your blood pressure under control. If you've had a stroke, lowering your blood pressure can help prevent a subsequent transient ischemic attack or stroke. Exercising, managing stress, maintaining a healthy weight, and limiting the amount of sodium and alcohol you eat and drink are all ways to keep high blood pressure in check. Adding more potassium to your diet may also help. In addition to recommendations for lifestyle changes, your doctor may prescribe medications to treat high blood pressure, such as diuretics, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers.
Lower the amount of cholesterol and saturated fat in your diet. Eating less cholesterol and fat, especially saturated fat and trans fats, may reduce the plaques in your arteries. If you can't control your cholesterol through dietary changes alone, your doctor may prescribe a statin such as simvastatin (Zocor) or atorvastatin (Lipitor) or another type of cholesterol-lowering medication.
Don't smoke. Smoking raises the risk of stroke for both the smoker and nonsmokers exposed to secondhand smoke. Quitting smoking reduces your risk — several years after quitting, a former smoker's risk of stroke is the same as that of a nonsmoker.
Control diabetes. You can manage diabetes with diet, exercise, weight control and medication.
Maintain a healthy weight. Being overweight contributes to other risk factors for stroke, such as high blood pressure, cardiovascular disease and diabetes. Weight loss of as little as 10 pounds may lower your blood pressure and improve your cholesterol levels.
Eat a diet rich in fruits and vegetables. A diet containing five or more daily servings of fruits or vegetables may reduce your risk of stroke.
Exercise regularly. Aerobic exercise reduces your risk of stroke in many ways. Exercise can lower your blood pressure, increase your level of high-density lipoprotein (HDL, or "good") cholesterol, and improve the overall health of your blood vessels and heart. It also helps you lose weight, control diabetes and reduce stress. Gradually work up to 30 minutes of activity — such as walking, jogging, swimming or bicycling — on most, if not all, days of the week.
Drink alcohol in moderation, if at all. Alcohol can be both a risk factor and a preventive measure for stroke. Binge drinking and heavy alcohol consumption increase your risk of high blood pressure and of ischemic and hemorrhagic strokes. However, drinking small to moderate amounts of alcohol can increase your HDL cholesterol and decrease your blood's clotting tendency. Both factors can contribute to a reduced risk of ischemic stroke.
Don't use drugs. Certain street drugs, such as cocaine and methamphetamines, are established risk factors for a TIA or a stroke.
If you've had an ischemic stroke or TIA, your doctor may recommend medications to help reduce your risk of having another. These include:
Anti-platelet drugs. Platelets are cells in your blood that initiate clots. Anti-platelet drugs make these cells less sticky and less likely to clot. The most frequently used anti-platelet medication is aspirin. Your doctor can help you determine the right dose of aspirin for you.
Your doctor may also consider prescribing Aggrenox, a combination of low-dose aspirin and the anti-platelet drug dipyridamole, to reduce blood clotting. If aspirin doesn't prevent your TIA or stroke or if you can't take aspirin, your doctor may instead prescribe an anti-platelet drug such as clopidogrel (Plavix) or ticlopidine (Ticlid).
Anticoagulants. These drugs include heparin and warfarin (Coumadin). They affect the clotting mechanism in a different manner than do anti-platelet medications. Heparin is fast acting and is used over the short term in the hospital. Slower acting warfarin is used over a longer term.
Warfarin is a powerful blood-thinning drug, so you'll need to take it exactly as directed and watch for side effects. Your doctor may prescribe these drugs if you have certain blood-clotting disorders; certain arterial abnormalities; an abnormal heart rhythm, such as atrial fibrillation: or other heart problems.