Also known as Cerebrovascular accident
A stroke occurs if the flow of oxygen-rich blood to a portion of the brain is blocked. Without oxygen, brain cells start to die after a few minutes. Sudden bleeding in the brain also can cause a stroke if it damages brain cells.
If brain cells die or are damaged because of a stroke, symptoms occur in the parts of the body that these brain cells control. Examples of stroke symptoms include sudden weakness; paralysis or numbness of the face, arms, or legs (paralysis is an inability to move); trouble speaking or understanding speech; and trouble seeing.
If you think you or someone else is having a stroke, call the doctor right away. Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room. During a stroke, every minute counts.
A hemorrhagic stroke occurs if an artery in the brain leaks blood or ruptures (breaks open). The pressure from the leaked blood damages brain cells. High blood pressure and aneurysms (AN-u-risms) are examples of conditions that can cause hemorrhagic strokes. (Aneurysms are balloon-like bulges in an artery that can stretch and burst.)
Another condition that's similar to a stroke is a transient ischemic attack, also called a TIA or "mini-stroke." A TIA occurs if blood flow to a portion of the brain is blocked only for a short time. Thus, damage to the brain cells isn't permanent (lasting).
Like ischemic strokes, TIAs often are caused by blood clots. Although TIAs are not full-blown strokes, they greatly increase the risk of having a stroke. If you have a TIA, it's important for your doctor to find the cause so you can take steps to prevent a stroke.
Both strokes and TIAs require emergency care.
Stroke is a leading cause of death in the United States. Many factors can raise your risk of having a stroke. Talk with your doctor about how you can control these risk factors and help prevent a stroke.
In an embolic stroke, a blood clot or other substance (such as plaque, a fatty material) travels through the bloodstream to an artery in the brain. (A blood clot or piece of plaque that travels through the bloodstream is called an embolus.)
In a subarachnoid hemorrhage, a blood vessel on the surface of the brain leaks blood or ruptures. When this happens, bleeding occurs between the inner and middle layers of the membranes that cover the brain.
An ischemic stroke or transient ischemic attack (TIA) occurs if an artery that supplies oxygen-rich blood to the brain becomes blocked. Many medical conditions can increase the risk of ischemic stroke or TIA.
For example, atherosclerosis (ath-er-o-skler-O-sis) is a disease in which a fatty substance called plaque builds up on the inner walls of the arteries. Plaque hardens and narrows the arteries, which limits the flow of blood to tissues and organs (such as the heart and brain).
Plaque in an artery can crack or rupture (break open). Blood platelets (PLATE-lets), which are disc-shaped cell fragments, stick to the site of the plaque injury and clump together to form blood clots. These clots can partly or fully block an artery.
Plaque can build up in any artery in the body, including arteries in the heart, brain, and neck. The two main arteries on each side of the neck are called the carotid (ka-ROT-id) arteries. These arteries supply oxygen-rich blood to the brain, face, scalp, and neck.
An embolic stroke (a type of ischemic stroke) or TIA also can occur if a blood clot or piece of plaque breaks away from the wall of an artery. The clot or plaque can travel through the bloodstream and get stuck in one of the brain's arteries. This stops blood flow through the artery and damages brain cells.
Heart conditions and blood disorders also can cause blood clots that can lead to a stroke or TIA. For example, atrial fibrillation (A-tre-al fi-bri-LA-shun), or AF, is a common cause of embolic stroke.
In AF, the upper chambers of the heart contract in a very fast and irregular way. As a result, some blood pools in the heart. The pooling increases the risk of blood clots forming in the heart chambers.
"Blood pressure" is the force of blood pushing against the walls of the arteries as the heart pumps blood. If blood pressure rises and stays high over time, it can damage the body in many ways.
Aneurysms are balloon-like bulges in an artery that can stretch and burst. AVMs are tangles of faulty arteries and veins that can rupture within the brain. High blood pressure can increase the risk of hemorrhagic stroke in people who have aneurysms or AVMs.
The more risk factors you have, the more likely you are to have a stroke. You can treat or control some risk factors, such as high blood pressure and smoking. Other risk factors, such as age and gender, you can't control.
The major risk factors for stroke include:
High blood pressure is the main risk factor for stroke. Blood pressure is considered high if it stays at or above 140/90 millimeters of mercury (mmHg) over time. If you have diabetes or chronic kidney disease, high blood pressure is defined as 130/80 mmHg or higher.
Diabetes is a disease in which the blood sugar level is high because the body doesn't make enough insulin or doesn't use its insulin properly. Insulin is a hormone that helps move blood sugar into cells where it's used for energy.
Smoking can damage blood vessels and raise blood pressure. Smoking also may reduce the amount of oxygen that reaches your body's tissues. Exposure to secondhand smoke also can damage the blood vessels.
Your risk of stroke increases as you get older. At younger ages, men are more likely than women to have strokes. However, women are more likely to die from strokes. Women who take birth control pills also are at slightly higher risk of stroke.
Strokes occur more often in African American, Alaska Native, and American Indian adults than in white, Hispanic, or Asian American adults.
If you've had a stroke, you're at higher risk for another one. Your risk of having a repeat stroke is the highest right after a stroke. A TIA also increases your risk of having a stroke, as does having a family history of stroke.
Aneurysms are balloon-like bulges in an artery that can stretch and burst. AVMs are tangles of faulty arteries and veins that can rupture (break open) within the brain. AVMs may be present at birth, but often aren't diagnosed until they rupture.
Other risk factors for stroke, many of which of you can control, include:
Following a heart-healthy lifestyle can lower the risk of stroke. Some people also may need to take medicines to lower their risk. Sometimes strokes can occur in people who don't have any known risk factors.
Taking action to control your risk factors can help prevent or delay a stroke. If you've already had a stroke. Talk to your doctor about whether you may benefit from aspirin primary prevention, or using aspirin to help prevent your first stroke. The following heart-healthy lifestyle changes can help prevent your first stroke and help prevent you from having another one.
If you or someone in your family has had a stroke, be sure to tell your doctor. By knowing your family history of stroke, you may be able to lower your risk factors and prevent or delay a stroke. If you've had a transient ischemic attack (TIA), don't ignore it. TIAs are warnings, and it's important for your doctor to find the cause of the TIA so you can take steps to prevent a stroke.
The signs and symptoms of a stroke often develop quickly. However, they can develop over hours or even days.
The type of symptoms depends on the type of stroke and the area of the brain that's affected. How long symptoms last and how severe they are vary among different people.
Signs and symptoms of a stroke may include:
A transient ischemic attack (TIA) has the same signs and symptoms as a stroke. However, TIA symptoms usually last less than 1–2 hours (although they may last up to 24 hours). A TIA may occur only once in a person's lifetime or more often.
If you think you or someone else is having a TIA or stroke, call the doctor right away. Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room. During a stroke, every minute counts.
After you've had a stroke, you may develop other complications, such as:
Your doctor will diagnose a stroke based on your signs and symptoms, your medical history, a physical exam, and test results.
Your doctor will ask you or a family member about your risk factors for stroke. Examples of risk factors include high blood pressure, smoking, heart disease, and a personal or family history of stroke. Your doctor also will ask about your signs and symptoms and when they began.
During the physical exam, your doctor will check your mental alertness and your coordination and balance. He or she will check for numbness or weakness in your face, arms, and legs; confusion; and trouble speaking and seeing clearly.
Your doctor will look for signs of carotid artery disease, a common cause of ischemic stroke. He or she will listen to your carotid arteries with a stethoscope. A whooshing sound called a bruit (broo-E) may suggest changed or reduced blood flow due to plaque buildup in the carotid arteries.
A brain computed tomography (to-MOG-rah-fee) scan, or brain CT scan, is a painless test that uses x rays to take clear, detailed pictures of your brain. This test often is done right after a stroke is suspected.
Magnetic resonance imaging (MRI) uses magnets and radio waves to create pictures of the organs and structures in your body. This test can detect changes in brain tissue and damage to brain cells from a stroke.
An MRI may be used instead of, or in addition to, a CT scan to diagnose a stroke.
A CT arteriogram (CTA) and magnetic resonance arteriogram (MRA) can show the large blood vessels in the brain. These tests may give your doctor more information about the site of a blood clot and the flow of blood through your brain.
Carotid ultrasound is a painless and harmless test that uses sound waves to create pictures of the insides of your carotid arteries. These arteries supply oxygen-rich blood to your brain.
Your carotid ultrasound test may include a Doppler ultrasound. Doppler ultrasound is a special test that shows the speed and direction of blood moving through your blood vessels.
Carotid angiography (an-jee-OG-ra-fee) is a test that uses dye and special x rays to show the insides of your carotid arteries.
For this test, a small tube called a catheter is put into an artery, usually in the groin (upper thigh). The tube is then moved up into one of your carotid arteries.
Your doctor will inject a substance (called contrast dye) into the carotid artery. The dye helps make the artery visible on x-ray pictures.
An EKG is a simple, painless test that records the heart's electrical activity. The test shows how fast the heart is beating and its rhythm (steady or irregular). An EKG also records the strength and timing of electrical signals as they pass through each part of the heart.
An EKG can help detect heart problems that may have led to a stroke. For example, the test can help diagnose atrial fibrillation or a previous heart attack.
Echocardiography (EK-o-kar-de-OG-ra-fee), or echo, is a painless test that uses sound waves to create pictures of your heart.
The test gives information about the size and shape of your heart and how well your heart's chambers and valves are working.
Echo can detect possible blood clots inside the heart and problems with the aorta. The aorta is the main artery that carries oxygen-rich blood from your heart to all parts of your body.
Your doctor also may use blood tests to help diagnose a stroke.
A blood glucose test measures the amount of glucose (sugar) in your blood. Low blood glucose levels may cause symptoms similar to those of a stroke.
A platelet count measures the number of platelets in your blood. Blood platelets are cell fragments that help your blood clot. Abnormal platelet levels may be a sign of a bleeding disorder (not enough clotting) or a thrombotic disorder (too much clotting).
Your doctor also may recommend blood tests to measure how long it takes for your blood to clot. Two tests that may be used are called PT and PTT tests. These tests show whether your blood is clotting normally.
Treatment for a stroke depends on whether it is ischemic or hemorrhagic. Treatment for a transient ischemic attack (TIA) depends on its cause, how much time has passed since symptoms began, and whether you have other medical conditions.
Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin lifesaving treatment on the way to the emergency room. During a stroke, every minute counts.
An ischemic stroke or TIA occurs if an artery that supplies oxygen-rich blood to the brain becomes blocked. Often, blood clots cause the blockages that lead to ischemic strokes and TIAs. Treatment for an ischemic stroke or TIA may include medicines and medical procedures.
If you have a stroke caused by a blood clot, you may be given a clot-dissolving, or clot-busting, medication called tissue plasminogen activator (tPA). A doctor will inject tPA into a vein in your arm.
This type of medication must be given within 4 hours of symptom onset. Ideally, it should be given as soon as possible. The sooner treatment begins, the better your chances of recovery. Thus, it's important to know the signs and symptoms of a stroke.
If you can't have tPA for medical reasons, your doctor may give you antiplatelet medicine that helps stop platelets from clumping together to form blood clots or anticoagulant medicine (blood thinner) that keeps existing blood clots from getting larger. Two common medicines are aspirin and clopidogrel.
If you have carotid artery disease, your doctor may recommend a carotid endarterectomy or carotid artery angioplasty. Both procedures open blocked carotid arteries.
Researchers are testing other treatments for ischemic stroke, such as intra-arterial thrombolysis and mechanical clot removal in cerebral ischemia (MERCI).
In intra-arterial thrombolysis, a long flexible tube called a catheter is put into your groin (upper thigh) and threaded to the tiny arteries of the brain. Your doctor can deliver medicine through this catheter to break up a blood clot in the brain.
MERCI is a device that can remove blood clots from an artery. During the procedure, a catheter is threaded through a carotid artery to the affected artery in the brain. The device is then used to pull the blood clot out through the catheter.
A hemorrhagic stroke occurs if an artery in the brain leaks blood or ruptures. The first steps in treating a hemorrhagic stroke are to find the cause of bleeding in the brain and then control it. Unlike ischemic strokes, hemorrhagic strokes aren't treated with antiplatelet medicines and blood thinners because these medicines can make bleeding worse.
If you're taking antiplatelet medicines or blood thinners and have a hemorrhagic stroke, you'll be taken off the medicine. If high blood pressure is the cause of bleeding in the brain, your doctor may prescribe medicines to lower your blood pressure. This can help prevent further bleeding.
Aneurysm clipping is done to block off the aneurysm from the blood vessels in the brain. This surgery helps prevent further leaking of blood from the aneurysm. It also can help prevent the aneurysm from bursting again.
During the procedure, a surgeon will make an incision (cut) in the brain and place a tiny clamp at the base of the aneurysm. You'll be given medicine to make you sleep during the surgery. After the surgery, you'll need to stay in the hospital's intensive care unit for a few days.
Coil embolization is a less complex procedure for treating an aneurysm. The surgeon will insert a tube called a catheter into an artery in the groin. He or she will thread the tube to the site of the aneurysm. Then, a tiny coil will be pushed through the tube and into the aneurysm.
The coil will cause a blood clot to form, which will block blood flow through the aneurysm and prevent it from bursting again. Coil embolization is done in a hospital. You'll be given medicine to make you sleep during the surgery.
If an AVM is the cause of a stroke, your doctor may recommend an AVM repair. (An AVM is a tangle of faulty arteries and veins that can rupture within the brain.) AVM repair helps prevent further bleeding in the brain.
Doctors use several methods to repair AVMs. These methods include:
Heart-healthy lifestyle changes may include:
If heart-healthy lifestyle changes aren't enough, you may need medicine to control your risk factors.
Do not drive to the hospital or let someone else drive you. By calling an ambulance, medical personnel can begin lifesaving treatment on the way to the emergency room. During a stroke, every minute counts.
Heart-healthy lifestyle changes can help you recover from a stroke and may help prevent another one. Examples of these changes include heart-healthy eating, aiming for a healthy weight, managing stress, physical activity, and quitting smoking.
Your doctor also may prescribe medicines to help you recover from a stroke or control your stroke risk factors. Take all of your medicines as your doctor prescribes. Don't cut back on the dosage unless your doctor tells you to do so. If you have side effects or other problems related to your medicines, talk with your doctor.
Medicines called anticoagulants or blood thinners, which prevent blood clots or keep existing blood clots from getting larger, are the main treatment for people who have known carotid artery disease, which can lead to a stroke. Two common medicines are aspirin and clopidogrel.
You'll likely need routine blood tests to check how well these medicines are working.
The most common side effect of blood thinners is bleeding. This happens if the medicine thins your blood too much. This side effect can be life-threatening. Bleeding can occur inside your body cavities (internal bleeding) or from the surface of your skin (external bleeding).
Know the warning signs of bleeding so you can get help right away. They include:
A lot of bleeding after a fall or injury or easy bruising or bleeding also may mean that your blood is too thin. Call your doctor right away if you have any of these signs.
Your doctor also may discuss beginning statin treatment. Doctors recommend statin medications for many people because they help lower or control blood cholesterol levels and decrease the chance for heart attack and stroke. Doctors usually prescribe statins for people who have:
You should still follow a heart-healthy lifestyle, even if you take medicines to control your risk factors for stroke. Take all medicines regularly, as your doctor prescribes. Don't change the amount of your medicine or skip a dose unless your doctor tells you to.
Talk with your doctor about how often you should schedule follow-up visits or tests. These visits and tests can help your doctor monitor your stroke risk factors and adjust your treatment as needed.
You may have trouble communicating after a stroke. You may not be able to find the right words, put complete sentences together, or put words together in a way that makes sense. You also may have problems with your memory and thinking clearly. These problems can be very frustrating.
Speech and language therapists can help you learn ways to communicate again and improve your memory.
A stroke may affect only one side of the body or part of one side. It can cause paralysis (an inability to move) or muscle weakness, which can put you at risk for falling. Physical and occupational therapists can help you strengthen and stretch your muscles. They also can help you relearn how to do daily activities, such as dressing, eating, and bathing.
A stroke can affect the muscles and nerves that control the bladder and bowels. You may feel like you have to urinate often, even if your bladder isn't full. You may not be able to get to the bathroom in time. Medicines and a bladder or bowel specialist can help with these problems.
You may have trouble swallowing after a stroke. Signs of this problem are coughing or choking during eating or coughing up food after eating. A speech therapist can help you with these issues. He or she may suggest changes to your diet, such as eating puréed (finely chopped) foods or drinking thick liquids.
After a stroke, you may have changes in your behavior or judgment. For example, your mood may change quickly. Because of these and other changes, you may feel scared, anxious, and depressed. Recovering from a stroke can be slow and frustrating.
Talk about how you feel with your health care team. Talking to a professional counselor also can help. If you're very depressed, your doctor may recommend medicines or other treatments that can improve your quality of life.
Joining a patient support group may help you adjust to life after a stroke. You can see how other people have coped with having strokes. Talk with your doctor about local support groups, or check with an area medical center.
Support from family and friends also can help relieve fear and anxiety. Let your loved ones know how you feel and what they can do to help you.