A stroke occurs when blood flow to a part of the brain is impaired, either because the arteries have become constricted due to atherosclerosis or because of bleeding in the brain. Within minutes, the nerve cells in the affected area of the brain become damaged and die.
If you, or someone you are with, experience symptoms of stroke, call 911 and seek care immediately at the closest emergency room.
- Don't wait. Stroke is an emergency, just like a heart attack. It is important that you seek medical attention immediately. Prompt treatment may reverse the effects of the stroke, prevent death, and prevent disabilities.
- The sooner you are treated, the better your outcome is likely to be.
Stroke is the third leading cause of death in the United States and the primary cause of adult disability. Up to 80 percent of strokes are preventable. In recent years, fewer people have died of stroke because we have more sophisticated means of identifying and controlling your risk factors. We can work closely with you to help reduce risk factors associated with stroke.
Know the Warning Signs of Stroke
If you are with someone who may be having a stroke, follow these steps:
- Ask the person to smile. Does one side of the face droop?
- Ask the person to raise both arms. Does one arm drift downward?
- Ask the person to repeat a simple sentence. Are the words slurred? Can he or she repeat the sentence correctly?
If the person shows any of these symptoms, time is important. Call 911 or get to the hospital fast. Brain cells are dying.
There are 2 major types of stroke. The first is known as ischemic stroke and is caused by insufficient blood flow due to a clot. The second is caused by bleeding in the brain and is known as a hemorrhagic stroke. Ischemic strokes are more common, accounting for approximately 80 percent of all cases. Hemorrhagic strokes can be more dangerous, however. There are some additional basic facts about the 2 types of strokes:
- Atherosclerosis, or hardening of the arteries, is the most common cause of strokes.
- The hardening is caused by cholesterol plaques that develop within the blood vessel wall and eventually block the artery or cause the spontaneous formation of a blood clot.
- If your artery remains blocked for more than a few minutes, brain cells may die. This is why immediate medical treatment is absolutely critical.
- Several risk factors for atherosclerosis have been identified, including high blood pressure, elevated cholesterol, diabetes, smoking, and advanced age.
- Hemorrhagic stroke occurs when a blood vessel bursts inside the brain.
- The blood irritates the brain tissue, causing swelling, and collects into a mass called a hematoma.
- In some instances, urgent surgery is required to evacuate or drain the blood to preserve the surrounding brain tissue.
- Poorly controlled high blood pressure is the most common cause of hemorrhagic stroke.
Stroke symptoms begin suddenly and can include:
- Weakness or numbness on one side of the body
- Confusion, slurring of speech, difficulty finding the correct words to say, or a complete inability to talk
- Changes in vision, such as partial or complete blindness or seeing double
- Trouble walking, vertigo or dizziness, loss of balance or coordination
- Severe sudden headache (with hemorrhagic strokes)
Transient ischemic attack (TIA)
A transient ischemic attack (TIA) is a serious emergency condition, because it can be a warning sign of a future stroke. TIAs occur when hardening of the arteries (atherosclerosis) temporarily interferes with blood flow to a part of the brain. TIAs are often called ministrokes, which is inaccurate. Unlike ministrokes, the symptoms of TIAs do not usually leave permanent damage.
Here are some things to remember about a TIA:
- If the symptoms are short-term, lasting a few minutes or hours, they may be referred to as a TIA.
- If you experience a TIA, seek help immediately because you are at greater risk for a full-blown ischemic stroke.
- Unlike ischemic stroke symptoms, TIA symptoms usually disappear within 10 to 20 minutes, although they may last longer.
- If you have a TIA, you need emergency medical care. Remember: A TIA is a warning signal that a stroke may soon occur, and you have a limited period of time in which to prevent it.
Stroke is an emergency condition. If you have symptoms, call 911 or go to the nearest Emergency Room.
In the Emergency Room
- We will examine you to assess the scope and effects of the stroke.
- We will review your history and medical records and ask you about the onset of your symptoms. If you are unable to communicate, we will try to gather this information by talking to a family member or friend.
- We will perform diagnostic tests as appropriate, including blood tests, an electrocardiogram (EKG or ECG), and a CT (computed tomography) scan. We may also perform other tests, including MRI (magnetic resonance imaging), cerebral angiography, carotid ultrasound (carotid doppler or duplex ultrasound), and/or echocardiogram (heart ultrasound).
- We may provide aspirin to reduce the risk of another stroke.
- We may provide a medication called tissue plasminogen activator (tPA) if you are having an acute ischemic stroke. tPA is a clot-busting drug approved for use in some people having a heart attack or ischemic stroke.
- We generally must give tPA within 3 hours of the onset of the stroke for it to be effective. The drug can dissolve blood clots, which cause most heart attacks and strokes.
Once you have been admitted to the hospital
- We will assess whether it is safe for you to swallow. This is important to help prevent infection.
- We will begin to develop a rehabilitation plan for you. This will include evaluating you for any necessary mobility devices and deciding on the most appropriate place for you to continue your rehabilitation.
- We will monitor you for any changes in condition, nutrition, hydration, and other complications.
- We will also work with you to prevent future strokes. This may involve further testing to establish the cause of your stroke.
Treatment depends on the severity and cause of the stroke, although most people who have a stroke will be admitted to the hospital. Many of our hospitals in Northern California are certified by the Joint Commission as "Primary Stroke Centers," meaning that they have undergone and passed rigorous evaluations by a national agency to ensure the highest quality of care.
There are a range of surgical options available for treating a stroke:
Carotid artery surgery (endarterectomy)
- During a carotid endarterectomy, a vascular surgeon removes plaque (fatty deposits) from the carotid arteries in your neck that supply blood to your brain.
- The timing of the surgery will depend on a number of factors, including the extent of brain damage and your overall health.
- If you had a TIA (transient ischemic attack) or ischemic stroke, we recommend surgery when your carotid artery is narrowed by 70 percent, or more, on the side that supplies the area of the brain affected by the TIA.
- If your artery is narrowed by less than 50 to 69 percent after a TIA, treatment to control stroke risk factors with medication appears to be about as effective as surgery.
- If your artery is narrowed by less than 50 percent, we usually recommend medication rather than surgery.
- If you have not had a TIA or ischemic stroke, but you have narrowed carotid arteries, we may recommend surgery in order to prevent strokes. However the benefit is not as dramatic as it is for patients with TIA or ischemic stroke even if the narrowing is severe.
- Since carotid artery surgery is not without risks, we will carefully consider the risks and benefits before considering surgery if you have no symptoms.
Angioplasty and stent replacement
- Angioplasty and stent replacement is a less common procedure for opening arteries that have been narrowed by plaque buildup.
- During the procedure, we place a catheter into an artery in the groin and guide it, via X-ray, to the site of blood vessel narrowing.
- The blood vessel is then dilated with a balloon, and a tiny cylindrical wire mesh (known as a stent) inserted into the artery to keep it open.
- We may recommend this procedure if you have suffered a TIA or have severe carotid artery stenosis and your general health makes you a poor candidate for carotid artery surgery.
- We may also use angioplasty if you have already had carotid artery surgery on a blood vessel and it has narrowed again.
Anticlotting medications are used to reduce the chances of blood clots forming and thus reduce the risk of stroke. These include:
|Drug Name||Used For||Drug Type|
|Clopidogrel||Stroke prevention ||Antiplatelet|
|Dipyridamole||Stroke prevention ||Antiplatelet|
|Heparin ||Stroke prevention ||Anticoagulant|
|Ticlopidine||Stroke prevention ||Antiplatelet|
|Tissue Plasminogen Activator||Acute stroke treatment||Thrombolytic|
|Warfarin||Stroke prevention ||Anticoagulant|
Some stroke medications should not be taken by women who are trying to get pregnant or are at risk for pregnancy because they can cause birth defects. If you are a woman of childbearing age (15 to 49) and are not planning to get pregnant, use an effective form of birth control. You must be using a highly reliable birth control method if you are taking certain medications to prevent stroke.
Everyone can be at risk of stroke. Some risk factors are outside of your control. Others are associated with medical conditions or lifestyle habits. Some of these risk factors can be controlled. If you have one or more modifiable risk factors, we will work closely with you to minimize your risk and prevent a stroke.
Uncontrollable risk factors
- Age. The risk for stroke increases with age and doubles every decade after 55.
- Race. African Americans and Hispanics are at greater risk of stroke compared to other races. Young African Americans are 2 to 3 times more likely to experience ischemic stroke and are more likely to die from stroke compared to Caucasians.
- Gender. Stroke is more common in men than women. However, stroke is more severe in women at all ages, and more women than men die of stroke.
- Family history. You are at greater risk for stroke if you have a parent or sibling who has had a heart attack or stroke.
- Prior history of stroke or TIA. About 14 percent of people who have a stroke have another stroke within 1 year; 25 percent have another stroke within 5 years.
Medical and lifestyle risk factors
If you have suffered a stroke, we will work with you to control or minimize your modifiable risk factors. These controllable risk factors include the following:
- High blood pressure (hypertension).
- High cholesterol.
- Carotid artery disease.
- Atrial fibrillation. This is an abnormal heart rhythm that causes blood clots to form within the heart. These clots can break off and lodge in the blood vessels supplying the brain.
- Other heart conditions, including endocarditis, heart valve conditions, and cardiomyopathy (heart pumping problem).
- Sleep apnea (sleep-related breathing disorder) has recently been linked to increasing risk of stroke.
- Other rarer diseases and conditions, such as lupus, syphilis, hemophilia, pneumonia, high levels of homocysteine, and periodontal disease.
- Use of birth control pills. Young healthy women (less than 35 years old, nonsmoking, who do not have high blood pressure) can use hormonal birth control because, for them, the risk for stroke is very low. If you are older, smoke, or have hypertension, we advise using the lowest dose of hormonal birth control. You may also choose a nonhormonal method of birth control like condoms or an intrauterine device (IUD).
Women with a history of stroke may be at higher risk for another stroke if they become pregnant. If you are a woman of childbearing age (15 to 49) and have had a stroke, use a highly reliable form of birth control and discuss any plans for pregnancy with us before trying to conceive.
There are a number of steps you can take to prevent a stroke, or a further stroke, from occurring:
Know your blood pressure
If your blood pressure is high (more than 140/90), we will work with you to help you eat better and maintain a healthy weight, take medication, stop smoking, and get more exercise.
Take statins to control your cholesterol
We treat elevated cholesterol, especially elevated LDL (known as bad cholesterol) with statin type drugs that have been shown to reduce the risk of subsequent stroke. The target LDL cholesterol for patients who have had a previous ischemic stroke or TIA is less than 100. If you have diabetes and have had a TIA or ischemic stroke, then your LDL should be less than 70.
Stopping smoking reduces the relative risk of stroke by about 30 percent immediately. Within just a few years after quitting, your stroke risk will be the same as for nonsmokers.
Use anticlotting agents
A variety of medications are commonly used to reduce the chances of blood clots forming and thus reduce the risk of ischemic stroke. These include:
- Aspirin. Among patients at high risk of ischemic stroke, those taking aspirin have a 20 to 30 percent lower risk of ischemic stroke compared to those not taking aspirin.
- Aspirin-Persantine combination treatment. This medication is also very effective in reducing ischemic strokes and may be used in some cases instead of aspirin.
- Clopidogrel. This is another alternative for patients who cannot tolerate aspirin products.
- Warfarin. This requires more monitoring and has a higher chance of complications than aspirin. However, it is better at preventing ischemic strokes in certain patients with mechanical heart valve replacements or atrial fibrillation.
If you have an emergency medical condition, call 911 or go to the nearest hospital. An emergency medical condition is any of the following: (1) a medical condition that manifests itself by acute symptoms of sufficient severity (including severe pain) such that you could reasonably expect the absence of immediate medical attention to result in serious jeopardy to your health or body functions or organs; (2) active labor when there isn't enough time for safe transfer to a Plan hospital (or designated hospital) before delivery, or if transfer poses a threat to your (or your unborn child's) health and safety, or (3) a mental disorder that manifests itself by acute symptoms of sufficient severity such that either you are an immediate danger to yourself or others, or you are not immediately able to provide for, or use, food, shelter, or clothing, due to the mental disorder.
This information is not intended to diagnose health problems or to take the place of specific medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor. If you have questions or need more information about your medication, please speak to your pharmacist. Kaiser Permanente does not endorse the medications or products mentioned. Any trade names listed are for easy identification only.