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Stroke
Despite the fact that more than 730,000 Americans experience a stroke each year, most people do not know very much about the disease. In fact, according to the National Stroke Association, 38 percent of us don't know where in the body a stroke occurs, and 42 percent can't identify its most common symptoms.
A stroke (also known as a 'brain attack') occurs when the blood flow to an area of the brain is interrupted by a blocked (or broken) blood vessel and brai cells in the immediate area are destroyed. When this happens, the dying cells release chemicals that set off a chain reaction. This endangers the brain cell surrounding the area of injury. Prompt medical treatment can minimize the damage to this area.
Facts About Strokes:
 Stroke is not a 'seniors' disease. In fact, about one-third of all strokes happen to people under 65.
Stroke is the third-leading cause of death in the United States.
Approximately 20 percent of stroke survivors will have another stroke within a year.
Several United States presidents suffered strokes, including: Jefferson, Wilson, Harding, Roosevelt, Eisenhower and Nixon.
'The stroke belt,' where most strokes occur, is located in the eastern/midwestern section of the country, and from the mid-Atlantic southward. These are the states with the highest percentage of stroke cases. According to the National Stroke Association, this may be attributed to a number of factors, including:
A higher-than-average population of African-Americans
A higher-than-average population of older adults
Dietary factors
Types of Stroke
'Brain attacks' occur in two ways:
Ischemic Stroke
Ischemic stroke is caused by a blockage in a blood vessel in the brain. This blockage may stem from several sources, including clots from the heart or legs, plaque from the valves of the heart or other blood vessels. If a clot or plaque breaks free and travels to the brain, stroke occurs. Approximately 8 percent of all strokes are ischemic. All patients who experience strok symptoms should call 911 immediately.
Transient Ischemic Attack (TIA)
A TIA is sometimes called a 'mini-stroke.' It is usually due to a blockage caused by platelets clumping together. After a short period of time, thes clumps break up, allowing the blood flow to resume. Most symptoms of a TI resolve in 24 hours. Having experienced a TIA increases the chance that atient will experience a full-blown stroke. All patients who experience strok symptoms should call 911 immediately. It is important to determine the cause of the symptoms and thereby reduce the risk of stroke.
Hemorrhagic Stroke
In hemorrhagic strokes, a blood vessel in the brain leaks or ruptures. Hemorrhagic stroke can be caused by a number of disorders which affect th blood vessels, including arteriorscleresis and long-standing high blood pressure. A ruptured aneurysm may be considered another type of hemorrhagic stroke. Within Sentara, there is a dedicated team of neurosurgeons and neuroradiologists to treat aneurysms and other neurovascular disorders. All patients who experience stroke symptoms should call 911 immediately.
Symptoms
Stroke is a medical emergency. Know these warning signs of stroke and teach them to others. Every second counts (Time lost is brain lost!):
Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
Sudden confusion, trouble speaking or understanding
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden, severe headache with no known cause
The most important thing to remember is that stroke is an emergency - call 9-1-1 immediately if you experience symptoms. It is literally a 'brain attack' and it is just as serious as a heart attack. Seeking medical attention could save your life, and is critical in saving brain function.
Remember: TIME = BRAIN!
Over the past few years, revolutionary new drugs have been developed that can effectively treat acute ischemic stroke. But, again, they must be administered within three hours after the onset of stroke symptoms. Do not delay.
Effects of Stroke
Patients and their families are understandably very concerned about what specific abilities will be lost or affected by stroke. This is difficult to assess, because the brain is an incredibly complex organ, and each area has responsibility for a particular function or ability. The nature and extent of how a patient is affected depends upon the extent of injury and where the stroke occurred.
Strokes that occur in the right side of the brain affect movement of the left side of the body, and can interfere with analytical and perceptual tasks.
Strokes that occur in the left side of the brain can affect the movement of the right side of the body, and can influence speech and language abilities.
Strokes that occur in the cerebellum can cause abnormal reflexes of the head and torso, coordination problems, dizziness, nausea and vomiting.
Strokes that occur in the brain stem can affect life-support functions, such as breathing rate, blood pressure and heartbeat, as well as other functions such as vision, swallowing and articulation. Testing There are several tests that can be conducted to ascertain whether you have had a stroke, and to determine the extent of the damage.
Peripheral vascular studies, also known as 'doppler ultrasound': This non- invasive procedure can detect blockages that may be present in the carotid arteries by detecting an increased velocity of red blood cells over narrowed sites. A microphone-like device is placed on the neck arteries, affixed with a gel. You will be asked to keep your neck turned away from the artery being tested. The test measures the blood flow through the artery to determine the amount of stenosis (blockage), plaque or irregularities in the artery. It takes approximately 30-45 minutes.
Echocardiogram: This non-invasive test, conducted on your heart, transmits pulses of sound into the body, then electronically plots and records the echoes returning from the surfaces of the heart. It measures the function an strength of the heart muscles and valves to detect whether or not a blood clo in the heart or on the heart valves is the source of the stroke.
TEE (Transesophageal Echocardiogram): This is an invasive procedure in which a tube containing a special sensor device is inserted into the esophagus (through the mouth) to evaluate the function of the heart and fin the source of the blood clot.
Coagulation studies: These involve drawing and analyzing the blood to determine your body's ability to coagulate (or clot).
CT (Computed Tomography) scan: This is a combination of an X-ray device and a computer. X-rays are taken of the brain, and this information is fed into a computer which transforms the data into a picture. In some cases, the patient is injected with a special dye to make abnormal tissue more evident. CT scanning is usually the first test conducted in evaluating stroke.
MRI (Magnetic Resonance Imaging): This procedure uses a tunnel-shaped piece of equipment that contains a magnetic field and radio energy; no x-rays are involved. Magnetic signals are fed into a computer which assembles a picture. Because the MRI ignores bone which can obstruct CT images, this device provides a clearer picture of tumors located near the bone, and can provide a wider variety of image angles. It can detect edema (swelling), but has difficulty distinguishing edema from a tumor, and will not be able to detect the specific type of tumor. MRI imaging takes longer than a CT scan, and is very noisy. Patients with cardiac monitors, pacemakers or surgical clips cannot take an MRI because of conflict with the magnetic fields. MRI scanning is very helpful in detecting stroke and displaying the extent of brain damage that has occurred.
Angiography: This is a procedure in which a contrast dye is injected into the blood vessels that supply the brain. An angiogram is the best way to detect an aneurysm or other vascular malformation.
Treatment
Non-surgical
There are a number of medical/therapeutic treatments for stroke. Remember that it is critical to seek medical assistance as soon as you begin to experience any stroke symptoms.
t-PA (tissue plasminogen activator) for the treatment of acute ischemic stroke. For many patients, t-PA (administered intravenously within three hours of symptoms) can significantly aid in recovery and improve outcomes. It is considered a 'clot-busting' drug.
Use of aspirin and other antiplatelet medications (as prescribed by your doctor) to reduce the risk of future strokes.
Use of neuro-protective agents (currently being assessed in clinical drug trials). These are designed to protect the brain from delayed injury during the course of ischemic stroke, and, like t-PA, must be administered shortly following onset in order to be effective.
Interventional radiology (which is still in an investigational stage for treatment of ischemic stroke) can be used to supplement therapy in the case of acute stroke. These therapies include:
1) The use of radiology-guided microcatheters which administer clot dissolving medication directly to the area of circulatory occlusion;
2) The use of radiology-guided balloon catheters (similar to those used for cardiac catheterization) that can be guided to the area(s) of vascular narrowing, followed by balloon dilatation (angioplasty) to widen the narrowed segment of the artery;
3) A certain number of strokes are caused by leaking aneurysms (areas of weakness in the blood vessel wall). Leaking aneurysms are detected by catheter angiography, and can be treated with catheter techniques that deliver soft platinum coils (GDC) to the aneurysm to seal it.
Surgical
Surgery may be used to treat selected hemorrhagic strokes by removing large blood clots and thereby decreasing intracranial pressure on the surrounding brain tissue. There are several surgical procedures that can relieve pressure. The most effective way to treat a ruptured aneurysm is a procedure in which a neurosurgeon places a small clip across the aneurysm to close it. Other procedures that can relieve pressure are performed as well.
Research
There are several promising new neuroprotective agents (drugs) that are currently in the developmental/testing phase designed to protect the brain following a stroke and to reduce the damage caused by stroke in the U.S.
Prevention
Some factors that place a person at risk for stroke can be controlled, others cannot. Having an uncontrollable risk factor does not necessarily mean that a person will have a stroke, but it makes it all the more important to do what you can to control your risk through healthy lifestyle management.
Uncontrollable Risk Factors:
Age, gender, race, family history of stroke and personal history of diabetes are all risk factors over which we have no control.
Specifically:
Two-thirds of all strokes happen to people over 65.
African-Americans have almost double the stroke risk of most other racial groups.
Risk is higher for people with a family history of stroke.
People with diabetes have a higher stroke risk, even though elevated blood sugars can be controlled.
Controllable Stroke Risk Factors:
Conducting a healthy lifestyle is the best 'insurance policy' for preventing stroke. It is even more important for people who have had a stroke or transient ischemic attack (brief episode of stroke symptoms), because they are more likely to be at risk for having another.
High Blood Pressure
Having high blood pressure increases the risk of stroke four to six times. It is the single-most important controllable stroke risk factor. Blood pressure is considered high when it is consistently more than 140/90.
High blood pressure puts stress on blood vessel walls and can lead to strokes from blood clots or hemorrhage. Because there are rarely any outward symptoms of high blood pressure, it's important to have your blood pressure checked at least every two years (more often if there is a history of high blood pressure). If you have high blood pressure, your doctor may ask you to:
Limit salt in your diet
Lose weight
Stop smoking, and
Exercise regularly.
When blood pressure can't be controlled through lifestyle modification, your doctor may prescribe an antihypertensive medication. It is important to take the medication exactly as directed; skipping doses or letting your prescription run out can increase your risk for stroke.
Atrial Fibrillation and other Heart Diseases
Having heart disease increases stroke risk up to six times. Heart disease is linked to the buildup of fatty deposits in blood vessel walls. About 15 percent of all people who have a stroke have a heart dysarrhythmia called atrial fibrillation, or AF. AF causes the chambers of the heart to beat rapidly and irregularly. This causes the heart to beat inefficiently, leaving blood in the chamber. When blood pools, it can form clots which could be carried to the brain. Your doctor may choose to treat your dysarrhythmia by prescribing medication and asking you to change your diet, exercise and/or stop smoking.
High Cholesterol
High cholesterol can increase stroke risk. Increased levels of cholesterol cause plaque to form in the arteries, decreasing the flow of blood. Your doctor may choose to treat your high cholesterol by prescribing a low-fat diet and exercise. If cholesterol levels remain high after lifestyle modification, medication may be required.
Smoking
Smoking doubles the risk of stroke. It damages blood vessel walls, speeds up clogging of the arteries, raises blood pressure and makes the heart work harder. If you need help to quit smoking, ask your doctor for suggestions.
Alcohol
Excessive consumption of alcohol is associated with stroke in a number of research studies. Its specific role in stroke has not yet been determined or proved. Check with your physician.
Weight
Excess weight puts a strain on the entire circulatory system. It also makes you more likely to have other stroke risk factors such as high cholesterol and high blood pressure. If you are overweight, you should talk with your doctor about setting reasonable weight loss and exercise goals.
Support Groups/Resources
Many patients and families find great comfort and support in talking with other patients, families and caregivers who have had (or are having) similar experiences. Support group meetings are free of charge, and are facilitated by a trained peer or qualified professional. The following numbers should help you get more information and/or find a group nearest you:
The National Stroke Association
Phone: 1-800-STROKES
American Stroke Foundation
Phone: 1-866-549-1776
The National Institute of Neurological Disorders and Stroke
Phone: (301) 496-5751
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