Stroke, Brain Infarct or Cerebrovascular Infraction
Stroke, sometimes called a brain attack, is a general name for a variety of disorders that occur within seconds or minutes when the blood supply to the brain is interrupted. Approximately 700,000 Americans suffer strokes every year. Stroke is the third leading cause of death in the United States, killing approximately 163,000 people each year.
There are four major types of strokes - two are caused by clots, and two by hemorrhage. The two caused by clots, cerebral thrombosis and cerebral embolism, account for 70 to 80 percent of all strokes. The remaining two, cerebral and subarachnoid hemorrhages, are caused by ruptured blood vessels and have a much higher fatality rate than strokes caused by clots.
Cerebral thrombosis: Cerebral thrombosis, the most common kind of stroke, occurs when a blood clot forms in an artery, blocking the flow of blood to the brain. A TIA often proceed these types of strokes.
Cerebral embolism: This type of stroke occurs when a blood clot forms in a distant body part, often the heart, and is carried to one of the major arteries in the brain, where it blocks blood flow. A heart disorder called atrial fibrillation is a risk factor for this kind of stroke.
Subarachnoid hemorrhage: This type of stroke is caused when a blood vessel on the surface of the brain ruptures, bleeding into the space between the brain and the skull.
Cerebral hemorrhage: About 10 percent of strokes are cerebral hemorrhages, which occur when an artery in the brain bursts because of a head injury or an aneurysm. An aneurysm is a weak blood vessel that swells out like a balloon - though they're not always dangerous, the artery wall can weaken and burst.
Damage can result from cerebral hemorrhages in two ways - loss of blood supply to the brain and pressure from the accumulated blood. Although this type of stroke has a fairly high fatality rate, those who survive have an especially good chance of full recovery.
1. Sudden weakness, paralysis or numbness of the face, arm or leg, especially on one side of the body.
2. Sudden onset of double vision, dimness or loss of vision.
3. Sudden difficulty speaking or understanding language.
4. Sudden severe headache without apparent cause.
5. Unexplained dizziness, unsteadiness or loss of balance, especially in combination with other signs.
Sometimes, people will experience brain infarct
symptoms that disappear within a few minutes. These "mini-strokes" - transient ischemic attacks (TIAs) - are caused by temporary interruptions to the blood supply of the brain. TIAs are a risk factor for stroke and shouldn't be ignored. About one-third of people who have a TIA will eventually have a stroke, one-third will continue to experience occasional TIAs, and the final third won't have further symptoms. Your doctor will perform tests to determine the cause of TIAs and treat the problem through surgery or medication, if possible.
Anyone, no matter what age, race or sex, can experience a brain infarct
. However, stroke is much more likely to occur with age. After age 35, your risk of having a stroke doubles every 10 years. Five percent of the population older than 65 has had some form of stroke.
The death rate from brain infarct
among African-Americans is almost twice that of white Americans. There is no clear explanation for this, but researchers are evaluating risk factors in minority groups to discover why. You can reduce your risk of stroke by doing the following.
Control high blood pressure. It is estimated that 70 percent of all strokes occur in people with high blood pressure. Ways to decrease your blood pressure include cutting back on salt, exercising regularly and losing weight. Your doctor may prescribe medications to reduce blood pressure — if so, it is important to take them as directed.
Stop smoking. Reduced brain infarct
risk is among the many health benefits of quitting smoking. Cigarette smoking has been linked to the build-up of fatty substances in the carotid artery, which supplies blood to the brain blockage of this artery is the leading cause of stroke among Americans. Plus, substances in cigarette smoke such as nicotine and carbon monoxide increase blood pressure, make blood more likely to clot and reduce the amount of oxygen the blood can carry to the brain.
Control diabetes. Diabetes is a disorder affecting the body's ability to process sugar. It also can cause blood vessel damage throughout the body, including the brain, and if blood sugar levels are high at the time of a stroke, then brain damage often is more severe. Keeping diabetes under control can help delay or prevent complications that increase stroke risk.
Treat heart disease. Many common heart disorders, including valvular heart disease, recent heart attack, irregular heartbeat and atherosclerosis, can contribute to your stroke risk. Your doctor will treat the heart disease and may prescribe medicine, often aspirin, to help prevent blood clot formation.
Seek immediate treatment for transient ischemic attacks. Transient ischemic attacks (TIAs) are caused by temporary interruptions to the blood supply of the brain. TIA symptoms are similar to stroke symptoms, but last only a few minutes before disappearing completely. TIAs are a risk factor for stroke, so they should not be ignored.
Some patients may be treated with medication alone. Others may undergo a type of test called cerebral arteriography, which maps the blood supply to the brain so that doctors can see where the blockage is occurring. The test can provide important information on whether to treat TIAs or stroke with surgery to remove the blockage. One type of surgery for TIAs is called carotid endarterectomy in which doctors remove plaque from the carotid artery to improve blood supply to the brain.
Acute care for people who have just suffered a brain infarct
often includes life-support equipment to supply oxygen, nutrients and medications. Unfortunately, there is no way to “cure” brain damage caused by a stroke. The main goal of acute care is to help the patient survive by preventing another stroke and taking care of any other medical problems. The doctor may prescribe drugs (anticoagulants) that decrease the blood's clotting ability.
Most patients begin to spontaneously recover from their strokes, slowly regaining lost abilities. This process usually is fastest during the first few weeks, but patients may continue to improve for a long time.
The prognosis for every brain infarct
patient is different, depending on where in the brain the stroke occurs, how much damage is sustained and the patient's overall health. Some patients will make a complete or nearly complete recovery. Others are disabled through the loss or partial loss of speaking ability or memory, while others suffer permanent paralysis or weakness.
After a brain infarct
, rehabilitation is vital to help the patient recover as quickly and completely as possible. Many decisions about which kind of rehabilitation program is necessary are made by the physician, family and patient before the patient is released from acute care. Rehabilitation programs and services commonly include physical, occupational and recreational therapy customized to each individual patient.
Treatments for stroke vary depending on the type of stroke, health of the patient and rehabilitation needs, etc.
Drug therapy is a relatively recent approach to the treatment of stroke, and a tremendous amount of research is under way to find effective new drugs that can minimize damage.
Much of the damage caused by a thrombotic or embolic stroke occurs in the first six hours. The primary areas of research have focused on the development of new clot-dissolving drugs and medications that make the brain more resistant to stroke (neuroprotective agents).
Drugs that dissolve clots are known as thrombolytic agents. Experimental data and pilot clinical studies suggest that if given within the first few hours after stroke onset, these drugs may dramatically minimize stroke damage.
Thrombolytic Agents (tissue plasminogen activator [tPA]), widely used to dissolve clots that cause heart attacks, are also effective for dissolving artery-blocking clots in the brain during the critical early stages of stroke. Early administration of tPA after a stroke can reduce neurological damage significantly.
Neuroprotective Agents - Medications that make the brain less susceptible to the damaging effects of a stroke are called neuroprotective agents.
Stroke Prevention: A number of medications that help prevent stroke in high-risk patients, particularly those who have had a previous TIA or minor stroke. These drugs fall into two major categories: anticoagulants (such as Warfarin or ximelagatran) and antiplatelet agents (such as aspirin, dipyridamole and clopidogrel).
Anticoagulants may be given orally or intravenously. These drugs work by thinning the blood and preventing clotting. They are also used for treatment and prevention of deep vein thromboses and pulmonary emboli.
Antiplatelet Agents work by preventing or reducing the occurrence in the blood-stream of a phenomenon known as platelet aggregation. When there is damage or injury to a blood vessel, platelets (one type of blood particle) migrate to the scene to initiate a healing process. Large numbers of platelets clump together (aggregation) and form what is essentially a plug. This aggregation can sometimes result in formation of a thrombus (blood clot) that may totally block the artery or break loose and block a smaller artery. By preventing this from occurring, antiplatelet agents can reduce the risk of stroke in patients who have had TIAs or prior ischemic strokes.
Overall, the most common risk factors for stroke are:
1. High blood pressure,
2. High cholesterol.
5. Increasing age.
Heart rhythm disturbances like atrial fibrillation, patent foramen ovale, and heart valve disease can also be the cause.
When brain infarct
occur in younger individuals (less than 50 years old), less common risk factors are considered including illicit drugs, such as cocaine or amphetamines, ruptured aneurysms, and inherited (genetic) predispositions to blood clotting.
An example of a genetic predisposition to it occurs in a rare condition called homocystinuria, in which there are excessive levels of the chemical homocystine in the body. Scientists are trying to determine whether the non-hereditary occurrence of high levels of homocystine at any age can predispose to brain infarct
The best way to diagnosis stroke:
A computed tomography, or a CT scan, is the best way to determine if a stroke was caused by a ruptured artery. A CT scan also can show the location and size of a damaged area.
Magnetic resonance imaging (MRI) is similar to a CT scan, but instead of using X-rays, it uses a magnetic field to create a signal that a computer can translate into a message. MRIs can diagnose strokes caused by blockages or ruptures.
Carotid ultrasound uses sound waves to find the location and extent of blockages in the carotid arteries in your neck. These arteries supply blood to your brain, so a clot in one of them can cause a stroke.
Cerebral angiography: If an ultrasound finds a blocked carotid artery, cerebral angiography is used to get more information. This procedure produces an image of the arteries in your brain and your neck so your doctor knows the location and extent of blockages in these areas. Doctors can also diagnose blood vessel abnormalities.
Carotid endarterectomy: Removes plaque from the artery.
Medicine and medications:
Aggrenox®, Persantine®, others
6. Tissue Plasminogen Activator
Acute stroke treatment.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.