Transient ischemic attacks (TIAs), sometimes called "mini-strokes," are caused by temporary reduction of blood flow to the brain. Generally, TIAs occur when platelets in the blood clump together in your arteries, blocking blood flow. Symptoms usually last only 10 to 15 minutes and clear up within 24 hours. TIAs sometimes happen before strokes, and they are considered a warning sign of stroke.

You may experience the following signs and symptoms during a TIA:

• Blurred vision in both eyes, brief blindness, or double vision
• Difficulty speaking
• Weakness, sometimes on only one side of the body
• Vertigo (a whirling or spinning feeling)
• Strange sensations, such as burning or tingling
• Trouble with coordination; clumsiness
• Loss of consciousness
• Temporary memory problems
• Headache

TIAs are commonly caused by emboli—materials that block your blood vessels. These may include clumps of platelets and fibrin (a component of blood involved in clotting), plaque (often called atherosclerosis) that has collected in your arteries, or blood clots. Some other conditions that can cause TIAs include a weakened, bulging heart wall (ventricular aneurysm); rapid, irregular heartbeat (atrial fibrillation); narrowing of the main artery in your neck (carotid artery) together with low blood pressure; and blood clotting problems.

These characteristics increase your risk for TIA:

• Over 65 years of age
• Male
• Family history of TIA
• African-American or Japanese-American
• High blood pressure
• High cholesterol
• Heart disease
• History of stroke
• Diabetes
• Smoking
• Heavy alcohol consumption
• Lack of regular physical exercise
• Hypercoagulability—an inherited condition that increases the likelihood of developing blood clots, including during pregnancy

If you have symptoms of TIA, see your healthcare provider. Your provider will ask about your symptoms, examine you, and may perform tests, such as blood tests, computed tomography (CT) scan or magnetic resonance imaging (MRI) of your head, or ultrasound of the blood vessels to your brain. If the ultrasound shows some blockage, your provider may consider a test called an angiogram to view the blood vessels more clearly. These tests will help your provider determine whether you had a TIA or another event and what the cause may have been.

You can take the following steps to help prevent TIA:

• Don't smoke.
• Get regular exercise, eat a healthy diet, and maintain a healthy weight.
• Don't drink alcohol excessively.
• Work with your provider to control high blood pressure, high cholesterol, or diabetes.
• Work with your provider to treat carotid artery disease, coronary artery disease, irregular heartbeat, congestive heart failure, or heart valve disease.
• Stay on hormone replacement therapy if you are already taking it.

Treatment will depend on your signs and symptoms, exam, and tests. Your provider may admit you to the hospital to evaluate your condition more thoroughly and to treat you if your condition becomes worse. You may need oxygen to help you breathe and to lessen the effects of blocked blood flow.

To help prevent TIA, stroke, or heart attack, your provider may prescribe antiplatelet agents (drugs that prevent platelets from clumping), or anticoagulants (drugs that prevent blood from clotting). These include aspirin, ticlopidine, clopidogrel, dipyridamole, and warfarin.

If your carotid artery is narrowed, your provider may recommend a type of surgery called carotid endarterectomy to clean deposits from inside the artery. While examining your carotid artery, your provider may perform angioplasty (inserting a balloon, a tube-like structure called a stent, or another device into your artery to open it). Depending on your condition, your provider may recommend an extracranial-intracranial bypass, surgery that connects a blood vessel outside your skull with a blood vessel inside to improve blood flow.

Diet is very important in preventing and treating blood vessel (vascular) diseases. Some nutrients and herbs may protect against injury from reduced blood flow and damage from oxidation (a process that occurs in the body with age and in response to exposure to certain agents such as cigarette smoke and fatty foods). Acupuncture plays a role in the circulation of blood in your head and in reducing adverse effects when blood flow returns.

An important, long-term study called the Framingham Study showed that among men aged 45 to 65 years with no known history of vascular disease, those who ate more fruits and vegetables had a lower risk of stroke and TIAs. A study of 14,916 men aged 40 to 84 years examined whether homocysteine levels would be a good predictor of stroke risk. The study showed homocysteine levels were slightly, but not significantly, higher in men who later had strokes. Homocysteine levels were a better predictor of stroke in men who had normal blood pressure or were 60 years old or younger. Folic acid (vitamin B₉), vitamin B₆, vitamin B₁₂, and betaine affect your body's use of homocysteine. Taking these supplements may help control homocysteine levels.

A review of the role of magnesium in vascular disease shows a link between the dietary intake of magnesium, the amount of magnesium in the heart and blood vessels, and the risk for developing TIAs and other blood vessel problems. This suggests that taking magnesium through dietary sources (such as green leafy vegetables, whole grains, nuts and seeds, tofu, oatmeal, bananas, potatoes, and molasses) may be useful; not enough information is available to determine if magnesium supplements are worthwhile.

A study of 10 patients who suffered a stroke related to reduced blood flow showed that the supplement acetyl-L-carnitine improved blood flow around, but not directly in, the affected site in the brain. In an animal study, treatment with acetyl-L-carnitine before reducing blood flow protected nerve cells. This supplement may help prevent TIAs for high-risk patients and/or may prevent further brain damage for those who have already suffered a TIA or an ischemic stroke.

Vitamin E helps prevent platelets from sticking together, which improves blood flow. In a 2-year study, 100 patients with a history of cerebrovascular events were randomly assigned to take either aspirin or a combination of aspirin and vitamin E. Those taking the combination had fewer platelets collecting in blood vessels and improved blood flow. Several animal studies have also shown that vitamin E protects against the effects of reduced blood flow.

Vitamin B₃ is under investigation as a possible treatment for TIAs in humans. In animal studies, rats were treated with vitamin B₃ following a TIA. Results showed the treatment protected the nerve cells and reduced damage from the TIA. More research is necessary to determine if the same is true for people.

Ginkgo (Ginkgo biloba) appears to increase circulation in the head, helps the brain tissue tolerate lack of oxygen, controls brain swelling, improves brain function, protects nerve cells, and lessens the likelihood of platelets collecting in blood vessels. In animal studies, treatment with ginkgo before intentionally causing a TIA helped preserve the brain membrane.

Oren-gedoku-to (TJ15), a Chinese herbal preparation, reduced nerve cell damage in mice with reduced blood flow to the brain. Specialists trained in Chinese medicine and licensed to prescribe Chinese remedies would decide whether this herb or others might be useful for you if you have a history of TIA or stroke.

Scientific literature does not support the use of homeopathy for TIAs. An experienced homeopath would consider your individual case and may recommend treatments to address both your underlying condition and any current symptoms.

In an animal study of reduced blood flow to an area of the head, scalp acupuncture improved neurologic symptoms and blood flow, helped repair damage, and reduced swelling, inflammation, and tissue death. In a study of patients with cerebrovascular disease, electrical stimulation of the needles during acupuncture (called electro-acupuncture) caused improvement in blood flow to the brain compared to acupuncture alone. Animal studies have confirmed the benefits of electro-acupuncture in protecting overall function in the brain when blood flow is reduced and in improving recovery when blood flow returns.

Pointed massage on acupuncture points (called acupressure) improved blood flow in the head in 120 patients with brain disorders due to poor circulation and a history of TIAs in the vessels supplying blood to the back of the head.

Chiropractors do not treat TIAs, and high velocity manipulation of the upper spine is considered inappropriate in individuals who are taking blood-thinning medications or other medications used to reduce the risk of stroke. It should also be noted that chiropractic spinal manipulation of the neck is associated with an exceedingly small risk of stroke (0.5 strokes reported per 2 million spinal manipulations).

The shorter the amount of time between TIAs, the more likely it is that you will have a stroke; this seems to be the most important predictor of stroke risk. Narrowing of the carotid arteries also indicates likelihood of suffering a stroke. The location or duration of symptoms do not appear to be indications of stroke risk.

TIAs are a warning sign of stroke. But more patients with TIA die from heart attack than stroke. If you have a stroke and are not treated right away, you may be more likely to have complications, such as pneumonia, hypothermia, dehydration, or serious skeletal muscle problems. Damage to the brain stem may lead to breathing problems. Bleeding or swelling in the head may occur days after a stroke. Multiple strokes increase the risk of seizure, blood clots to the legs or lungs, and impaired memory or judgment (dementia).

Follow your provider's advice on getting checkups after a TIA to prevent stroke and heart attack. In people who have strokes after TIAs, half the strokes occur within a year, and 20% occur within 5 months.

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