What is TIA?
A transient ischemic attack (TIA) occurs when blood flow to part of the brain is interrupted by a temporary blockage in an artery supplying the brain. The pathological mechanism of a TIA is identical to that of certain kinds of stroke, except that normal circulation is restored within 24 hours and no permanent brain damage occurs. Most TIAs resolve within a few minutes to an hour. Symptoms appear suddenly and vary considerably depending on the part of the brain affected. Although TIA symptoms disappear completely without treatment, they often recur. Prompt medical attention is important: TIAs are a warning sign of an impending stroke.
What Causes Transient Ischemic Attack?
- The majority of TIAs are associated with atherosclerosis, a buildup of plaques in the walls of the arteries. A TIA may develop when a plaque becomes substantial enough to reduce blood supply locally in an artery supplying the brain. More commonly, however, a TIA occurs when a small fragment of a plaque that has broken off from a blood vessel, or a blood clot (embolus), usually from the heart, travels to an artery supplying the brain and lodges in a site already narrowed by atherosclerosis.
- Major risk factors for TIAs include high blood pressure, heart disease, diabetes, smoking and aging.
Symptoms of Transient Ischemic Attack
- Sudden weakness, tingling, or numbness, usually affecting only one side of the body
- Changes in sensation, such as pressure, touch, hearing, temperature, pain and taste
- Double vision or temporary blindness in one eye
- Loosing control over the bladder or bowels
- Speech difficulty
- Personality or mood swings
- Dizziness and loss of balance or coordination
- Swallowing difficulty
- Lightheadedness, confusion or amnesia
- Reading or writing difficulty
- Headache or eye pain
- Inability to recognize sensory stimuli (agnosia)
- Seek treatment for any predisposing condition, such as hypertension, diabetes or heart disease.
- Don’t smoke.
- Lose weight if you are overweight.
- Patient history and physical examination are needed to rule out other disorders such as epileptic seizures and migraines.
- Blood tests are taken to rule out disorders like hypoglycemia.
- Imaging studies may be done, such as MRI (magnetic resonance imaging) of the brain or ultrasound scans of the carotid arteries.
- An echocardiogram can be performed to check if there’s a blood clot from the heart.
- Cerebral arteriography (injection of a contrast material into the blood vessels supplying the brain to highlight them during x-ray imaging) may be performed in some cases.
- Carotid duplex (ultrasound) can be used check if the carotid arteries in the neck have narrowed.
How to Treat TIA
- Drugs that inhibit blood clot formation may be prescribed. Aspirin—the most commonly used antiplatelet agent—is usually tried first. More powerful anticoagulants such as warfarin and heparin may be warranted in some cases.
- Blood thinners drugs such as dipyridamole, Aggrenox, clopidogrel, heparin and coumadin can be prescribed.
- Measures to control hypertension and blood cholesterol levels (including drug therapy) are undertaken if needed.
- Patients who have experienced one or more TIAs, who are healthy enough to have surgery and who show evidence of substantial atherosclerotic narrowing in the carotid arteries (the two main blood vessels in the neck supplying the brain) may be good candidates for carotid endarterectomy—a surgical procedure to clear away plaque deposits in the arteries. This technique is not appropriate for all patients, but in those who do qualify, it has been shown to reduce the risk of having a stroke in the future.
When to Call a Doctor
- If you experience the symptoms of a TIA, visit a doctor immediately. Do not ignore symptoms just because they go away by themselves.
Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference
Simeon Margolis, M.D., Ph.D., Medical Editor
Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50
Updated by Remedy Health Media