Definition

Transient ischemic attack (TIA) is a temporary dysfunction of the brain due to a shortage of blood and oxygen. A TIA lasts no longer than 24 hours. It is sometimes referred to as a mini-stroke.

TIA is a serious condition. It serves as a warning for a potential stroke.

Causes

Blood and oxygen are carried to the brain through major blood vessels in the neck. The blood then passes through a series of blood vessels in the brain. A TIA occurs when the blood flow through the neck or brain vessels is reduced. The blood flow may be reduced by a narrowing or blockage of the blood vessels.

Narrowing of the blood vessels may occur with:

• Build up of plaque in the blood vessels, called atherosclerosis
• Vasculitis—inflammation of the blood vessels

Blood vessels can also become blocked or obstructed by a clot or clump that is floating in the blood. This may be caused by:

• A piece of blood clot or plaque that has broken off of another location
• Blood and blood-clotting disorders such as:
  • Severe anemia —too few red blood cells
  • Polycythemia —too many red blood cells
  • Hyperviscosity—abnormal thickening of the blood
• Endocarditis —an infection of the lining of the heart

Risk Factors

Certain chronic medical conditions can affect the health of your blood vessels. These conditions may increase your chances of TIA:

• Diabetes
• Obesity
• Metabolic syndrome
• Heart disease

TIAs are more common in men than women in younger age groups. They are also more common in people age 45 years or older, with the highest risk between ages 60-80 years. Other factors that increase your chance for TIA include:

• History of previous TIAs
• Smoking
• Poor diet
• Sedentary lifestyle
• Alcohol use disorder
• Sleep apnea
• Low bone mineral density, especially in women
• Vascular dementia

Symptoms

TIA symptoms occur abruptly. They usually last less than an hour, but they may persist for up to 24 hours. The symptoms are different depending on the part of the brain that is affected. TIA symptoms are similar to those of a stroke and need immediate medical attention.

Symptoms may include:

• Blindness in one eye, often described as a window shade dropping, and/or other visual problems
• Weakness, numbness, or tingling of the face, arm, leg, or one side of the body (usually affects one side of the body, but there are exceptions)
• Difficulty speaking or understanding words
• Lightheadedness, unsteadiness of gait, or falling
• Trouble with balance or coordination
• Loss of consciousness
• Nausea
• Vomiting
• Sudden confusion or loss of memory

Diagnosis

The doctor will ask about your symptoms and medical history. A physical exam will be done. Your doctor will carefully assess your blood pressure and nervous system. The main goal of tests or questions will be to determine your stroke risk.

Tests may include:

• Blood tests
• Electrocardiogram (EKG)—to measure your heart’s electrical activity
• Doppler ultrasound —to assess blood flow in the arteries supplying the brain
• Echocardiogram —to look for blood clots and valve abnormalities within the heart
• CT scan of the head
• CT angiogram—to assess blood vessels in the brain and neck with contrast dye
• MRI of the head
• MR angiography—to assess blood vessels in the head using magnetic imaging
• Arteriogram—to locate and assess blockage or narrowing of blood vessels using contrast dye

Treatment

A TIA places you at greater risk for having a stroke. The risk is actually highest in the first week after your TIA. Therefore, rapid treatment aims to decrease your risk of stroke. This can be done with lifestyle changes, medication, and surgery.

Prevention

To reduce your chance of TIA or stroke, take these steps:

• Exercise regularly, with your doctor’s approval.
• Eat a healthy, balanced diet. It should be low in saturated fat and rich in whole grains, fruits, and vegetables.
• Maintain a healthy weight.
• If you smoke, find out ways you can successfully quit.
• Drink alcohol in moderation. Moderate alcohol intake is no more than two drinks per day for men and one drink per day for women.
• Control blood pressure, high cholesterol, and diabetes if you have these conditions.

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