American Medical Association Family Medical Guide - American Medical Association [418]
• Control your blood pressure. Have your blood pressure checked regularly, and work with your doctor to keep your blood pressure at a healthy level.
• Take in at least 400 micrograms of folic acid every day. Consuming enough of the B vitamins folic acid and vitamins B6 and B12 (in food or in vitamin supplements) lowers your homocysteine level (see page 559), which may decrease your risk of stroke. For foods that are rich in B vitamins, see page 4.
• Keep diabetes under control. If you have diabetes, work with your doctor to control your blood sugar and avoid possible complications.
• Don’t smoke. Ask your doctor for information about how to quit smoking (see page 29).
• Take anticlotting medication according to your doctor’s instructions. If your doctor has prescribed anticlotting medication, take it exactly as prescribed, and do not take other medications without checking with your doctor first.
• Have regular checkups. See your doctor as often as he or she recommends to help detect and treat health problems in their early stages.
• Manage your stress. Find positive ways to cope with or reduce the stress in your life, such as by exercising regularly and getting enough sleep.
Transient Ischemic Attacks
A transient ischemic attack (TIA) is a significant warning sign that a person is at risk of having a stroke. In a TIA, some brain tissue does not receive sufficient oxygen because the artery that supplies that area of the brain with blood is temporarily blocked. The symptoms of a TIA are temporary, usually lasting from 2 to 15 minutes (although they can last longer, but rarely more than an hour).
A TIA usually occurs when a small blood clot or a fragment of plaque (a buildup of fatty deposits) breaks away from the wall of an artery or a heart valve and is carried through the bloodstream to the brain. As the fragment passes through blood vessels in the brain, it temporarily obstructs blood flow to an area of brain tissue and causes strokelike symptoms. Symptoms vary, depending on the area of the brain that is affected. As the clot dissolves, blood flow is gradually restored and the affected tissues recover. Although the blockage is temporary, the problem is likely to recur and the risk of permanent damage from a stroke increases.
Factors that increase the risk of a TIA are the same as those for a stroke (see page 669), including uncontrolled high blood pressure, uncontrolled diabetes, an unfavorable cholesterol profile, obesity, and lack of exercise. Recurring TIAs are often warning signs of an impending stroke. Nearly half of all people who have TIAs have a stroke within 5 years of their first TIA.
Symptoms
The symptoms of a TIA resemble those of a stroke and can include dizziness, tingling, numbness, blurred vision, confusion, difficulty speaking, and paralysis on one side of the body. If an artery that delivers blood to an eye is blocked, you may have temporary blindness in that eye. If you have sudden, temporary strokelike symptoms, see your doctor right away.
Diagnosis
To diagnose a TIA, your doctor will examine you and may refer you to a neurologist (a doctor who specializes in treating disorders of the nervous system). The doctor will try to identify the location of a possible blood clot, such as in one of the two carotid arteries in your neck. To detect signs of narrowing of the carotid arteries, a doctor may listen through a stethoscope placed in various locations on your neck. He or she may also place the stethoscope on your chest to listen for abnormal heart valve sounds or for an irregular heart rhythm (see page 580). The doctor may order an electrocardiogram (ECG; see page 559), an examination of the electrical activity of the heart. You may be asked to wear a portable ECG device called a Holter monitor for 24 hours or longer. The doctor may also order an ultrasound examination (see page 111) of your carotid arteries and heart.
If these tests indicate