A transient ischemic attack (TIA), sometimes called a little stroke or mini-stroke, is a brief interruption of blood flow to the brain. It is distinguishable from an actual stroke, or ischemia, because it is temporary, and all symptoms are gone within 24 hours. Although its varied names might seem to imply that a TIA is not serious, that is not the case. Over one third of people who have an ischemic attack suffer a stroke shortly afterward. Therefore, TIA requires immediate medical attention.
Interruption of blood flow to different areas of the brain causes those areas to shut down, if only temporarily. Within a few minutes, though, brain cells with no blood supply can die and permanent brain damage can occur. If a significant number of brain cells are damaged, then the interruption of blood flow is a stroke. If only a few cells are damaged and symptoms dissipate in less than 24 hours, then diagnosis is transient ischemic attack.
People experiencing an ischemic attack may have one or several symptoms. TIA can cause numbness, confusion, speech difficulty, loss of balance, vision changes, changes in gait, changes in balance or coordination, and facial paralysis. These symptoms occur quite suddenly and last for a relatively short time period, under 24 hours.
An ischemic attack can be caused by narrowing of major arteries, blood clots forming in or traveling to the brain, cancer, and inflamed or injured blood vessels. The following factors can predict a higher degree of susceptibility to both TIA and ischemia:
- Smoking
- Low blood pressure
- Heart disease
- Diabetes
- Increasing age
Less commonly, those who have congenital heart anomalies, sickle cell anemia, syphilis, or systemic lupus have an increased risk of TIA.
Diagnosis of transient ischemic attack is made through a number of different means. The physician will generally take a complete medical history and ask questions about the symptoms to determine which areas of the brain have been affected. The patient's blood pressure will be taken and the doctor will listen to the heart to determine whether evidence of hardened or blocked arteries can be heard.
Further tests will be done both to confirm the diagnosis of TIA and to help identify its causes. Blood tests will evaluate the clotting-time of blood, known as PT or pro-time; and a complete blood count (CBC) will look at the thickness, size and number of red and white blood cells. Other blood tests may rule out or confirm underlying causes of ischemic attacks such as diabetes or sickle cell anemia. Chest X-rays, ultrasounds, and magnetic resonance imaging (MRI) may additionally be used.
Treatment varies, but its primary goal is to prevent stroke and further incidences of ischemic attack. If the TIA is caused by a specific condition, treatment will focus on allaying that condition. In general, those suffering from TIA are likely to be given anti-coagulants like aspirin or warfarin to prevent excessive blood clotting. Patients will be strongly advised to quit smoking if they smoke. Diets specific to the needs of diabetics or to those with high blood pressure may be recommended. When an ischemic attack has occurred in a patient with carotid artery obstruction, surgery can be performed to clear the artery.
Transient ischemic attacks are not in themselves life-threatening, but they can be frightening. They are, in a sense, the body's way of communicating that the person afflicted has underlying conditions that may be life threatening without treatment. Therefore, anyone suffering a TIA needs to seek medical attention immediately to diagnose these conditions and treat them prior to suffering the more debilitating effects of a stroke.
