Often referred to as the “mini” stroke or a “warning” stroke, a TIA or a transient ischemic attack is a physiological episode that is characterized by a specific area or multiple areas of the brain being subjected to changes (decrease) in the supply of blood and therefore also oxygen. TIA (transient ischemic attack) or the “mini” stroke differs from other similar episodes in that its neurologic dysfunctions are brief (lasting less than 24 hours but most last only 5 minutes) while the reversible ischemic neurologic deficit or RIND lasts between 24 and 72 hours and a full-size major stroke (CVA) persists for much longer and leaves permanent damage of any kind.
TIA does not always precede a major stroke but statistics show that approximately 35% of those who have suffered a TIA will also have a major stroke at some later date, usually within one year. However, accurate diagnosis, effective treatment of TIA and preventive measures can somewhat reduce the risk of a major stroke.
Symptoms and Warning Signs
Depending on which area or areas of the brain are involved and on the victim’s age, gender, overall health, and a whole lot of other factors; symptoms of TIA can vary tremendously but they are quite similar to those of a major stroke. The most common symptoms which come on suddenly and with no forewarning are: difficulty speaking (aphasia) or putting the right words into sentences that make sense; confusion and disorientation; brief loss of sight in one or both eyes; severe weakness (hemiparesis), tingling and/or numbness (paresthesia) on one side of the body or the other; trouble walking, dizziness, loss of balance and/or coordination; partial loss of consciousness; and severe and agonizing headache; as well as paralysis of the face and tongue.
TIA is most often caused by a blockage (embolus) that shuts off the flow of blood in an artery of the brain. Such a blockage is usually caused by atherosclerotic plaque (fatty deposits) that breaks off and becomes lodged in a major artery in the head or neck. TIA can also be caused by a blood clot (thrombus) in the heart that is caused by atrial fibrillation (abnormal rhythm of the heart).
Other, less frequent, causes of TIA may be a variety of blood diseases that cause the blood to thicken. Also, TIA is somehow linked with hypertension (high blood pressure), a number of heart diseases, migraine headaches, tobacco use (smoking or chewing), high cholesterol and diabetes mellitus.
The first line of treatment for TIA is administration of anti-platelet drugs (such as aspirin, clopidogrel or ticlopidine) which prevent blood cells (platelets) from clotting. This treatment is then followed up with anticoagulatns (such as heparin and warfarin) which are also intended to prevent blood from clotting. Often anti-platelet drugs and anticoagulants are combined for quicker and more effective results. However it is essential to determine the cause of the TIA so that more specific treatments can then be prescribed.
In patients with moderate to severe narrowing of the neck arteries, a preventive surgical procedure called carotid endarterectomy is recommended in order to remove the built up plaque deposits.
In some cases carotid angioplasty or stenting is a feasible option and it involves the use of a ballooning device to open a clogged artery and then to insert a stent (a tube) which will keep it open.