TIA is an acronym for the medical condition known as Transient Ischemic Attack.
A TIA, also known as a “mini-stroke” or a “brain attack,” is a short-lived occurrence of physical symptoms that are suggestive of a stroke that resolve (go away) within 24 hours but sometimes within minutes and often in less than an hour. These symptoms can include numbness/weakness limited to one side of the body; difficulty speaking or swallowing; visual disturbances or temporary blindness that is also limited to one eye, and a loss of coordination or balance.
The symptoms of a TIA are the result of a temporary obstruction in blood flow to a specific area of the brain. These obstructions are usually small blood clots that form within, and then detach from, areas of atherosclerosis (irregular collections of cholesterol and related lipids) in one or more arteries that provide the brain's blood supply. Most often, the sources of these small clots, or emboli, are within the carotid arteries of the neck. Other potential sources for emboli are the heart itself when an irregular heartbeat known as atrial fibrillation is present, and in certain relatively uncommon defects in heart structure that are present at birth but are not detected until adulthood.
Many medical conditions are known to be associated with both TIA and a “full” (complete) stroke. These include smoking, high blood pressure, diabetes, abnormal levels of cholesterol and lipids in the bloodstream, and a family history of stroke or heart disease. Of note is the much higher rate of stroke in those that have a previously diagnosis of heart disease and/or poor arterial circulation in the legs (“PAD,” Peripheral Arterial Disease).
Many long term public health studies have shown that, after a single TIA, the risk of suffering a complete stroke within a year is about 1 in 10, or 10%. In light of these statistics, the importance of a complete medical evaluation as soon as possible after a TIA occurs cannot be overemphasized.
Once a diagnosis of TIA is established, the goal of medical therapy is directed at immediate smoking cessation (if necessary), blood pressure control, medications such as aspirin and clopidogrel (Plavix), and one of the “statins” to lower the lipid level in the bloodstream.
In summary, a TIA is the result of a temporary obstruction of blood flow to a small area of the brain. Since it is impossible to distinguish a TIA from a full stroke immediately following the onset of symptoms, a TIA represents a medical emergency which is best dealt with by local emergency response personnel and immediate transportation to an appropriate medical treatment center.