Each year, as many as 500,000 Americans experience mini strokes called transient ischemic attacks (TIAs).
Symptoms quickly go away, usually within an hour, and many people don't seek treatment. But 10 to 15 percent of people who experience TIAs will experience full-blown strokes within three months, and 40 percent of these strokes will occur in the first 24 hours, according to an article by three Loyola University Medical Center neurologists in the journal Expert Review of Neurotherapeutics.
Rapid evaluation and treatment of TIA patients, either in the emergency room or in specially designed TIA clinics, can reduce the risk of subsequent strokes, according to authors Farrukh Chaudhry, MD, Jose Biller, MD and Murray Flaster, MD, PhD.
A TIA is caused by a temporary blockage, typically a blood clot, in a blood vessel in the brain. Symptoms are similar to that of a stroke, including numbness or paralysis on one side of the body, vision changes, trouble speaking, difficulty with balance or walking, sudden severe headache, etc.
Blood clots that trigger TIAs can arise from atherosclerosis (hardening of the arteries), heart attacks and abnormal heart rhythms.
Advances in imaging techniques such as MRIs have improved diagnostic accuracy in patients. And rapid treatment following TIAs can reduce the risk of stroke by about 80 percent, according to two studies, one in Britain and one in France. These studies "are suggestive but not fully conclusive," the authors write. "Better study designs are needed to prove this vital point."