Transient Ischemic Attacks

Focal neurologic abnormalities of sudden onset and brief duration caused by cerebrovascular disease.

Transient ischemic attacks (TIAs) are due to temporary blockage of blood flow to the brain. By definition, they last <= 24 hours; > 75% last < 5 minutes, but some last several hours.

TIAs can be a warning sign of impending stroke. About one third of persons who have had at least one TIA will have a stroke, and having had a TIA increases the risk of stroke by 9.5. Thus, detection of a TIA and identification of its cause are essential.

Symptoms develop rapidly. They are identical to those of a stroke but are temporary and do not cause permanent damage (see Table 44-3). Questioning about TIA symptoms should be systematic and specific; information about temporary prickling or loss of feeling in the arms or legs, temporary limp or other walking problems, sensation of a shade or curtain coming over one eye, and recent new-onset headache should be sought. Treatment depends on the vascular cause, as it does for patients with ischemic stroke.