Essential investigations of patients with suspected TIAs.

Transient ischemic attacks (TIAs) are warning episodes predicting that such patients are at high risk for stroke which potentially could be life-threatening or leave an individual with substantial disability. TIAs result from large or small vessel disease, cardiogenic embolic events and hematological abnormalities. The patient's past and current medical history provides necessary clues suggesting which investigational tests should be conducted. Every patient presenting with a TIA should have a total blood count, electrocardiogram, and a brain imaging study. Patients with anterior circulation symptoms should undergo noninvasive carotid testing, usually by carotid duplex ultrasonography, to determine if there is a surgically remediable carotid stenosis. Patients with posterior circulation TIAs should undergo magnetic resonance angiography (MRA) or a conventional arteriogram which, if positive, may be an indication for anti-platelet or anticoagulation therapy. Other testing depends on the presumptive etiology of the TIA. In general, a TIA should be considered as a serious warning of impending stroke that requires rapid and efficient investigations to define and remedy the reasons for the cerebral ischemic events. TIAs by definition may last up to 24 h, but usually are self-terminating after a few minutes. They are a serious warning of possible future strokes that may result in substantial morbidity and mortality. Once TIAs are diagnosed, the major goal is to reduce the risk of future strokes. Patients with TIAs usually present in the Emergency Room or doctor's office. They may seek immediate medical care or relate the history of the TIA during a routine visit. As soon as a diagnosis of a TIA is considered, a careful past and current medical history should be taken to substantiate the diagnosis. Conditions which mimic TIAs need to enter into the differential diagnosis and, if necessary, be ruled out. For example, a Todd's transient paralysis can follow a partial focal seizure. Migraine auras may also mimic TIAs, particularly in the elderly. Any space-occupying lesions and arteriovenous malfunction may first present with a TIA-like complaint. Peripheral nerve disease must be recognized since it can cause transient weakness and/or numbness affecting one limb.