Clinical characteristics of transient ischemic attacks in black patients.

We analyzed the clinical, CT, and angiographic findings in 50 black patients with carotid transient ischemic attacks (TIAs). Thirty-two percent had TIAs lasting less than 1 hour, 26% had TIAs lasting 1 to 6 hours, and 42% had TIAs lasting 6 to 24 hours. Fifty-two percent of TIA patients had CT evidence of cerebral infarction despite complete clinical recovery. CT was abnormal in two of 16 (13%) patients with TIAs lasting less than 1 hour; however, CT was abnormal in 24 of 34 (70%) patients with TIAs lasting longer than 1 hour. Angiographic findings of extracranial carotid disease appropriate to TIA symptoms were present in 12 (24%) patients. Two patients in whom the TIA episode lasted less than 1 hour later had clinical cerebral infarction, whereas 20 patients with longer-duration TIAs developed ischemic stroke within 4 months. Of these black TIA patients, 22 (44%) developed clinical cerebral infarction.