[Subtypes of acute ischemic stroke and neurological prognosis].

Background: TOAST diagnosis is used in acute ischemic stroke. There is no evidence about the relationship between stroke subtypes classified by TOAST diagnosis and prognosis. We investigated prognosis of cardioembolic stroke (CE) and atherothrombotic stroke (AT) after intravenous recombinant tissue plasminogen activator (rt-PA), to clarify relationship between stroke subtypes and prognosis. Additionally we investigated acute ischemic stroke with internal carotid artery occlusion as a factor to influence the prognosis.

Methods: We analyzed 37 patients (22 cardioembolic stroke cases and 15 atherothrombotic stroke cases) with acute ischemic stroke who received intravenous rt-PA within 3 hours after onset. We performed neurologic evaluation using the National Institutes of Health Stroke Scale (NIHSS) on admission, after 24 hours, and at discharge. We evaluated the efficacy of rt-PA on the basis of NIHSS score at 24 hours. We also assessed the prognosis by measuring modified Rankin Scale (mRS) at 3 months. We performed classification by presence or absence of internal carotid artery occlusion in 37 cases, examining the prognosis using mRS at 3 months.

Results: There was a significant difference in NIHSS on admission between CE and AT, but significant difference was not found in NIHSS at 24 hours, and at discharge. There was also no significant difference in the proportion of effectiveness after rt-PA therapy and mRS at 3 months. The cases with internal carotid artery occlusion were associated with lower mRS score as compared with the cases without occlusion.

Conclusions: Stroke subtypes classified by TOAST diagnosis have no relationship with the prognosis. However, internal carotid artery occlusion is a factor associated with unfavorable outcome.