Does mild deficit for patients with stroke justify the use of intravenous tissue plasminogen activator?

Abstract

Intravenous (IV) tissue plasminogen activator (t-PA) is an effective medication currently used to treat acute ischemic stroke within 3 hours of symptom onset in patients with an identifiable clinical deficit measured using the National Institutes of Health Stroke Scale (NIHSS). Some reports suggest that patients with milder acute ischemic stroke may improve spontaneously and may not benefit additionally from IV thrombolysis. The objective of this retrospective study was to assess the outcomes of patients at our stroke center who received IV t-PA treatment for acute ischemic stroke, within 3 hours of symptom onset, outside the setting of a clinical trial and had a NIHSS score of less than or equal to 10 compared with historic control subjects. There were 52 patients who received IV t-PA for acute ischemic stroke. Of those, 31 (male 44% [n = 14]) had a NIHSS score of 10 or less (mean NIHSS score 6 +/- 2). The mean age was 61 +/- 14 years, the mean NIHSS score was 6 +/- 2, and the mean modified Rankin scale (mRS) score was 1.4 +/- 1.5. We identified 98 patients (male 74% [n = 73]) in the National Institute of Neurological Disorders and Stroke IV recombinant t-PA study placebo group. The mean age was 65 +/- 13 years, the mean NIHSS score was 7 +/- 2, and the mean mRS score was 2.5 +/- 1.7. Assuming equal variances, the mRS score at discharge, for the IV t-PA-treated group, demonstrated a better clinical outcome that was statistically significant (P < .009). This retrospective study demonstrates that administering IV t-PA to patients with a mild stroke, measuring 10 or less by the NIHSS, can lead to improved clinical outcome when compared with patients with similar NIHSS score who have not received similar treatment.