Comparison of Partial (.6 mg/kg) versus Full-Dose (.9 mg/kg) Intravenous Recombinant Tissue Plasminogen Activator Followed by Endovascular Treatment for Acute Ischemic Stroke: A Meta-Analysis

BACKGROUND In the treatment of acute ischemic stroke, intravenous (IV) recombinant tissue plasminogen (rt-PA) and intraarterial (IA) interventions are often combined. However, the optimal dose of IV rt-PA preceding endovascular treatment has not been established. METHODS Studies that used combined IV and IA thrombolysis were identified from a search of the MEDLINE, PubMed, and Cochrane databases. We compared the rates of angiographic recanalization, symptomatic intracerebral hemorrhage (sICH), and favorable functional outcome between patients who had been treated with .6 mg/kg IV rt-PA and those who had received .9 mg/kg rt-PA. RESULTS Eleven studies met our criteria. In 7 studies, .6 mg/kg IV rt-PA had been administered to 317 patients, whereas 140 patients in 4 studies had received .9 mg/kg of IV rt-PA. The weighted mean of median National Institutes of Health Stroke Scale score at presentation was 18.3 in the .6 mg/kg group (median range 9-34), and 17.3 in the .9 mg/kg group (median range 4-39). Patients in the .9 mg/kg group had higher rates of favorable outcome [odds ratio (OR) = 1.60, 95% confidence interval (CI) = (1.07-2.40), P = .022] and similar rates of sICH [OR = .86 (95% CI .41-1.83), P = .70]. Depending on the statistics used, the higher angiographic recanalization rate among patients treated with .9 mg/kg was significant (P = .03, events/trial syntax logistic regression) or borderline significant (P = .07, random effects model). CONCLUSION Our analysis suggests that using .9 mg/kg IV rt-PA prior to IA thrombolysis is safe and may be associated with higher recanalization rates and better functional outcome at 3 months.