Abstract 3174: Intravenous Thrombolysis in 3-4.5 hours: Utilization and outcomes Analysis of the Minnesota Stroke Registry
Background: The results of the third European Cooperative Acute Stroke Study (ECASS 3) demonstrated that intravenous (IV) thrombolysis for acute ischemic stroke (AIS) improved patient outcomes when administered within 3-4.5 hours (hrs) after symptom onset. We analyzed data from the Minnesota Stroke Registry to assess the rates of IV thrombolytic utilization in this expanded window and examine outcomes of patients treated within the 3-4.5 hrs window.
Methods: We identified patients who had received IV recombinant tissue plasminogen activator (rt-PA) at any of the 19 participating hospitals from Jan 1, 2008 till Dec 31, 2010. Treatment groups were those actually treated by IV rt-PA in 0-3 hrs and those treated by IV rt-PA in 3-4.5 hrs. We compared the rates of unfavorable outcome (inability to ambulate independently with or without assisting device at discharge) and in-hospital mortality among patients treated with IV rt-PA within 3-4.5 hrs to those who received IV rt-PA within the conventional 0-3 hrs window.
Results: Out of the total 519 patients who received IV rt-PA for AIS, 433 (83%) were treated within 0-3 hrs and 86 (17%) within 3-4.5 hrs. Adjusting for age, sex, and “adverse initial examination findings” (reduced level of consciousness, aphasia, and weakness), there was a trend towards higher rates of unfavorable outcome at discharge among those treated within 3-4.5 hrs compared to those treated within 0-3 hrs time window (Odds ratio [OR], 1.76; 95% confidence interval [CI], 0.95 to 3.26). In hospital mortality did not differ between the 3-4.5 hrs groups and 0-3 hrs groups (OR, 1.05; 95% CI, 0.38 to 2.96). Incidence of symptomatic intracerebral hemorrhage was non-significantly lower in the 3-4.5 hrs group compared to the 0-3 hrs group (2.3% vs.4.6%, p=0.34).
Conclusion: Patients who received IV rt-PA within the 3-4.5 hrs window comprised 17% of all IV rt-PA cases treated in the MSR hospitals after guidelines recommended time window expansion. Outcomes of these patients were comparable to those treated within 3 hours of symptom onset.
- © 2012 by American Heart Association, Inc.