Controversies about treatment 3-4.5 hours after acute stroke: Lessons from the ECASS III trial re-analysis in the pursuit of the truth, and the implications for practice guidelines
Dr. Lehana Thabane
Stroke is a devastating disease with over 400,000 Canadians living with the effects of stroke. Alteplase is one of the thrombolytic medications by the FDA, Health Canada, and other regulators for early treatment for stroke within 3 hrs of symptom onset based on the NINDS-II trial. Beyond 3 hrs, the evidence is mixed. The ECASS III was the only trial that showed significant benefit at 3-4.5 hrs from symptom onset; but it also showed an increase in harm. However, Alteplase is widely used in practice because of the “strong” recommendations by many national clinical guidelines. One of the key criticisms for the ECASS III trial results was that the significant result of benefit was not adjusted for baseline imbalance on some key prognostic factors. We re-analysed the original ECASS III data adjusting for key baseline imbalances using multiple methods. Our findings show no significant benefits and continue to find significant risks with alteplase 3–4.5 hours after stroke. In this talk, I will share some key lessons from the ECASS III re-analysis on how to use the scientific method in the pursuit of truth, and the implications for clinical practice guidelines.