Extending Therapeutic Window for Intravenous Thrombolysis to 4.5 Hours Remains Safe and Effective in Asian Acute Ischemic Stroke Patients (P02.196)

Objective: We evaluate the efficacy and safety of intravenous tissue plasminogen activator (IV-TPA) in an extended therapeutic window (3-4.5 hours) among Asian patients in Singapore. Background IV-TPA remains the only approved therapy for acute ischemic stroke (AIS) within 3 hours of onset, although meta-analysis of previous IV-TPA trials and confirmation in a randomized trial (ECASS-III), demonstrate benefit until 4.5 hours. Use of IV-TPA remains low in Asian populations, mainly due to Patients9 late arrival and higher anticipated bleeding risk. Design/Methods: AIS patients receiving IV-TPA (0.9mg/Kg body weight) in standardized protocols between Jan 2007 to March 20010 were studied prospectively at National University Hospital, Singapore. Efficacy was assessed with functional outcomes at 3-months (modified Rankin Scale Score: Good outcome (0-1) and poor outcome (2-6)) and safety by rates of symptomatic intracranial hemorrhage (SICH). Results: 224/2271 (9%) of patients (mean age 63±12 years; 131 (59%) males; mean onset-to-treatment time 157±38 minutes and median National Institute of Health Stroke Scale (NIHSS) 16 points) admitted with AIS were treated with RT-TPA during the study period. 190 (85%) were treated 3 hours had poorer outcomes at 3 months (62% versus 46%), although this was not statistically significant (OR 1.87;95%CI 0.88-3.96, p=0.097). SICH occurred in 9 (4%) patients and although higher (9.7% versus 3.3%, p=0.141) at 3-4.5 hours, this did not reach significance. Conclusions: IV-tPA in an extended therapeutic window is effective and safe in AIS in our multiethnic Asian population in Singapore. Disclosure: Dr. Yeo has nothing to disclose. Dr. Paliwal has nothing to disclose. Dr. Wakerley has nothing to disclose. Dr. Ahmad has nothing to disclose. Dr. Ng has nothing to disclose. Dr. Pei Kee has nothing to disclose. Dr. Hock Luen has nothing to disclose. Dr. Chan has nothing to disclose. Dr. Sharma has nothing to disclose.