To the Editor Dr Ebinger and colleagues1 reported that ambulance-based thrombolysis using the Stroke Emergency Mobile (STEMO) led to higher rates of tissue plasminogen activator (tPA) treatment and shorter alarm-to-treatment time in patients with acute ischemic stroke without increasing cerebral hemorrhage or mortality rate.
Ebinger et al1 randomly assigned weeks to STEMO deployment or usual care during the study period. However, it is questionable whether the results during the STEMO weeks and the control weeks were comparable. Patients were more likely to receive tPA treatment and be transported to hospitals with a stroke unit even without STEMO deployment during the STEMO weeks than during the control weeks (24.1% vs 21.1% and 90.7% [estimated] vs 87.3%, respectively).
Kwak MJ, Kim J. Ambulance-Based Thrombolysis in Acute Ischemic Stroke. JAMA. 2014;312(9):961. doi:10.1001/jama.2014.8369