Results of Intravenous Thrombolysis Within 4.5 to 6 Hours and Updated Results Within 3 to 4.5 Hours of Onset of Acute Ischemic Stroke Recorded in the Safe Implementation of Treatment in Stroke International Stroke Thrombolysis Register (SITS-ISTR) An Observational Study

JAMA Neurol: 7/1/13

Importance  Pooled analysis of randomized controlled trials of intravenous thrombolysis shows no statistically significant benefit beyond 4.5 hours, with the possible advantage perhaps offset by risk.

Objective  To compare the outcomes of patients who were treated within 4.5 to 6 hours or within 3 to 4.5 hours of the onset of an ischemic stroke with the outcomes of patients who were treated within 3 hours in the SITS-ISTR.

Design  An observational study based on SITS-ISTR data during the period from 2002 to 2011.

Setting  Acute and emergency care.

Participants  Of 29 618 patients with acute ischemic stroke, 283 (1.0%) were treated within 4.5 to 6 hours of onset, 4056 (13.7%) were within 3 to 4.5 hours of onset, and 25 279 (85.4%) were treated within 3 hours of onset, in compliance with other European Union approval criteria.

Exposure  Intravenous thrombolysis with alteplase. Read more