NASHVILLE, TENN. – Fast thrombolytic treatment of acute ischemic stroke clearly helps patients, but being really, really fast is even better.
Patients treated with intravenous tissue plasminogen activator (tPA) within the first 60 minutes of their stroke onset, the putative “golden hour,” had significantly better outcomes at hospital discharge, compared with patients treated just an hour later, based on U.S. data from more than 65,000 acute ischemic stroke patients.
“In national U.S. clinical practice, treatment with intravenous tPA in the golden hour, compared with later, is associated with more frequent independent ambulation at discharge, discharge to home, and freedom from disability or dependence at discharge,” compared with patients treated at 61-180 minutes or later, Dr. Jeffrey L. Saver said at the International Stroke Conference.
“These findings support intensive efforts to accelerate patient presentation and treatment initiation, such as Target: Stroke Phase II and mobile CT ambulances, to maximize benefit of thrombolytic therapy for acute ischemic stroke,” said Dr. Saver, professor of neurology and director of the stroke center at the University of California, Los Angeles.
His study used data collected from 65,348 patients with acute ischemic stroke treated at any of 1,456 U.S. hospitals participating in the Get With the Guidelines–Stroke program during 2009-2013. Of those patients, 878 (1.3%) received tPA within the first hour following onset of their stroke, 10% within 61-90 minutes, 71% within 91-180 minutes, and 18% within 181-270 minutes.
Although the 878 patients treated within an hour of symptom onset constituted little more than 1% of all patients, the series was 10-fold larger than any prior report, which allowed a venture into “terra incognita” for insight into thrombolysis efficacy when used so early during a stroke, Dr. Saver noted. “Innovations in prehospital and emergency department systems increasingly enable intravenous tPA delivery in the first 60 minutes,” he said at the meeting, which was sponsored by the American Heart Association.
In a multivariate analysis that adjusted for many potential confounders, treatment in the first 60 minutes linked with statistically significant improvements, compared with patients treated at 1-4.5 hours, for several outcome measures at hospital discharge, including a 72% relative increase in being nondisabled – a modified Rankin score of 0 – and a 58% relative increase in being independent – a modified Rankin scale score of 0-2.
Dr. Saver highlighted how even a 30-minute drop in the time to treatment produced substantively better outcomes. The percentage of patients with a modified Rankin score of 0-1 at discharge was 38% in the 0- to 60-minute patients, 33% in those treated after 91-120 minutes had elapsed, and 28% in those treated 121-180 minutes after symptom onset.
Dr. Saver has been a consultant to BrainGate, Covidien, Grifols, and Stryker and has received research support from Covidien, Lundbeck, and Stryker.
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