Treatment with tissue plasminogen activator in the first 60 minutes after onset is associated with optimal outcomes for patients with acute ischemic stroke, according to new research published in Circulation.
“These findings reinforce the importance of quality improvement programs to accelerate door-to-needle time, support further implementation of telemedicine systems enabling delivery of thrombolysis in rural and other front-line hospitals and provide impetus for further research on the use of mobile stroke unit ambulances equipped with [CT] scanners that enable faster, prehospital delivery of thrombolysis,” Joon-Tae Kim, MD, and colleagues wrote.
Researchers analyzed 65,384 patients with acute ischemic stroke from 1,456 sites who were treated with tissue plasminogen activator (tPA) within 4.5 hours of the onset of symptoms.
The median onset-to-treatment time was 141 minutes among the patients treated with tPA, 878 (1.3%) of whom were treated within the first 60 minutes.
Compared with treatment within 61 to 270 minutes, treatment within 60 minutes was associated with higher likelihood of discharge to home (adjusted OR = 1.25; 95% CI, 1.07-1.45), independent ambulation at discharge (adjusted OR = 1.22; 95% CI, 1.03-1.45) and freedom from disability (modified Rankin scale score 0-1) at discharge (adjusted OR = 1.72; 95% CI, 1.21-2.46), without higher percentage of complications due to hemorrhage or in-hospital mortality.
For discharge to home, there was a nonlinear decline in benefit of tPA from onset-to-treatment times of 20 to 270 minutes, with a rapid benefit loss over time in the initial 170 minutes (for every 15-minute delay, 10.5 fewer patients per 1,000 were discharged home), but a less steep decline in benefit between 171 and 270 minutes (for every 15-minute delay, 2.6 fewer patients per 1,000 were discharged home; adjusted P for nonlinearity = .34), Kim and colleagues wrote.
However, they wrote, for independent ambulation, the decline in benefit was linear within the 4.5-hour window (for every 15-minute delay, 9.6 fewer patients per 1,000 could walk independently at discharge), and the same was true for in-hospital mortality (for every 15-minute delay, 1.4 fewer patients per 1,000 survived to discharge).
“The present study highlights both the importance of rapid therapy and the challenge of achieving such therapy,” Mark J. Alberts, MD, vice chair of hospital neurology at UT Southwestern Medical Center in Dallas, wrote in a related editorial. “The saying that ‘time is brain’ is certainly true and every minute counts. Our patients are counting on us not to waste time or their brains.” – by Dave Quaile
Disclosure: Kim reports no relevant financial disclosures. Please see the full study for a list of the other researchers’ relevant financial disclosures. Alberts reports speaking and consulting for Genentech.