The faster the revascularization, the better the outcomes after stroke, a SWIFT PRIME substudy confirms.
Patients undergoing stent retriever therapy had a 91% probability of functional independence if they were reperfused within 150 minutes of symptom onset. The first hour of delay corresponded with a 10% drop in these odds — and every hour thereafter saw a 20% reduction.
Patients who presented directly to an endovascular-capable center, as opposed to initially arriving at a referring facility, waited less between symptom onset to groin puncture (179.5 versus 275 minutes, P<0.001), Mayank Goyal, MD, of the University of Calgary, Alberta, and co-authors reported in Radiology.
Time from arrival at the emergency department to arterial access took a median of 90 minutes overall, and took 129 minutes to reperfusion among participating stroke centers with efficient work flows.
“Fast reperfusion leads to improved functional outcome among patients with acute stroke treated with stent retrievers. Detailed attention to workflow with iterative feedback and aggressive time goals may have contributed to efficient workflow environments,” according to the researchers.
“That’s really important because it confirms what we’ve seen in other studies,” Donald F. Frei, MD, of Swedish Medical Center in Denver, said. “It shows that for every hour you waste there’s a large loss in potential good outcomes for the patients,” Frei, who was not involved in the study, told MedPage Today in a phone interview.
“Aggressive time metrics and frequent feedback likely played a key role in maintaining efficiency,” the investigators suggested. “Targets for further improvement include patient triage and transport at referring facilities, efficient imaging paradigms and consent processes, and procedural times in patients with difficult anatomy.”
The idea of treating strokes as quickly as possible after onset is well accepted now clinically, commented Philip M. Meyers, MD, of New York-Presbyterian Hospital/Columbia University Medical Center in New York City.
“It’s like ‘don’t drink and drive’ and ‘don’t smoke cigarettes,’” he told MedPage Today.
Goyal’s SWIFT PRIME substudy included 196 stroke patients who were randomized to IV thrombolysis with or without the addition of Solitaire stent retriever therapy. Participating institutions kept records of workflow times.
Most patients who got mechanical thrombectomy did so without general anesthesia (64%). Centers offering routine general anesthesia did not show a lag in time from arrival at the emergency department to groin puncture (89 minutes versus 95.5 minutes for conscious sedation, P=0.76).
Similarly, severe vessel tortuosity (42 minutes versus 38 minutes for nonsevere tortuosity, P=0.86) and left-sided lesions (38 minutes versus 34.5 minutes for right-sided lesions, P=0.12) failed to increase the groin puncture-to-reperfusion time.
When it came to their limitations, the authors noted that “all the participating centers were chosen on the basis of their experience and patient volume. As such, the results may not be generalizable to all centers that offer endovascular treatment for acute stroke.”
Nonetheless, “the results of this study highlight the importance of tracking endovascular workflow times and providing feedback to maintain good results in the acute management of stroke. To achieve the outcomes observed in SWIFT PRIME in routine practice, quality improvement target interval times will need to match more closely and preferably exceed the time intervals achieved in the trial,” they wrote.
Meyers pointed out that Goyal has been making his point for a long time. “He beats his drum and the mantra is ‘time is brain,’” he said. “And until you know otherwise for patients, it’s true. We should hurry to treat them as quickly as possible.”
“It could be the kind of stroke where it’s already too late, or it’s the kind where if you move quickly enough you can save them. It could also be the kind where there’s time to mess around and do other things and maybe even get dinner,” Meyers noted.
“But you don’t know — so you’d better move fast.”
The SWIFT PRIME trial was sponsored by Covidien.
Goyal disclosed relationships with Covidien, GE Healthcare, Medtronic, Microvention, Quikflo Health, and Stryker.
Frei declared consulting for Codman, Microvention, Penumbra, Siemens, and Stryker. He was also a co-investigator for the ESCAPE trial.
Meyers reported no relevant conflicts of interest.
Goyal M, et al “Analysis of workflow and time to treatment and the effects on outcome in endovascular treatment of acute ischemic stroke: results from the SWIFT PRIME randomized controlled trial” Radiology 2016; DOI: 10.1148/radiol.2016160204.