乌鸦传媒

PHOENIX -- Endovascular thrombectomy for large-core acute ischemic stroke improved long-term outcomes, the SELECT2 trial affirmed.

The intervention shifted the 1-year modified Rankin Scale (mRS) score distribution toward less disability compared with medical care alone (probability of superiority 0.59, 95% CI 0.53-0.64, generalized OR 1.43, 95% CI 1.14-1.78), Amrou Sarraj, MD, of University Hospital Cleveland Medical Center, reported at the American Stroke Association International Stroke Conference.

The number needed to treat was just six to improve mRS by 1 point for one patient.

"Our study, evaluating 1-year clinical outcomes from the SELECT2 trial, is the first to show that thrombectomy treatment effect was preserved in patients with large [ischemic] stroke up to 24 h from when they were last known to be well," the group noted in a paper released in .

"Taken together with previous evidence, this analysis shows that endovascular thrombectomy improves clinical outcomes and quality-of-life scores in patients with large [ischemic] stroke not only in the short term but also in the long term (at 1 year), and provides strong evidence to support the use of endovascular thrombectomy in patients with extensive [ischemic] changes on CT or perfusion imaging," Sarraj and colleagues wrote.

. "The endovascular thrombectomy of acute [ischemic] stroke is experiencing another new beginning, which will probably lead to broader indications for treatment, including patients with large [ischemic] lesions," wrote Arturo Consoli, MD, PhD, of Foch Hospital in Suresnes, France, and Benjamin Gory, MD, PhD, of the Université de Lorraine in Nancy, France.

The trial had been stopped early for superior efficacy of thrombectomy at the 90-day analysis. It and other previous trials have established the benefit of thrombectomy for large-core ischemic strokes in 90-day functional outcomes, but long-term impact had been uncertain, with a "considerably lower" proportion of patients independent in function and ambulation compared with the in populations with favorable imaging profiles and small to moderate ischemic core strokes.

"The timeline of recovery in patients with extensive stroke also differed, with a significantly lower proportion of patients showing marked neurological recovery within the first 24 h after stroke (compared with those with small core stroke)," Sarraj's group pointed out.

Indeed, they added: "In our study, more than a quarter of the patients with continued follow-up beyond 3 months showed at least a 1-point improvement in functional status on the mRS at 1 year. These findings provide evidence of continued improvement beyond the 3-month window."

SELECT2 was designed with the primary aim of looking beyond the first 6 months when most small core stroke recovery occurs, since complete recovery could take longer for patients with more severe brain injury.

The phase III trial randomized 352 patients at 31 hospitals in the United States, Canada, Spain, Switzerland, Australia, and New Zealand to open-label treatment with supportive medical care with or without endovascular thrombectomy within 24 hours of stroke onset. Participants were ages 18 to 85 years and were eligible if their ischemic stroke was due to proximal occlusion of the internal carotid artery or of the first segment of the middle cerebral artery and had a large ischemic core on non-contrast CT (Alberta Stroke Program Early CT Score [ASPECTS] 3-5) or at least 50 mL on CT perfusion and MRI.

For key secondary endpoints, thrombectomy made functional independence (mRS 0-2) 3.17-fold more likely at 1 year (24% vs 6%) and independent ambulation (mRS 0-3) 85% more likely (37% vs 18%), both statistically significant differences from medical care alone.

Notably, "the proportion of patients requiring continuous nursing care (mRS 5) remained lower in patients receiving thrombectomy (8%) than in those receiving medical care only (14%), and of similar magnitude to the proportion of mRS 5 outcomes after endovascular thrombectomy at 90 days (8%)," Sarraj's group wrote.

Patients in the thrombectomy group also showed higher quality of life scores at 1-year follow-up. All-cause mortality trended the same direction without reaching statistical significance (45% vs 52% at 1 year, RR 0.89, 95% 0.71-1.11).

"We did not find any evidence of significant difference in thrombectomy treatment effect based on age, stroke severity, time from last known to have been well to [randomization], ASPECTS score, core volume estimates, and mismatch status, although patients enrolled at non-U.S. sites had lower point estimates of treatment effect than those enrolled at U.S. sites," the researchers noted.

As far as limitations, there was 6.5% loss to follow-up at 1 year that "could still be considered acceptable compared with other trials" and some "potentially relevant" adverse event data not collected beyond 90 days, the editorial pointed out. "Furthermore, the absence of data on the duration and type of rehabilitation protocol could limit the interpretation of the results, since these aspects could have a major role in the extended follow-up windows after the [ischemic] event; however, data for patients with large volume strokes are poorly available," they added.

"Therefore, to provide an appropriate clinical assessment for patients with large volume strokes, a long-term follow-up beyond the standard 3-month evaluation should be carefully considered in the design of new studies and trials that will have an impact on future guidelines," they wrote.