Better functional outcome
The primary outcome was the score on the mRS at 90 days. Results showed a shift in the distribution of scores on the mRS at 90 days toward better outcomes favoring endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval [CI], 1.11-1.69; P = .004).
The efficacy of endovascular therapy with respect to the primary outcome was similar across predefined subgroups and across all trial sites. However, the trial was not powered to allow definite conclusions based on the results of subgroup analyses.
Although patients with an ASPECT score of 0-2 (indicating very large infarct cores) are considered unlikely to benefit from endovascular treatment, the researchers did find some signals of gain for these patients.
“Although no conclusions can be drawn because the trial was not powered for this analysis and the confidence interval for the odds ratio between the trial groups included 1, there may have been a benefit with endovascular therapy in this subgroup,” the authors wrote. “More trials are warranted to determine if this benefit is valid.”
As for secondary outcomes, the percentage of patients with a score of 0-2 on the mRS at 90 days was 30.0% in the endovascular therapy group and 11.6% in the medical management group (relative risk [RR], 2.62; 95% CI, 1.69-4.06).
The percentage of patients with a score of 0-3 on the mRS at 90 days was 47.0% in the endovascular therapy group and 33.3% in the medical management group (RR, 1.50; 95% CI, 1.17-1.91).
The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours, which occurred in 6.1% of the endovascular therapy group, compared to 2.7% in the medical management group (RR, 2.07; 95% CI, 0.79-5.41; P = .12)
Mortality within 90 days was 21.7% in the endovascular therapy group and 20.0% in the medical management group. Other serious adverse events occurred in 40.0% in the endovascular therapy group and 38.2% in the medical management group (P = .70).
The percentage of patients receiving IV thrombolysis was relatively low, which may have affected outcomes in the medical management group. Another potential limitation was that urokinase rather than alteplase, which is probably more effective, was used for thrombolysis in a small percentage of patients.
Further, the study did not include patients older than 80 years or those with an ASPECT value greater than 5 and infarct core volume of 70-100 mL, and it included only Chinese patients, so the results may not be generalizable, the researchers noted.
These findings will likely change clinical practice, said Dr. Huo, who noted that the current guideline doesn’t provide “a high-level recommendation” for [endovascular therapy] in patients with a low ASPECT score.
“These new results will change the guideline” to suggest endovascular therapy for large-core patients, he said.
Welcome news
An accompanying editorial by Pierre Fayad, MD, department of neurological sciences, division of vascular neurology and stroke, University of Nebraska Medical Center, Omaha, welcomed results from this and other recent related studies.
From these new results, “it is reasonable to suggest that endovascular thrombectomy be offered to patients with large strokes” if they arrive in a timely fashion at a center capable of performing the procedure and have an ASPECT value of 3-5 or an ischemic-core volume of 50 mL or greater, he wrote.
“The improved chance of independent walking and the ability to perform other daily activities in patients with the most severe strokes is welcome news for patients and for the field of stroke treatment.”
The study received funding from Covidien Healthcare International Trading (Shanghai), Johnson & Johnson MedTech, Genesis MedTech (Shanghai), and Shanghai HeartCare Medical Technology. Dr. Huo and Dr. Jovin report no relevant financial relationships.
A version of this article first appeared on Medscape.com.