Combination of endovascular therapy with standard medical therapy had no significant beneficial effect compared with standard medical therapy alone in patients with acute strokes due to vertebrobasilar artery occlusion, according to study results published in The Lancet Neurology.
While there is evidence supporting the beneficial effect of mechanical thrombectomy for acute stroke secondary to large vessel occlusion of the anterior circulation, limited data are available regarding the safety and efficacy of this treatment for acute strokes secondary to vertebrobasilal artery occlusion.
The multicenter randomized open-label trial included patients presenting to 28 centers in China within 8 hours of vertebrobasilar occlusion. The patients were randomly allocated (1:1 ratio) to receive either endovascular treatment with standard medical therapy (intervention group) or standard medical therapy alone (control group).
The primary outcome was a modified Rankin scale (mRS) score of ≤3 at 90 days, assessed on an intention-to-treat basis. The primary safety outcome was mortality at 90 days.
Between April 27, 2015 and September 27, 2017, the researchers assessed 288 patients for trial eligibility and included 131 patients in the trial. Of these, 66 were included in the intervention group and 65 in the control group. The study was terminated prematurely by the steering committee on the recommendation of the data and safety monitoring board because of excessive crossovers and progressive drop in the average rate of valid per centre recruitment.
For the primary end point analysis in the intention-to-treat population, there was no difference in the percentage of patients with mRS ≤3 at 90 days between the intervention and the control group (42% vs 32%, respectively, P =.23).
To assess the effect of crossovers between treatment groups, secondary prespecified analyses in the per-protocol population and the as-treated population were completed. In patients who actually received mechanical thrombectomy compared with patients who received standard medical therapy alone, rates of mRS≤3 at 90 days were higher in the per-protocol (44% vs 25% of patients, respectively; adjusted odds ratio [aOR] 2.90, 95% CI, 1.20-7.03) and in the as-treated (47% vs 24%, respectively; aOR 3.02, 95% CI, 1.31-7.00) populations.
While the rate of symptomatic intracranial hemorrhage within 24 hours of randomization was numerically higher in the intervention group, this was not a statistically significant difference. No difference in 90-day mortality was noted between the groups.
The researchers concluded that “our data confirm the poor outcomes of untreated patients presenting with acute vertebrobasilar occlusion and severe clinical findings.” but go on to add that these data “support the overall safety and potential efficacy of early endovascular treatment in this patient population.”
Liu X, Dai Q, Ye R, et al. Endovascular treatment versus standard medical treatment for vertebrobasilar artery occlusion (BEST): an open-label, randomised controlled trial [published online ahead of print, 2019 Dec 9]. Lancet Neurol. doi:10.1016/S1474-4422(19)30395-3