By Matthew E. Fink, MD

Louis and Gertrude Feil Professor and Chair, Department of Neurology, Associate Dean for Clinical Affairs, New York Presbyterian/Weill Cornell Medical College

Dr. Fink reports no financial relationships relevant to this field of study.

SOURCE: Writing group for the BASILAR Group; Zi W, Qiu Z, Wu D, et al. Assessment of endovascular treatment for acute basilar artery occlusion via a nationwide prospective registry. JAMA Neurol 2020;77:561-573.

Basilar artery occlusion is a rare but devastating medical condition that accounts for approximately 1% of all ischemic strokes and 5% of large vessel occlusions. The vast majority of patients with basilar artery occlusion remain severely disabled or die, and earlier studies evaluating the benefits of endovascular thrombectomy with first-generation devices showed poor results. In addition, several other prospective, randomized studies that were organized in recent years were unable to reach completion because of small numbers and the tendency to withhold patients from the trials and move directly to intervention. BASILAR is a nonrandomized cohort study, looking at endovascular thrombectomy for acute basilar occlusion in a nationwide prospective registry of consecutive patients presenting to 47 comprehensive stroke centers across 15 provinces in China between 2014 and 2019.

Patients had to start treatment within 24 hours of onset of symptoms to be eligible for the trial. Patients were divided into two groups; the first group received standard medical treatment plus endovascular therapy, and the second group received standard medical treatment alone. The primary outcome was improvement in the modified Rankin Scale scores at 90 days, assessing odds ratios, and adjusting for pre-specified prognostic factors. The secondary outcome measure was favorable functional outcome as defined by a modified Rankin Scale score of 3 or less at 90 days. Safety outcomes included mortality and symptomatic intracerebral hemorrhage at 90 days. One thousand two hundred fifty-four patients were screened and 829 patients were recruited into the study; 73.8% of the study patients were men. Six hundred forty-seven were treated with standard medical treatment plus endovascular therapy and 182 were treated with standard medical treatment alone. At 90 days, the group treated with endovascular therapy had better outcomes, with an adjusted odds ratio (OR) of 3.08, P < 0.001. Endovascular therapy also was associated with a higher rate of 90-day Rankin scores of < 3 with an OR of 4.70, P < 0.001. Endovascular treated patients also had a lower 90-day mortality, despite an increase in symptomatic intracerebral hemorrhage (7.1% vs. 0.5%, P < 0.001).

In conclusion, patients with acute basilar artery occlusion treated by endovascular therapy within 24 hours of occlusion time had better functional outcomes and reduced mortality compared to those treated with medical therapy alone.