Endovascular Treatment Improves Functional Outcomes for Acute Basilar Artery Occlusion
Although it showed better functional outcomes, endovascular thrombectomy for the treatment of stroke because of basilar-artery occlusion was associated with procedural complications and intracerebral hemorrhage.
Raul G. Nogueira, MD
Recent findings published in the New England Journal of Medicine, from the multicenter randomized controlled trial, ATTENTION (NCT04751708), showed that approximately one-third of patients who received intravenous thrombolysis (IVT) with endovascular thrombectomy (EVT) within 12 hours after stroke onset had better functional outcomes at 90 days than best medical care among Chinese patients with basilar-artery occlusion (BAO).1
At 90 days, good functional status was reported in 104 patients (46%) in the EVT group and in 26 (23%) in the control group (adjusted rate ratio, 2.06; 95% CI, 1.46-2.91, P <.001). Notably, symptomatic intracranial hemorrhage occurred in 12 patients (5%) in the EVT group and none in the control group.
These findings were presented as an oral presentation in the clinical trials plenary session at the 2023 American Academy of Neurology (AAN) Annual Meeting, April 22-27, in Boston, Massachusetts, by lead author Raul G. Nogueira, MD, professor of neurology at the University of Pittsburgh (UP) and director of the UP Medical Center Stroke Institute, in Pennsylvania.2
The trial consisted of patients on EVT for BOA from 36 centers in China. The patients were randomly assigned in a 2:1 ratio within 12 hours after the estimated time of BOA to receive EVT or best medical care, which served as the control. The primary outcome was good functional status, which was defined as a score ranging from 0 to 3 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]), at 90 days. The secondary outcomes included a modified Rankin scale score ranging from 0 to 2, distribution across the scale score categories, and quality of life. Additionally, safety outcomes measures assessed were symptomatic intracranial hemorrhage at 24 to 72 hours, 90-day mortality, and procedural complications.
Among the 507 patients who underwent screening, 340 were in the intention-to-treat population, with 226 assigned to the EVT group and 114 to the control group. IVT was used in 31% of the patients in the EVT group and in 34% of those in the control group. Results for the secondary clinical and imaging outcomes were generally in the same direction as those for the primary outcome. Mortality at 90 days was 37% in the EVT group and 55% in the control group (adjusted risk ratio, 0.66; 95% CI, 0.52-0.82). Procedural complications occurred in 14% of the patients in the EVT group, including one death due to arterial perforation.
The trial limitations included that it exclusively enrolled Chinese patients, thus the results may not be generalizable to Western countries. Also, Nogueira and colleagues noted that the results are not generalizable for patients with milder stroke or who present beyond 12 hours after the estimated time of BAO. Since most patients in China are required to pay in advance for IVT, authors noted this may have led to the relatively low use of the therapy, contributing to a poorer outcome in the control group.
In previous research conducted by Nogueira, data suggested that the COVID-19 pandemic was associated with a global decline in stroke hospitalizations, IVT, and interfacility IVT transfers. Researchers observed that stroke admissions declined by 11.5% (95% CI, –11.7 to –11.3; P <.0001), IVT therapies declined by 13.2% (95% CI, –13.8 to –12.7; P <.0001), and interfacility IVT transfers decreased by 11.9% (95% CI, –13.7 to –10.3; P = .001) during the pandemic months.3
In the prior study was a cross-sectional, observational, retrospective analysis across 457 stroke centers in 70 countries across 6 continents. Investigators observed that there were 82,465 stroke hospitalizations and 12,527 IVT therapies performed in the 4 months in the prior year to the pandemic (March 2019 to June 2019), 91,373 stroke hospitalizations and 13,334 IVT therapies performed in the 4 months prior to the pandemic (November 2019 to February 2020), and 80,894 stroke hospitalizations and 11,570 IVT therapies performed during the first 4 months of the pandemic (March 2020 to June 2020).
Decline in stroke hospitalization pre- and early-pandemic varied geographically, with a 7.1% drop in Asia (95% CI, –7.4 to –6.9; P <.0001), a 18.8% drop in North America (95% CI, –19.3 to –18.3; P <.0001), a 10.0% drop in Europe (95% CI, –10.4 to –9.6; P <.0001), a 17.4% drop in South America (95% CI, –18.5 to –16.3; P <.0001), and a 30.2% drop in Africa (95% CI, –32.2 to –28.3; P <.0001). Stroke hospitalizations did not significantly fall in Oceania. Primary stroke centers (PSCs; 89 centers) experienced a decline of 17.3% (95% CI, –17.9 to –16.7) compared to comprehensive stroke centers (CSCs; 236 centers) which experienced a decline of 10.3% (95% CI, –10.6 to –10.1).
IVT therapies declined by 13.2% (95% CI, –13.8 to –12.7; P <.0001) between pre- and early-pandemic, with a median monthly IVT volume per center of 6.2 (IQR, 2.8-12.0) pre-pandemic and 5.3 (IQR, 2.0-10.5; P <.001) at 389 centers in the early-pandemic period. IVT declined by 10.1% in Asia (95% CI, –11.2 to –9.1; P <.0001), 14.4% in North America (95% CI, –15.6 to –13.3; P <.0001), 13.4% in Europe (95% CI, –14.3 to –12.5; P <.0001), 24.2% in South America (95% CI, –27.6 to –21.0; P <.0001), and 23.5% in Africa (95% CI, –29.8 to –18.2; P <.01) during this time period. Again, no significant drops were seen in Oceania. IVT declines were greater in PSCs (–15.5% [95% CI, –16.9 to –14.2]; 138 centers) versus CSCs (–12.6% [95% CI, –13.3 to –12.0]; 251 centers; P = .0001).
Click here for more coverage of AAN 2023.
