Historical Reference Page
This is a historical reference page. This trial preceded the modern evidence base. It is presented as a predecessor reference. See ATTENTION (2022) for the modern successor trial that established endovascular thrombectomy for basilar artery occlusion.
BEST Trial: Basilar Artery Occlusion: Endovascular Intervention vs Standard Medical Treatment
In patients with acute basilar artery occlusion within 8 hours, does endovascular thrombectomy improve 90-day favorable functional outcome (mRS 0-3) compared with best medical management?
Liu et al. (Lancet Neurol 2020) · doi:10.1016/S1474-4422(19)30395-3 · 131 patients
Population
Included
- Age 18 years or older (no upper age limit)
- Acute ischemic stroke consistent with infarction in the basilar artery territory
- Basilar artery occlusion confirmed by CTA, MRA, or DSA, within 8 hours of estimated occlusion time
- Written informed consent from the patient or a surrogate
- Ability to undergo EVT at study center
Excluded
- Intracranial hemorrhage on baseline CT or MRI
- Premorbid mRS 3 or greater
- Uncontrolled hypertension (systolic above 185 mmHg or diastolic above 110 mmHg) not controllable except with continuous parenteral therapy
- Hemorrhagic diathesis, coagulation factor deficiency, or oral anticoagulation with INR above 1.7
- Life expectancy less than 1 year
Primary Outcome: mRS 0-3 at 90 Days (ITT)
131 patients; endovascular thrombectomy vs best medical management; basilar artery occlusion
In 131 patients with basilar artery occlusion confirmed by CTA, MRA, or DSA, randomized at 28 Chinese centers, endovascular thrombectomy did not significantly improve favorable functional outcome (mRS 0-3) at 90 days in the intention-to-treat analysis. mRS 0-3 was achieved in 42% of the EVT group versus 32% of the medical management group (OR 1.74, 95% CI 0.81 to 3.74, P=0.23). The trial was terminated early after enrolling 131 of 344 planned patients (38% of target) due to slow enrollment and high crossover: 14 of 65 patients (22%) randomized to medical management crossed over to EVT, substantially diluting the ITT analysis toward the null. A per-protocol analysis was nominally significant (OR 2.90, 95% CI 1.20 to 7.03, P=0.016), which is hypothesis-generating given the early termination and crossover contamination.
Visualization not shown for predecessor reference pages. See source paper for figures.
Trial Design
BEST enrolled patients with basilar artery occlusion confirmed by CTA, MRA, or DSA at 28 Chinese stroke centers between April 2015 and September 2017. Patients within 8 hours of symptom onset (or last known well) were randomized 1:1 to EVT (any available stent retriever or aspiration device) or best medical management (including IV alteplase at 0.9 mg/kg if eligible). Enrollment was hampered because physicians and families were reluctant to accept randomization to medical management alone for a high-mortality condition when EVT was available; 14 of 65 medical-arm patients (22%) crossed over, leading to termination at 131 of 344 planned participants. Crossover diluted the ITT analysis toward the null; per-protocol analysis showed nominal significance.
Safety
Symptomatic intracranial hemorrhage occurred in 5 of 66 EVT patients (7.6%) versus 0 of 65 medical patients. Mortality at 90 days was 33% (22 of 66) with EVT versus 38% (25 of 65) with medical management (P=0.54). The elevated sICH rate in the EVT arm reflects reperfusion hemorrhage in basilar territory.
Trial lineage
Endovascular therapy for basilar artery occlusion
BEST and BASICS were the first two RCTs in basilar-artery occlusion and both failed their primary frame, driven by substantial crossover in BEST and a control arm in BASICS that frequently received alteplase. ATTENTION and BAOCHE, both in Chinese populations, established benefit in 0-12 h and 6-24 h windows respectively and shifted guideline support toward EVT for basilar LVO.
- 2020BEST Trial· this pageNEUTRAL
First RCT of EVT for basilar artery occlusion. ITT primary (mRS 0-3 at 90 days): 42% vs 32% (OR 1.74, CI 0.81–3.74, p=0.23). Terminated early for crossover and low enrollment. Preceded ATTENTION (2022).
- 2021BASICS TrialNEUTRAL
Multinational RCT of EVT for basilar artery occlusion within 6 hours. Primary (mRS 0-3 at 90 days): 44.2% EVT vs 37.7% medical (RR 1.18, CI 0.92–1.50, P=0.19). Statistically negative; CI did not rule out meaningful benefit. Preceded ATTENTION (2022).
- 2022ATTENTION TrialPOSITIVE
Basilar artery thrombectomy within 12 hours; China trial.
- 2022BAOCHE TrialPOSITIVE
Basilar EVT 6–24 hours with imaging selection.