Large Core Thrombectomy: Feasibility of Simplified Protocol in Resource-Limited Settings

Several trials have demonstrated the benefits of endovascular thrombectomy (EVT) for large-core strokes (Alberta Stroke Program Early CT [Computed Tomography] Score <6). However, its effectiveness in lower-middle-income countries with resource-limited settings remains uncertain. This study evaluated the feasibility of EVT for large-core strokes using a simplified imaging protocol with noncontrast CT and CT angiography in a resource-constrained environment.

We conducted a prospective, single-center, observational study at Da Nang Hospital, Vietnam (May 2023-May 2024). Patients with anterior circulation large-vessel occlusion strokes, Alberta Stroke Program Early CT Score <6 on noncontrast CT, admission National Institutes of Health Stroke Scale score ≥6, and EVT within 24 hours were included. The primary outcome was the modified Rankin Scale score at 90 days. Functional independence was defined as modified Rankin Scale score 0-2 and ambulatory independence as 0-3. Safety outcomes included symptomatic intracranial hemorrhage and 90-day mortality. Post-hoc indirect comparisons of ambulatory independence and mortality were made against the Large Stroke Therapy Evaluation EVT arm and the best medical treatment cohorts from 6 published "large core" randomized controlled trials.

Among 157 EVT-treated patients, 52 (33.1%) had Alberta Stroke Program Early CT Score <6. Median age was 62.5 years, and 57.7% were male. Median onset-to-hospital time was 4.1 hours, admission National Institutes of Health Stroke Scale score15, and initial Alberta Stroke Program Early CT Score was 4. Successful reperfusion (modified Treatment in Cerebral Infarction≥2b) was 78.9%. At 90 days, the median modified Rankin Scale score was 3.5. Functional and ambulatory independence were 23.1% and 50%, respectively. Symptomatic intracranial hemorrhage occurred in 9.6%, mortality was 25%. Successful reperfusion was the only independent predictor of ambulatory independence (odds ratio [OR], 14.7; 95% CI, 1.6-134). Indirect comparisons showed higher ambulatory independence in our cohort compared with the Large Stroke Therapy Evaluation EVT arm (50.0% versus 33.5%, P = 0.033) and the pooled best medical treatment cohort from 6 published randomized controlled trials (50.0% versus 19.89%, P<0.001), with no significant mortality difference.

EVT is feasible for patients with large-core stroke in lower-income countries using a simplified noncontrast CT -CTA protocol. Successful reperfusion is a key determinant of improved outcomes.

This study is a substudy of the multicenter PROMISE (Predictors of Good Outcomes in Thrombectomy for Large Infarct Core Stroke Evaluation) cohort, registered on ClinicalTrials.gov (NCT06016348, https://clinicaltrials.gov/study/NCT06016348), using data from patients enrolled at Da Nang Hospital.