ASPECTS-based selection for late endovascular treatment: a retrospective two-site cohort study

Abstract

Introduction The DAWN trial demonstrated the effectiveness of late endovascular treatment (EVT) in acute ischemic stroke (AIS) patients selected on the basis of a clinical-core mismatch. We explored in a real-world sample of EVT patients if a clinical-ASPECTS (Alberta Stroke Program Early CT Score) mismatch was associated with an outcome benefit after late EVT. Methods We retrospectively analysed all consecutive AIS patients admitted 6-24 hours after last proof of good health in two stroke centres, with initial National Institutes of Health Stroke Scale (NIHSS) ≥10 and an internal carotid artery or M1 occlusion. We defined clinical-ASPECTS mismatch as NIHSS≥10 and ASPECTS≥7, or NIHSS≥20 and ASPECTS≥5. We assessed the interaction between clinical-ASPECTS mismatch positive and negative patients and late EVT, using ordinal shift analysis of the 3-month modified Rankin Scale and adjusting for multiple confounders. Results The included 337 patients had a median age of 73 years (IQR=61-82), admission NIHSS of 18 (15-22) and baseline ASPECTS of 7 (5-9). Out of 196 (58.2%) patients showing clinical-ASPECTS mismatch, 146 (74.5%) underwent late EVT. Among 141 (41.8%) mismatch negative patients, late EVT was performed in 72 (51.1%) patients. In the adjusted analysis, late EVT was significantly associated with a better outcome in the presence of clinical-ASPECTS mismatch (adjusted Odd Ratio, aOR=2.83; 95% confidence interval, CI: 1.48-5.58) but not in its absence (aOR=1.32; 95%CI: 0.61-2.84). The p-value for the interaction term between clinical-ASPECTS mismatch and late EVT was 0.073. Conclusions In our retrospective two-site analysis, late EVT seemed effective in the presence of a clinical-ASPECTS mismatch, but not in its absence. If confirmed in randomized trials, this finding could support the use of an ASPECTS-based selection for late EVT decisions, obviating the need for advanced imaging.

Noncontrast Computed Tomography vs Computed Tomography Perfusion or Magnetic Resonance Imaging Selection in Late Presentation of Stroke With Large-Vessel Occlusion

“…In a 2-site analysis of patients in the extended time window in Switzerland, MT was effective in the presence of a clinical-ASPECTS mismatch as defined by the DAWN study criteria but not effective in its absence. Another study suggested that NCCT-ASPECTS–based selection paradigms for late MT have similar 90-day outcomes as the DAWN and DEFUSE-3 studies. In a network of stroke centers in Houston, Texas, hospitals with NCCT as the initial imaging choice were more likely to perform MT than hospitals with NCCT and CTP as the primary approach, without any difference in clinical outcomes.…”

Acute stroke imaging selection for mechanical thrombectomy in the extended time window: is it time to go back to basics? A review of current evidence

“…One out of 18 studies prospectively recruited patients 47. The majority of the remaining studies (n=13) conducted post-hoc analyses of prospective trial data or endovascular therapy registries, that is, patient and imaging characteristics were retrospectively reviewed according to different predefined triage models and reported along with efficacy and safety outcomes 48–59. Four studies reported observational data from clinical practice,60–63 and one study analysed pooled data from several randomised clinical trials 64.…”

“…Studies providing group comparisons adhered to either of two principle study designs: (1) patients meeting the criteria of a basic imaging paradigm presenting 6–24 hours after stroke onset (basic LATE -group) were compared with patients routinely selected for endovascular therapy without the use of advanced imaging within 6 hours of stroke onset (basic EARLY -group) according to guidelines (n=5),47 49 52 60 62 or (2) within 6–24 hours after stroke onset, patients who fulfilled basic imaging criteria (late BASIC -group) were compared with patients meeting perfusion imaging criteria (late CTP -group) that matched or closely referred to the DAWN/DEFUSE3 selection criteria (n=10) 48 50 53–60 63. Seven studies additionally reported outcome data of patients not treated with endovascular therapy 47 48 51 53 55 58 64…”

“…In eight studies, the basic triage models included so-called ‘clinical imaging mismatches’ defined by different NIHSS and ASPECTS thresholds ranging from ASPECTS≥7 and NIHSS score≥12 to ASPECTS≥5 and NIHSS score≥20 48 49 51–54 56 59. Three studies utilised pure imaging-based paradigms including ASPECTS and collateral circulation measures 55 57 58.…”

“…As per our review inclusion criteria, all studies reported as primary outcome the rates of functional independence (mRS 0–2) at 90 days. Rates of sICH were reported in 12 studies47 49–53 56 59–63 and the 90 day mortality rate in 9 studies 47 50 55–57 59 61 63 64…”