Effect of workflow metrics on clinical outcomes of low diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) patients subjected to mechanical thrombectomy

Endovascular treatment for anterior circulation large-vessel occlusion ischemic stroke with low ASPECTS: a systematic review and meta-analysis

BACKGROUND

Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with Alberta Stroke Program Early CT Score (ASPECTS) 0-5 has not yet proven safe and effective by clinical trials.

OBJECTIVES

The aim of the study was to assess whether EVT in AIS patients presenting with low ASPECTS is beneficial.

DESIGN

Systematic review and meta-analysis of available studies in accordance with the PRISMA statement.

DATA SOURCES AND METHODS

We have searched MEDLINE, the Cochrane Central Register of Controlled Trials, and reference lists of articles published until 28 May 2022 with the aim to calculate (1) modified Rankin scale (mRS) score 0-3 at 3 months, (2) mRS score 0-2 at 3 months, (3) symptomatic intracranial hemorrhage (sICH), and (3) mortality at 3 months.

RESULTS

Overall, 24 eligible studies were included in the meta-analysis, comprising a total of 2539 AIS patients with ASPECTS 0-5 treated with EVT. The pooled proportion of EVT-treated patients achieving mRS 0-3 at 3 months was calculated at 38.4%. The pooled proportion of EVT-treated patients achieving mRS 0-2 at 3 months was 25.7%. Regarding safety outcomes, sICH occurred in 12.8% of patients. The 3-month pooled mortality was 30%. In pairwise meta-analysis, patients treated with EVT had a higher likelihood of achieving mRS 0-3 at 3 months compared with patients treated with best medical therapy (BMT, OR: 2.41). sICH occurred more frequently in EVT-treated patients compared with the BMT-treated patients (OR: 2.30). Mortality at 3 months was not different between the two treatment groups (OR: 0.71).

CONCLUSION

EVT may be beneficial for AIS patients with low baseline ASPECTS despite an increased risk for sICH. Further data from randomized-controlled clinical trials are needed to elucidate the role of EVT in this subgroup of AIS patients.

REGISTRATION

The protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO; Registration Number: CRD42022334417.

Prediction of 90 day home time among patients with low baseline ASPECTS undergoing endovascular thrombectomy: results from Alberta's Provincial Stroke Registry (QuICR)

BACKGROUND

The benefit of endovascular thrombectomy (EVT) in stroke patients with a low baseline Alberta Stroke Program Early CT Score (ASPECTS, ≤5) is uncertain. We aim to use random forest regression modeling to predict 90 day home time in patients with low ASPECTS.

METHODS

We used the Quality Improvement and Clinical Research (QuICR) provincial stroke registry and administrative data from southern Alberta to identify patients who underwent EVT in our center from July 2015 to November 2020. Baseline ASPECTS on non-contrast CT and CT angiography data were scored by a two physician consensus. The primary outcome was the predicted 90 day home time (the number of nights a patient is back at their premorbid living situation without an increase in level of care within 90 days of the stroke) using random forests regression. Estimates were generated using 200 bootstrapped datasets. Covariate contribution to home time was determined using partial dependence plots.

RESULTS

Of 657 EVT patients, 85 (12.9%) had baseline ASPECTS ≤5 (mean age 70.9 years, 44.7% women, 93.9% good-moderate collaterals, 60% M1-middle cerebral artery occlusion). Using partial dependence estimates, mean predicted home times were similar in the low ASPECTS (44.3 days) versus higher ASPECTS (43.1) groups. Factors predicting lower 90 day home time in this population were diabetes mellitus (-8.8 days), hypertension (-5.7 days), and atrial fibrillation (-3.6 days). There was no meaningful difference in predicted 90 day home time by sex, baseline National Institutes of Health Stroke Severity Scale score, occlusion site, tandem lesion, collateral grade or thrombolysis.

CONCLUSIONS

Patients with low ASPECTS who are selected for EVT using demographic and clinical profiles similar to higher ASPECTS patients achieved comparable outcomes.

Low relative diffusion weighted image signal intensity can predict good prognosis after endovascular thrombectomy in patients with acute ischemic stroke

BACKGROUND

It is vital to identify a surrogate last-known-well time to perform proper endovascular thrombectomy in acute ischemic stroke; however, no established imaging biomarker can easily and quickly identify eligibility for endovascular thrombectomy and predict good clinical prognosis.

OBJECTIVE

To investigate whether low relative diffusion-weighted imaging (DWI) signal intensity can be used as a predictor of good clinical outcome after endovascular thrombectomy in patients with acute ischemic stroke.

METHODS

We retrospectively identified consecutive patients with acute ischemic stroke who were treated with endovascular thrombectomy within 24 hours of the last-known-well time and achieved successful recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b). Relative DWI signal intensity was calculated as DWI signal intensity in the infarcted area divided by DWI signal intensity in the contralateral hemisphere. Good prognosis was defined as a modified Rankin Scale score of 0-2 at 90 days after stroke onset (good prognosis group).

RESULTS

49 patients were included in the analysis. Relative DWI signal intensity was significantly lower in the group with good prognosis than in the those with poor prognosis (median (IQR) 1.32 (1.27-1.44) vs 1.56 (1.43-1.66); p<0.01), and the critical cut-off value for predicting good prognosis was 1.449 (area under the curve 0.78). Multiple logistic regression analysis revealed association of good prognosis after endovascular thrombectomy with low relative DWI signal intensity (OR=6.84; 95% CI 1.13 to 41.3; p=0.04).

CONCLUSIONS

Low relative DWI signal intensity was associated with good prognosis after endovascular thrombectomy. Its ability to predict good clinical outcome shows potential for determining patient suitability for endovascular thrombectomy.

Angiographic Baseline Proximal Thrombus Appearance of M1/M2 Occlusions in Mechanical Thrombectomy

PURPOSE

Analyzing stroke thrombi has proven to be valuable in prognostication and risk stratification of stroke etiology, reperfusion success and outcomes. The aim of this study was to test if the baseline appearance of the proximal thrombus on digital subtraction angiography (DSA) can predict these parameters in acute ischemic stroke patients treated with mechanical thrombectomy.

METHODS

The appearance of the most proximal part of the thrombus was determined based on DSA. Thrombus perviousness, density, and histology were measured beforehand as described previously. Baseline, technical, and outcome variables were compared using the χ²-test, analysis of variance and the Kruskal-Wallis test.

RESULTS

A total of 144 stroke patients with M1 and M2 occlusions could be included in this present study. Of the patients 60.4% had a cutoff, 27.1% a tapered, and 12.5% a meniscus/tram-track appearance of the thrombus on baseline DSA. The number of maneuvers was higher in the cutoff cohort (P = 0.003). Age (P = 0.777), female sex (P = 0.936), administration of intravenous thrombolysis (P = 0.364), percentage of M1 occlusions (P = 0.194), Alberta Stroke Program early computed tomography score (ASPECTS, P = 0.256), usage of balloon guide catheters (P = 0.367), general anesthesia (P = 0.184), procedure time (P = 0.214) and symptom onset to groin puncture time (P = 0.114) did not significantly differ. Alongside a lower National Institutes of Health scale (NIHSS) score on admission (P = 0.085), good functional outcome was favorable for the meniscus/tram-track cohort (P = 0.030). Stroke etiology according to the trial of Org 10172 in acute stroke treatment (TOAST) criteria as well as thrombus perviousness, density, and histology showed no association with the thrombus appearance.

CONCLUSION

Baseline cut off thrombus appearance predicts a higher number of thrombectomy maneuvers. In day to day practice this may prepare the neurointerventionalist for a more challenging endovascular procedure ahead. Stroke etiology, clinical outcomes and thrombus-specific characteristics did not show any associations with the thrombus appearance.