Russell Mitesh Cerejo, MD
Dr. Mariano Espinosa de Rueda and colleagues couldn’t have chosen a better time to publish this paper. With the positive endovascular trials, we can move beyond the age old question – does this work? As this paper aptly points out, it is now time to determine who best benefits from endovascular therapy. Their study over a 2 year period, analyzed 150 patients who underwent endovascular recanalization for ischemic stroke. Patients were divided into a good outcome (mRS ≤2) and a futile recanalization (mRS >2) group at 3 months. The authors analyzed different modalities of imaging data. Fifty seven percent patients had a bad outcome and were noted to have a higher NIHSS, were older and had hypertension. With regards to imaging, the bad outcome group had a lower Alberta Stroke Program Early CT Score (ASPECTS) score on the non-contrast head CT, CT Angiogram Source Imaging (CTA-SI), cerebral blood volume (CBV), cerebral blood flow (CBF), and mismatch CBV-CBF ASPECTS. They also found a higher proportion of bad collaterals in this population. In univariate analysis low ASPECTS and poor-collaterals were associated with futile recanalization. However in the multivariate analysis CTA-SI, CBV ASPECTS and poor collaterals were associated with poor outcomes. Based on this they created a 3 variable scoring system with CTA-SI, CBV and Collaterals (see figure) to predict futile recanalization. In the reclassification analysis this scoring method added complimentary information to their test model.
This study sheds light on the current issue of appropriate patient selection for endovascular thrombectomy for ischemic stroke. Given the myriad of variables that account for a good or bad outcome in ischemic stroke, we need to streamline our efforts to evaluate which are the most reliable. Another challenge in acute stroke treatment is the race against time – these variables should be easily calculated, precise and leave no room for ambiguity. Most centers today use CT and CTA technology to identify candidates for acute stroke therapy and this scoring may be a useful, quick step to help triage the patient. Further prospective studies with a control arm would be useful.
We really appreciate Dr Russell Mitesh Cerejo comments about our paper. There are however some mistakes in the blog text that are probably related to typography but we would like to clarify to avoid misleadings:
– "Fifty seven percent patients had a BAD outcome (instead of good) and were noted to have a higher NIHSS, were older and had hypertension".
– "With regards to imaging, the BAD outcome group had a lower Alberta Stroke Program Early CT Score (ASPECTS) score on the non-contrast head CT, CT Angiogram Source Imaging (CTA-SI), cerebral blood volume (CBV), cerebral blood flow (CBF), and mismatch CBV-CBF ASPECTS"
– "They also found a higher proportion of BAD collaterals in this population".
Dr. Mariano Espinosa de Rueda, MD.