Citations

Abstract Background: Most clots retrieved from patients with acute ischemic stroke are ‘red’ in color and are predominantly composed of red blood cells and fibrin. ‘White’ clots represent a less common entity and their histological composition is largely unknown.The aim of this study was to investigate the composition, imaging and procedural characteristics of ‘white’ clots retrieved by mechanical thrombectomy.Materials and Methods:Nineteen ‘white’ thrombi selected by visual inspection from 293 cases were collected as part of the multi-institutional RESTORE registry. Non-contrast computed tomography (NCCT), histological and immunohistochemical analyses were performed. Components were quantified using Orbit Image Analysis.Results:Quantification of Martius Scarlett Blue stain identified platelets/other as the major component in ‘white’ clots’ (63%) followed by fibrin (26%), red blood cells (7%) and white blood cells (4%). ‘White’ clots presented significantly more platelets/other and less red blood cells compared to the ‘red’ clots which showed a mean of 23% and 44%, respectively. The mean platelet (CD42b) content in ‘white’ clots was 43%; von Willebrand Factor (vWF) mean expression was 38%.Collagen and calcification were associated in one case. Fatty acid binding protein 4 was expressed in two cases.‘White’ clots were also significantly smaller (9.5 versus 12 mm) and less hyperdense (52 versus 61 Hounsfield Units) on NCCT compared to the other cases.Conclusions:‘White’ clots represented 6% of our cohort and are platelet and vWF-rich. Calcification, collagen and adipocytes were found occasionally. ‘White’ clots differ from other clots in composition, size and density on NCCT.

Background To assess if leukoaraiosis severity is associated with outcome in patients with acute ischemic stroke (AIS) following endovascular thrombectomy, and to propose a leukoaraiosis-related modification to the ASPECTS score. Methods A retrospective review was completed of AIS patients that underwent mechanical thrombectomy for anterior circulation large vessel occlusion. The primary outcome measure was 90-day mRS. A proposed Leukoaraiosis-ASPECTS (“L-ASPECTS”) was calculated by subtracting from the traditional ASPECT based on leukoaraiosis severity (1 point subtracted if mild, 2 if moderate, 3 if severe). L-ASEPCTS score performance was validated using a consecutive cohort of 75 AIS LVO patients. Results 174 patients were included in this retrospective analysis: average age: 68.0±9.1. 28 (16.1%) had no leukoaraiosis, 66 (37.9%) had mild, 62 (35.6%) had moderate, and 18 (10.3%) had severe. Leukoaraiosis severity was associated with worse 90-day mRS among all patients (P=0.0005). Both L-ASPECTS and ASPECTS were associated with poor outcomes, but the area under the curve (AUC) was higher with L-ASPECTS (P<0.0001 and AUC=0.7 for L-ASPECTS; P=0.04 and AUC=0.59 for ASPECTS). In the validation cohort, the AUC for L-ASPECTS was 0.79 while the AUC for ASPECTS was 0.70. Of patients that had successful reperfusion (mTICI 2b/3), the AUC for traditional ASPECTS in predicting good functional outcome was 0.80: AUC for L-ASPECTS was 0.89. Conclusions Leukoaraiosis severity on pre-mechanical thrombectomy NCCT is associated with worse 90-day outcome in patients with AIS following endovascular recanalization, and is an independent risk factor for worse outcomes. A proposed L-ASPECTS score had stronger association with outcome than the traditional ASPECTS score.

Abstract The severe acute respiratory syndrome coronavirus 2 pandemic of 2019 to 2020 has resulted in multiple hospitalizations, deaths, and economic hardships worldwide. Although respiratory involvement in patients with coronavirus disease 2019 ( COVID ‐19) is well known, the potential cardiovascular and cerebrovascular manifestations are less understood. We performed a PubMed and Google Scholar search and reviewed relevant literature on COVID ‐19 and cardiovascular system involvement. Severe acute respiratory syndrome coronavirus 2 possesses high affinity for angiotensin‐converting enzyme 2 receptor, which is highly concentrated in the lungs and cardiovascular tissue, thereby provoking concern for cardiovascular involvement in COVID ‐19 cases. Preexisting cardiovascular and cerebrovascular disease has been shown in previous reports to be a risk factor for severe infection. On the basis of our review of published studies, COVID ‐19 patients may be more likely to experience acute cardiac injury, arrhythmia, coagulation defects, and acute stroke and are likely to have poorer outcomes as a result. As the COVID ‐19 pandemic continues, more data about potential cardiovascular and cerebrovascular manifestations of the disease are required.

Purpose Compare functional outcomes of acute ischemic stroke patients undergoing embolectomy with either local anesthesia or conscious sedation. Secondarily, identify differences in hemodynamic parameters and complication rates between groups. Materials and methods Single institution, retrospective review of all acute ischemic stroke patients undergoing embolectomy between January 2014 and July 2018 ( n = 185). Patients receiving general anesthesia ( n = 27) were excluded. One-hundred and eleven of 158 (70.3%) composed the local anesthesia group, and 47 (29.7%) composed the conscious sedation group. Median age was 71 years (interquartile range 59–79). Seventy-eight (49.4%) were male. The median National Institute of Health stroke scale score was 17.5 (interquartile range 11–21). Hemodynamic, medication, complication, and functional outcome data were collected from the anesthesia protocol and medical records. Good functional outcome was defined as a three-month modified Rankin Scale < 2. A multivariate analysis was performed to estimate the association of anesthesia type on three-month modified Rankin Scale score. Results Three-month modified Rankin Scale score <2 was similar between groups ( p = 0.5). Patients receiving conscious sedation were on average younger than patients receiving local anesthesia ( p = 0.01). Conscious sedation patients were more likely to receive intravenous thrombolytic prior to embolectomy ( p = 0.025). The complication rate and hemodynamic parameters were similar between groups. Conclusion Functional outcome of acute ischemic stroke patients undergoing embolectomy appears to be similar for patients receiving local anesthesia and conscious sedation. This similarity may be beneficial to a future study comparing general anesthesia to local anesthesia and conscious sedation. The use of local anesthesia or conscious sedation does not significantly impact hemodynamic status.

Background and purpose The Alberta Stroke Program Early CT Score (ASPECTS) is a commonly used scoring system to select patients with stroke for endovascular treatment (EVT). However, the inter- and intra-reader variability is high. Objective To determine whether the inter- and intra-reader variability is different for various regions of the ASPECTS scoring system by evaluating the interobserver variability of ASPECTS between different readers in a per-region analysis. Materials and methods All patients with acute ischemic stroke who proceeded to EVT in our institutions over a 4-year period were retrospectively identified from a prospectively maintained database. Images were reviewed by two experienced neuroradiologists, who recalculated the ASPECTS independently. We examined each region of the ASPECTS system to evaluate agreement between the raters in each area. Results 375 patients were included. The median total ASPECTS was 9 (IQR 8–9). The most common region showing ischemic change was the insula, with the M6 region being least commonly affected. Overall interobserver agreement for ASPECTS using Cohen’s κ was 0.56 (95% CI 0.51 to 0.61). The region with the highest agreement was the insula (κ=0.56; 0.48 to 0.64). The region with the lowest agreement was M3 (κ=0.34; 0.12 to 0.56). Agreement was relatively good when ASPECTS were dichotomized into 0–5 versus 6–10 (κ=0.66; 0.49 to 0.84). Conclusions Substantial interobserver variability is found when calculating ASPECTS. This variability is region dependent, and practitioners should take this into account when using ASPECTS for treatment decisions in patients with acute stroke.