Abstract 420: The Correlation of Whole Blood Viscosity and Outcome in Mechanical Thrombectomy for Acute Ischemic Stroke

Introduction Whole blood viscosity (WBV), reflecting the intrinsic resistance of blood flow, is an established predictor of stroke events in individuals. This study aims to correlate the WBV at different shear rates with the outcome of endovascular thrombectomy, known to be an effective treatment for large vessel occlusion (LVO) stroke. Methods This is a single‐center retrospective study conducted at our comprehensive stroke center. The charts of 317 patients who underwent endovascular thrombectomy within 6 hours of LVO stroke were reviewed. The modified Rankin score (mRS) at discharge was used as the outcome measure, with individuals categorized as low (0‐2) or high (3‐6). WBV at different shear rates was calculated using De Simone's Formula, dependent on hematocrit and total protein levels. The T‐test and Chi‐square test were used to compare baseline quantitative and categorical data, respectively, amongst the mRS study groups. We elaborated multivariable logistic regression analyses to identify the independent risk factors associated with the outcome of interest following mechanical thrombectomy. Finally, Spearman rank order correlation was used to assess for r between mRS and WBV at different shear rates. Results Baseline group characteristics, constituted by variables pertaining to demographics and medical history, were similar across the two study groups. However, our study found no significant differences in clinical outcomes between the two groups with WBV at high shear rate (OR 0.969, 95% CI 0.77‐1.204, p = 0.780) and low shear rate (OR 0.998, 95% CI 0.988‐1.008, p = 0.779) following mechanical thrombectomy. Spearman rank order correlation between WBV at high shear rate (r=0.058, p=0.123) and low shear rate (r=0.048, p=0.128) was non‐significant. Conclusion This is one of the few studies to evaluate the effect of WBV at high and low shear rates on the clinical outcome of endovascular thrombectomy in patients with LVO. Our results revealed that WBV at high and low shear rates did not affect the outcome of endovascular thrombectomy, as measured by mRS at discharge. We propose that different components of blood viscosity may uniquely affect blood flow, and our study provides a path for future research to further study the correlation.