Abstract P779: Monocyte to Lymphocyte Ratio in Clot Analysis is a Marker of Cardioembolic Stroke Etiology

Abstract

Methods: We analyzed data from 190 patients in a prospective unicentric study. Thrombi obtained in emergent endovascular treatment ( EVT) were analyzed by MFC order to calculate the percentage of granulocytes , monocytes and lymphocytes, over total leukocyte population as well as monocyte-to-lymphocyte ratio ( MLR) Clinical and interventional parameters were recorded for each patient. Stroke subtypes were defined by the Trial of ORG 10172 in Acute Stroke Treatment classification. We tested MFC predictors of high risk cardioembolic strokes (HR CE) in patients with undetermined stroke etiology . MFC predictor was obtained by comparison of clots due to Large Arterial Atherosclerosis compared with clots due to HR CE. Results: Among 190 clots retrieved, 163 cases were properly analized. 91 cases with known stroke etiology after EVT and 72 cases of Undetermined stroke. In a demographic (age, gender) and EVT matched (time, tpa, number of passes) case -control study of 56 patients: HR CE strokes (28 cases) and LAA strokes (28 cases), the proportion of monocytes ( OR 1.06 , 95% CI 1.01- 1.11) and MLR ( OR 1.83 , 95% CI 1.12- 2.98) independently predicted HR CE detection. A cut-off point of 1.77% in a receiver operating characteristic curve predicted cardiomebolic etiology with sensitivity of 71% and specificity of 82%. Among Undetermined Strokes (n=72) the percentage of HR CE detection was higher in patients with high MLR (n=40 ; 74%) compared with low MLR (n=6; 33%) ( p< 0.001). Patients with high MLR were older than low MLR cases, although MLR > 1.77 independently predicted HR CE detection among Undetermined strokes (OR, 4.50 ,95% CI 1.35-15.04) in a multivariate model adjusted for age. Conclusion: Measurement of monocyte to lymphocyte ratio in clots by multiparametric flow cytometry detected patients at high risk of hidden cardioembolic origin among undetermined stroke population.