Association of Impedance Aggregometry-Measured Platelet Aggregation With Thromboembolic Events in Patients Who Undergo Carotid Endarterectomy: A Pilot Study

Objectives: The aim of the current study was to assess the relationship among thrombin receptor activator peptide 6 (TRAP test), adenosine-5′-diphosphate (ADP test), arachidonic acid (ASPI test), and stroke/transient ischemic attack (TIA), using the multiple electrode aggregometry (Multiplate) in patients undergoing carotid thromboendarterectomy (CEA). Design: A retrospective study. Setting: Vascular surgery operating rooms of a university hospital. Participants: One hundred thirty-one out of 474 patients undergoing CEA between November 2020 and October 2022. Interventions: None. Measurements and Main Results: A preoperative blood sample of all enrolled patients was analyzed using the Multiplate analyzer. Receiver operating characteristics curves, were generated to test the ability of TRAP, ADP, and ASPI in discriminating perioperative thromboembolic stroke/TIA. A logistic LASSO regression model was used to identify factors independently associated with stroke/TIA. Eight patients experienced a perioperative stroke/TIA. Although all the platelet functional assays showed excellent predictive performance, an ADP value exceeding 72 U showed the highest specificity (87%) and sensitivity (68%) in discriminating patients who had a perioperative thromboembolic stroke/TIA, with a negative predictive value of 99% and a positive predictive value of 15%. After LASSO regression, an ADP >72 U and the need for a shunt during CEA were the only 2 variables independently associated with perioperative stroke/TIA. Conclusion: Because the ADP test was independently associated with perioperative stroke/TIA, the assessment of platelet reactivity using Multiplate may offer potential utility in monitoring patients undergoing CEA.