Platelet Biomarkers in Patients with Atherosclerotic Extracranial Carotid Artery Stenosis: A Systematic Review

Factors associated with clopidogrel resistance and clinical outcomes in ischemic cerebrovascular disease: A retrospective study

OBJECTIVE

Clopidogrel resistance may lead to the recurrence of cerebrovascular diseases. We aimed to identify potential factors associated with clopidogrel resistance and evaluate the clinical outcomes of the patients.

MATERIALS AND METHODS

In this retrospective study, patients with ischemic cerebrovascular disease treated with clopidogrel were included and classified into 2 groups according to the adenosine diphosphate (ADP)-induced platelet aggregation. Patients with the ADP inhibition rate of <30 % were included in clopidogrel resistance group, otherwise were included in clopidogrel sensitive group. CYP2C19 genotype and other clinical data were analyzed to identify factors and clinical features in the multivariate analysis. The outcomes were vascular events in 6 months.

RESULTS

In total, 139 patients were enrolled with 81 (58.27 %) in clopidogrel sensitive group and 58 (41.73 %) in clopidogrel resistance group. Female and CYP2C19 *2*3 carrying were risk factors for clopidogrel resistance, and female was an independent risk factor (OR 2.481, 95 % CI 1.066-5.771, P=0.035). The clopidogrel resistance group showed a higher use rate of argatroban (P=0.030) and a lower arachidonic acid-induced inhibition of platelet aggregation (P=0.036). Clopidogrel resistance was related to the progressing stroke (HR 3.521, 95 % CI 1.352-9.170, P=0.010), but had no influence on the bleeding events (P>0.05).

CONCLUSIONS

The risk of clopidogrel resistance increased significantly in female patients. Patients with clopidogrel resistance may have an increased incidence of stroke progression in the acute phase.

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.