ABSTRACT
Background:@#High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease. We explored a predictive model of platelet reactivity to clopidogrel and the relationship with clinical outcomes.@*Methods:@#A total of 441 patients were included. Platelet reactivity was measured by light transmittance aggregometry after receiving dual antiplatelet therapy. HTPR was defined by the consensus cutoff of maximal platelet aggregation >46% by light transmittance aggregometry. CYP2C19 loss-of-function polymorphisms were identified by DNA microarray analysis. The data were compared by binary logistic regression to find the risk factors. The primary endpoint was major adverse clinical events (MACEs), and patients were followed for a median time of 29 months. Survival curves were constructed with Kaplan-Meier estimates and compared by logrank tests between the patients with HTPR and non-HTPR.@*Results:@#The rate of HTPR was 17.2%. Logistic regression identified the following predictors of HTPR: age, therapy regimen, body mass index, diabetes history, CYP2C19*2, or CYP2C19*3 variant. The area under the curve of receiver operating characteristic for the HTPR predictive model was 0.793 (95% confidence interval: 0.738–0.848). Kaplan-Meier analysis showed that patients with HTPR had a higher incidence of MACE than those with non-HTPR (21.1% vs. 9.9%; χ2 = 7.572, P = 0.010).@*Conclusions:@#Our results suggest that advanced age, higher body mass index, treatment with regular dual antiplatelet therapy, diabetes, and CYP2C19*2 or CYP2C19*3 carriers are significantly associated with HTPR to clopidogrel. The predictive model of HTPR has useful discrimination and good calibration and may predict long-term MACE.
ABSTRACT
Objective To compare the consistency of thrombelastography (TEG) and light transmittance aggregometry (LTA) in monitoring the antiplatelet therapy of the patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI),and observe the changes of mean platelet volume (MPV) of the patients treated with aspirin and clopidogrel after PCI.Methods A total of 177 patients undergoing PCI and the treatment of aspirin and clopidogrel in Peking University First Hospital during March 2014 and May 2015 were enrolled in the study.Their adenosine diphosphate (ADP) or arachidonic acid (AA) induced platelet inhibition rates determined by TEG,MPV before and after antiplatelet therapy,and the maximum platelet aggregation rates measured by LTA from 99 patients were retrospectively analyzed.Results There was no any correlation between the maximum aggregation rates measured by LTA and the platelet inhibition rates determined by TEG regardless of using ADP or AA as agonist (all P ＞ 0.05).The detection rates of clopidogrel hyporesponsiveness determined by LTA and TEG were 30.3％ and 45.5％,respectively,while those of aspirin hyporesponsiveness were 19.2％ and 31.3％,respectively.The detection rate of hyporesponsiveness determined by LTA was significant lower than that by TEG (P ＜ 0.05).The MPVs after antiplatelet therapy were significant lower than that before treatment (all P ＜ 0.01) regardless of clopidogrel hyporesponsive or sensitive and aspirin hyporesponsive or sensitive.The MPVs in clopidogrel hyporesponsive group before and after treatment were significantly lower than that in clopidogrel sensitive group (all P ＜ 0.05).The PLT counts in clopidogrel or aspirin hyporesponsive groups after treatment were significantly higher than that before treatment (all P ＜ 0.05).Conclusion There is poor correlation between LTA and TEG.It should be noted that the incidence rate of antiplatelet drug hyporesponsiveness is high in clinical practice.The MPVs of the patients significantly decrease after antiplatelet therapy.The patients with a significant increase of PLT after antiplatelet therapy are more likely to become drug hyporesponsiveness,while the patients with lower MPV are more likely to have clopidogrel hyporesponsiveness.