High On-Treatment Platelet Reactivity to Adenosine Diphosphate Predicts Ischemic Events of Minor Stroke and Transient Ischemic Attack.

BACKGROUND: This study aimed to evaluate the relationship between thromboelastography adenosine diphosphate maximum amplitude (TEG-ADPMA ) and recurrent ischemic events in patients with minor ischemic stroke or high-risk transient ischemic attack (TIA).

METHODS: A total of 265 patients received dual antiplatelet therapy were consecutively enrolled. High on-treatment platelet reactivity (HTPR) to ADP was assessed by TEG-ADPMA and detected the CYP2C19 genotype; recurrent ischemic events were followed up for 90 days after onset. The difference of recurrent ischemic events was analyzed with or without HTPR to ADP by the Kaplan-Meier, and further to determine the difference of recurrent ischemic events in each group according to TEG-ADPMA -based tertile distribution.

RESULTS: A total of 23 (8.6%) patients had recurrent ischemic events. TEG-ADPMA greater than or equal to 48 mm had good predictive value. Whether these patients were divided into 2 groups or 3 groups, the HTPR to ADP group had higher risk of recurrent ischemic events than the normal on-treatment platelet reactivity to ADP group by the Kaplan-Meier (all, P < .05). The tertile distribution map showed that the results of recurrent ischemic events were statistically significant in the third tertile group compared with the other two groups (all, P < .03); also, the third tertile group had a higher rate of carriers of at least 1 CYP2C19 reduced-function allele than the other two groups (P < .05).

CONCLUSIONS: In patients with minor ischemic stroke and high-risk TIA, the TEG-ADPMA could predict recurrent ischemic events and has auxiliary effect on clinical decision-making.