European Journal of Cardiovascular Medicine

Background: Acute Coronary syndrome (ACS) in diabetic patients is associated with an increased overall risk of stent thrombosis compared to the general ACS population. In many centers worldwide the routinely used antiplatelet agent in most settings is still clopidogrel. It is generally recognized that many patients exhibit a diminished response to Clopidogrel. The study aimed to verify whether clopidogrel response measured by MEA in response to ADP, in diabetic ACS patients treated with PCI predicts the risk of stent thrombosis and bleeding. Methods:  In this prospective observational study, consecutive diabetic patients admitted with ACS who were treated by successful PCI with stent implantation and started on Clopidogrel as a second antiplatelet agent were included. ADP-induced platelet reactivity assessment was performed directly before patient discharge using a Multiplate electrode analyzer with ADP as an inducer. The cutoff value for high platelet reactivity was considered as greater than 468 AU * min and less than 188 AU * min for very low platelet reactivity, based on the consensus of the Working Group On treatment platelet reactivity. Results:  Out of n=100 members included in the study most of the patients were having single vessel disease (62%) and 38% had double vessel disease. 30% of the study population showed high platelet reactivity and 14% were having low platelet reactivity. Stent thrombosis developed in 6% of patients, of which 4% had definite stent thrombosis and 2% had probable stent thrombosis. Out of n=6 patients with stent thrombosis, 4 cases showed high platelet reactivity with an odds ratio of 5.23 (0.90-30.29) and a P value of 0.0064. N=8 patients developed bleeding of which 2 were major and 6 minor. Out of n=8 patients with bleeding n=4 cases were having low platelet reactivity with an odds ratio of 6.538 (0.38-111.09) with a P value of 0.001 which was statistically significant for major bleeding Conclusion: This study shows that in a high-risk population of patients with ACS and diabetes treated with stent implantation and receiving clopidogrel, higher on-treatment platelet reactivity (HPR) is related to increased risk of stent thrombosis and low platelet reactivity (LPR) to increased risk of bleeding at 1-year follow-up.