The Pursuit of Clinically Relevant Measures of Platelet Function After Antiplatelet Drug Therapy⁎⁎Editorials published in the Journal of the American College of Cardiology reflect the views of the authors and do not necessarily represent the views of JACC or the American College of Cardiology

Thrombus and antiplatelet therapy in type 2 diabetes mellitus. A prospective study after non-ST elevation acute coronary syndrome and a randomised, blinded, placebo-controlled study in stable angina

Type 2 diabetes mellitus (T2DM) is associated with higher rates of thrombotic complications in patients with coronary artery disease (CAD) despite optimal medical therapy. Thrombus area was measured in T2DM and non-diabetic patients receiving aspirin and clopidogrel 7-10 days after troponin positive Non ST-elevation acute coronary syndrome (NSTE-ACS). Secondly, we assessed response to clopidogrel in naive patients with T2DM and stable CAD in a randomised controlled trial. Thrombus area was measured by Badimon chamber and platelet reactivity by VerifyNow®. In T2DM patients presenting with NSTE-ACS, thrombus area was greater compared to non-diabetic patients (mean ± SD, 20,512 ± 12,567 [n=40] vs. 14,769 ± 8,531 [n=40] μm²/mm, p=0.02) Clopidogrel decreased thrombus area among stable CAD patients with T2DM (mean ± SD, Clopidogrel [n=45]: 13,978 ± 5,502 to 11,192 ± 3,764 μm²/mm vs. placebo [n=45]: 13,959 ± 7,038 to 14,201 ± 6,780 μm²/mm, p<0.001, delta values: clopidogrel vs. placebo, mean ± SD, 2,786 ± 4,561 vs. -249 ± 2,478, p<0.0005). Only 44% of patients with CAD and T2DM responded to clopidogrel as per VerifyNow® (cut-off PRUz value of ≥ 240). Importantly, no correlation was observed between thrombus area and VerifyNow® values (rho 0.08, p=0.49). Thrombus area values were similar among hypo-responders and good responders to clopidogrel (mean thrombus area ± SD: 12,186 ± 4,294 vs. 10,438 ± 3,401; p=0.17). Type 2 diabetes mellitus is associated with an increased blood thrombogenicity among NSTE-ACS patients on currently recommended medical therapy. Thrombus area was significantly reduced in all stable CAD patients independently of their response to clopidogrel therapy.