Summary
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.
Keywords
Type 2 diabetes mellitus - acute coronary syndrome - stable coronary artery disease
- thrombus - antiplatelet therapy