Aim of this study was to evaluate the relationships between VWF antigen (VWF:Ag) levels, collagen binding activity of VWF (VWF:CB), ADAMTS-13 and interleukin-6 (IL-6) levels in affecting platelet response to dual antiplatelet treatment.
In 159 acute coronary syndrome (ACS) patients undergoing percutaneous coronary interventions we measured platelet function by platelet aggregation with two agonists [1 mM arachidonic acid (AA) and 10 μM ADP]. We defined patients with RPR those with platelet aggregation by AA > 20 % and/or ADP (10 µmol) > 70 % .
We found significantly lower ADAMTS-13 activity, elevated IL-6, VWF:Ag and VWF:CB levels in patients with RPR. A lower ADAMTS-13 activity was present in patients with VWF:Ag and VWF:CB in the upper tertile. At the multivariate analysis ADAMTS-13 activity and IL-6 were independent risk factors for RPR.
Our results indicate that ADAMTS-13 activity and IL-6 levels independently affect RPR and suggest that, by different pathways, both are involved in the variable response to antiplatelet therapy.