RESUMO
Aim To study platelet adhesion mediated by von Willebrand factor (VWF) in patients with premature ischemic heart disease (IHD).Material and methods This study enrolled 58 patients with stable IHD, including 45 men younger than 55 years with the first manifestation of IHD at the age of <50 years and 13 women younger than 65 years with the first manifestation of IHD at the age of <60 years. The control group consisted of 33 patients, 13 men younger than 55 years and 20 women younger than 65 years without IHD. Platelet adhesion to the collagen surface at the shear rate of 1300 s-1 was studied by evaluating the intensity of scattered laser light from the collagen-coated optical substrate in a flow chamber of a microfluidic device after 15-min circulation of whole blood in the chamber. Decreases in platelet adhesion after addition to the blood of monoclonal antibodies (mAb) to platelet receptors glycoproteins Ib (GPIb) to inhibit the receptor interaction with VWF were compared for patients of both groups. Results In patients with premature IHD, the decrease in platelet adhesion following the platelet GPIb receptor inhibition was significantly less than in patients of the control group (74.8â% (55.6; 82.7) vs. 28.9â% (-9.8; 50,5), p <0.001). For the entire sample, the median decrease in platelet adhesion following the GPIb receptor inhibition was 62.8â% (52.2; 71.2). With an adjustment for traditional risk factors of IHD, a decrease in platelet adhesion of >62.8% after blocking GPIb receptors increased the likelihood of premature IHD (OR=9.84, 95â% CI: 2.80-34.59; p <0.001).Conclusion Blocking the interaction of GPIb receptors with VWF in patients with premature IHD and increased shear rate induced a greater decrease in platelet adhesion than in patients without this disease. This suggested that an excessive interaction of VWF with platelets might contribute to the pathogenesis of premature IHD.
