Dyscoagulable state have been seen in patients with severe and end-stage heart failure (ESHF). Elevated levels of platelet activation markers are followed by high incidence of thromboembolic complication (TEC) in patients with sinus rhythm as well as atrial fibrillation. Surface morphology and elasticity of platelets play significant role in thrombus formation and can be investigate by atomic force microscopy (AFM).Aim
Local elastic properties (LEP) of platelets were investigated by AFM in patients with ischemic ESHF, whom were selected for emergency open heart surgery.Aim
Cohort of study includes ESHF patients (4 male, mean age is 52,4 years, preoperative LVEF 16,1 ± 3,1%) with left ventricular assist device (VAD). Blood sample volumes were taken before surgery, after bypass starting and three times after VAD implantation in warfarine treated pts. At 6 month one patient had TEC in left vena reticularis bed with deficit of lateral view field.Aim
AFM images were captured in air using contact mode with commercially available silicon cantilevers CSC38 ("MikroMasch" Co., Estonia, spring constant of 0.03 N/m). Platelet LEP were quantitatively determined on the basis of force spectroscopy. The force curves have been fitted with the Hertz model to obtain elastic modulus (Young's modulus) values of resting platelets. Coagulogramm and spontaneous and stimulated platelets aggregations were assessed.Results
Patient with thromboembolic event had significantly higher Young's modulus than the patients without TEC (as shown in the table).Conclusions
High Young's modulus value indicates the platelet fragility in patients with ESHF. VAD implantation followed by attenuation of platelet cytoskeleton dysfunction with decreasing of elastisity. Dramatically increased Young's modulus in patient with TEC proves multifactor nature of hypercoagulation in ESHF patients with artificial heart ventricles.