Venous blood will be sampled three times (before and after rehabilitation and maximal stress test) for the assessment of platelet activation by flow cytometer and hemorheological profile by coagulation analyzer. Mean platelet volume, and platelet activation markers (platelet-bound CD62P%G, CD63%G, CD40L%G) will be analyzed. Various coagulation and fibrinolysis factors will be quantified including PT, aPTT, fibrinogen, thrombin time, FVIII:C, antithrombin, plasminogen, antiplasmin, anti-Xa and thrombin generation, D-Dimer, vWF etc.