The study will be a pathophysiological, single-centre, observational study, in which all 4 groups, including the parallel-group will be investigated in terms of qualitative-, echocardiographic-, arterial resistance, exercise testing (CPEX and 6-MWT), endothelial dysfunction assessment by Laser Doppler and vascular biomarker measurements. We intend to investigate if there is increasing arterial resistance from group "A" to group "D" and a significant difference in arterial resistance between groups "D" and "E" by measuring the PWV.