[Rheological determinants of end-organ damage]

Various studies demonstrated an interdependence between rheological parameters and advanced stages not only of ischaemic heart disease and peripheral arterial occlusive disease, but also of chronic obstructive lung disease. In ischaemic heart disease, rheological alterations in the poststenotic circulation can result in impairment of the oxygen supply of the myocardium. Rheological therapies aim for a reduction in plasma viscosity and improved microcirculatory flow by means of a reduction of the elevated levels of fibrinogen. As an example, intermittent therapy with urokinase has been established as a treatment of refractory angina pectoris. Treatment with fibrates also can result in an improvement of microcirculation due to reduced hepatic fibrinogen synthesis. Treatment with statins leads to an improvement of microcirculation due to effects on serum lipids. In patients with chronic obstructive lung disease and cor pulmonale who, secondary to chronic hypoxia, develop polycythaemia and disturbances in pulmonary microcirculation, isovolumic haemodilution may result in a reduction of pulmonary arterial pressure with consecutively increased cardiac output and improved exercise capacity.