[New pathogenic findings on the mechanism of heart failure and their importance in therapy]

Activation of the neuroendocrine system participates in a decisive way in the pathogenesis of cardiac insufficiency. The authors draw attention to the basic therapeutic impact of the phenomenon of so-called "down-regulation" of myocardial beta-adrenoreceptors which takes place during chronic cardiac insufficiency, contrary to acute cardiac failure. The authors deal from the pathogenetic aspect with different groups of positive inotropic substances used in the treatment of cardiac insufficiency with special attention to digoxin and cardiac glycosides. They evaluate the effect of digoxin as a neurohumoral modulator in acute and chronic cardiac insufficiency. Its potential asset is the positive modulation of excessive neuroendocrine activation and the favourable effect on cardiopulmonary baroreflexes. The authors explain also why at present among positive inotropic substances in the treatment of cardiac insufficiency only cardiac glycosides are indicated. They mention the theoretical possibility to extend the indication of digoxin to retard the progressive deterioration of cardiac function in asymptomatic dysfunction of the left ventricle caused by the neurohumoral modulating effect of digoxin.