[Molecular pathobiology in heart failure].

Heart failure is a pathophysiological state resulting from disturbed cardiac function. It is based on complex molecular processes, many of which are not fully understood. During heart failure adaptive mechanisms, that reinstall altered cardiac function, are activated. The main mechanisms are: a) Alteration of the structure and composition of myocytes by myocardial hypertrophy, reexpression of fetal and neo-natal proteins and the expression of certain proto-oncogenes; b) Activation of the neuroendocrinal system, specifically the sympathetic nervous system, renin-angiotensin-aldosterone system and vasopressin release; c) Activation of autocrine and paracrine systems. However, when these systems are activated beyond a certain limit they contribute to heart failure aggravation. This can also be promoted by alteration of the calcium metabolism inherent in heart failure. The synthesis of the counterregulator atrial natriuretic factor is also increased.