CARDIAC SECRETION OF ATRIAL AND BRAIN NATRIURETIC PEPTIDES IN ACUTE ISCHEMIC HEART-FAILURE IN PIGS - EFFECT OF ANGIOTENSIN-II RECEPTOR ANTAGONISM

In a model of acute ischaemic left ventricular failure in pigs, we com pared the plasma levels and cardiac secretion of the three atrial pept ides, atrial natriuretic factor (ANF), N-terminal proatrial natriureti c factor (N-terminal proANF) and brain natriuretic peptide (BNP). Acut e ischaemic left ventricular failure was induced by embolization of th e left coronary artery with plastic microspheres. Thereafter, treatmen t was given by an intravenous injection of the angiotensin II receptor (AT1) antagonist losartan. Effects of failure induction and treatment were documented by measurement of haemodynamic parameters and plasma concentrations of catecholamines, plasma renin activity, angiotensin I I and aldosterone. Acute left ventricular failure was accompanied by s ignificant increases in cardiac secretion and plasma levels of all thr ee atrial peptides, which was considerably more pronounced for ANF and N-terminal proANF than for BNP. Treatment with losartan resulted in s ignificant decreases in plasma ANF and N-terminal proANF, whereas BNP did not change. These findings indicate that ANF and N-terminal proANF may be better suited than BNP as markers of cardiac preload during th e development and treatment of acute heart failure.