Hemodynamic, renal, and hormonal effects of adrenomedullin infusion in patients with congestive heart failure

Abstract

Background - Experimental studies have shown that adrenomedullin (AM) causes vasodilatation, diuresis, and a positive inotropic effect. In humans, however, whether infusion of AM has beneficial effects in congestive heart failure (CHF) remains unknown. Methods and Results - Hemodynamic, renal, and hormonal responses to intravenous infusion of human AM (0.05 μg · kg-1 · min-1) were examined in 7 patients with CHF and 7 normal healthy subjects (NL). In NL group, AM significantly decreased mean arterial pressure (-16 mm Hg, P<0.05) and increased heart rate (+12 bpm, P<0.05). In CHF group, AM also decreased mean arterial pressure (-8 mm Hg, P<0.05) and increased heart rate (+5 bpm, P<0.05), but to a much lesser degree (P<0.05 versus NL). AM markedly increased cardiac index (CHF, +49%; NL, +39%, P<0.05) while decreasing pulmonary capillary wedge pressure (CHF, -4 mm Hg; NL, -2 mm Hg, P<0.05). AM significantly decreased mean pulmonary arterial pressure only in CHF (-4 mm Hg, P<0.05). AM increased urine volume (CHF, +48%; NL, +62%, P<0.05) and urinary sodium excretion (CHF, +42%; NL, +75%, P<0.05). Only in CHF, plasma aldosterone significantly decreased during (-28%, P<0.05) and after (-36%, P<0.05) AM infusion. These parameters remained unchanged in 7 patients with CHF and 6 healthy subjects who received placebo. Conclusions - Intravenous infusion of AM has beneficial hemodynamic and renal effects in patients with CHF.