Abstract

Objective Natriuretic peptides have actions likely to ameliorate cardiac dysfunction. BNP is indicated as treatment for decompensated cardiac failure but its utility in the context of acute myocardial infarction is unknown.

Design Double-blinded randomized placebo-controlled trial.

Setting Tertiary hospital coronary care unit. Patients: 28 patients with acute myocardial infarction with delayed or failed reperfusion and moderate left ventricular dysfunction.

Interventions Infusion of BNP or placebo for 60 hours post MI.

Main Outcome Measures Neurohormonal activation and renal function in response to BNP infusion, secondary endpoints of echocardiographic measures of LV function and dimension.

Results BNP infusion resulted in significant elevation of BNP( 276 pg/L vs. 86 pg/L, P=0.001). NT-proBNP levels were suppressed by BNP infusion (p=0.002). ANP and NT-proANP levels fell with a significant difference in the pattern between BNP infusion and placebo during the first 5 days (p<0.005). CNP and NCNP levels rose during the infusion with higher levels than placebo at all measures during the first 3 days (p<.01). cGMP was elevated during the infusion period with a peak at 23pmol/L on day 2 (placebo 8.9 pmol/L, p=0.002), with a correlation between BNP and cGMP levels (p<0.001). GFR fell in BNP infusion but was not significantly lower than placebo (71.0 ± 5.6 vs. 75.8 ± 5.4 mls/min/1.73m2, p=0.62). Patients receiving Nesiritide exhibited favorable trends in left ventricular remodeling.

Conclusions Given early post-MI, Nesiritide induced increments in plasma cGMP and CNP and decrements in other endogenous cardiac peptides with a neutral effect on renal function and trends towards favorable ventricular remodeling.