Intravenous atrial natriuretic peptide prevents left ventricular remodeling in patients with first anterior acute myocardial infarction

OBJECTIVES The study evaluates the effect of atrial natriuretic peptide (ANP) compared with nitroglycerin (GTN) on left ventricular (LV) remodeling after first anterior acute myocardial infarction (AMI). BACKGROUND Compared with GTN, ANP suppresses the renin-angiotensin-aldosterone system and endothelin-1 (ET-1), which stimulate LV remodeling. METHODS Sixty patients with a first anterior AMI were randomly divided into the ANP (n = 30) or GTN (n = 30) groups after direct percutaneous transluminal coronary angioplasty. We evaluated LV ejection fraction (LVEF), end-diastolic volume index (LVEDVI) and end-systolic volume index (LVESVI) at the acute phase and after one month. We also measured neurohumoral factors during study drug infusion. RESULTS There was no difference in the baseline characteristics or LVEF (46.9 ± 1.0 vs. 46.8 ± 1.3%) between the two groups. Although there was no difference in hemodynamics during the infusion periods, the LVEF was significantly improved after one month compared with the baseline value in both groups, but it was improved more in the ANP group than in the GTN group (54.6 ± 1.1%, 50.8 ± 1.3%, p < 0.05). Left ventricular enlargement was prevented in the ANP group (LVEDVI, 85.8 ± 3.1 ml/m2 to 87.3 ± 2.7 ml/m2; P = ns, LVESVI, 45.6 ± 1.8 ml/m2 to 41.0 ± 2.1 ml/m2, p < 0.05) but not in the GTN group (LVEDVI, 86.2 ± 4.1 to 100.2 ± 3.7, p < 0.01; LVESVI, 46.3 ± 2.8 ml/m2 to 51.1 ± 3.0 ml/m2, P = ns). During the infusion, ANP suppressed plasma levels of aldosterone, angiotensin II and ET-1 compared with GTN. CONCLUSIONS These findings indicate that in patients with a first anterior AMI, an ANP infusion can prevent LV remodeling better than can GTN, and effectively suppresses aldosterone, angiotensin II and ET-1.