[Effects of angiotensin converting enzyme inhibitor with different doses on plasma brain natriuretic peptide and norepinephrine in patients with chronic heart failure].

OBJECTIVE: To investigate the effects of angiotensin converting enzyme inhibitor (ACEI) with different doses on the plasma brain natriuretic peptide and norepinephrine (NE) of patients with chronic heart failure and the feasibility and safety of high dose ACEI treatment. METHODS: Sixty-six patients with chronic heart failure were randomly divided into 2 groups: low-dose group, treated by perindopril with the dosage of 2 mg/d initially and gradually increased up to 2-4 mg/d, and high-dose group, treated by perindopril with the dosage of 2 mg/d initially and gradually increased up to 8 approximately 10 mg/d. Treatment lasted for 12 weeks. Before and after the treatment peripheral blood was collected to test the plasma NE and brain natriuretic peptide levels, and the left ventricular ejection fraction (LVEF), left ventricular end diameter (LVED), blood pressure, and heart rate were examined. The differences of these indexes between the two groups and within the same group before and after the 12-week treatment were analyzed. Thirty healthy subjects were used as control group. RESULTS: The levels of plasma brain natriuretic peptide and NE of the chronic heart failure patients were significantly higher than those of the normal controls, and the higher the NYHA class of heart failure the higher the plasma levels of NE and brain natriuretic peptide. The plasma brain natriuretic peptide level was negatively correlated with LVEF (r = -0.327, P = 0.012) and positively correlated with plasma NE level (r = 0.402, P = 0.002) and LVED (r = 0.42, P = 0.015). The plasma brain natriuretic peptide and NE levels in the high-dose group were 6 microg/L +/- 4 microg/L and 250 ng/L +/- 63 ng/L respectively, both significantly lower than those of the low-dose group (8 microg/L +/- 4 microg/L and 387 ng/L +/- 211 ng/L respectively, both P < 0.05). Most of the patients in these 2 groups tolerated well. CONCLUSION: Plasma brain natriuretic peptide level is negatively correlated with the severity of heart failure and positively correlated with plasma NE. Treatment of CHF by perindopril with gradually increasing dose obviously decreases the plasma brain natriuretic peptide and NE levels and is tolerable for the patients.