Changes and clinical significance of serum brain natriuretic peptide le vels in patients with chronic heart failure

AIM: To investigate the changes and clinical sig ni ficance of serum brain natriuretic peptide (BNP) levels in patients with chronic heart failure. METHODS: ELISA method was used to measure the se rum levels of BNP-32 in 72 patients with chronic heart failure (HF group) and 3 0 healthy subjects served as control group. 46 patients with New York Heart Asso ciation (NYHA) class Ⅲ and class Ⅳ were measured repeatly after 2-weeks treat ment. The differences between BNP levels and different NYHA classes or underlyin g diseases were analysed. The changes of BNP levels before and after treatment i n the same patients were also compared. RESULTS: (1) The serum l evels of BNP in HF group and control group were 858.7 ± 326.9 and 109.3 ± 37.6 ng·L -1 , and the 95% confidence interval of both group were 781.9 - 935.5 and 95.3 - 123.3 ng·L -1 , respectively (P 0.01 ). (2) The sensitivity and specificity of BNP cut-off valu e of 120 ng·L -1 for diagnosing chronic heart failure were 100% and 8 7%. (3) BNP levels in NYHA classⅡ, Ⅲ and Ⅳ were 638.5 ± 224.5 , 878.0 ± 334.0 and 1045.8 ± 585.1 ng·L -1 , respectively (P 0.01 ). The levels of BNP increased markedly with NYHA class highte ning (r= 0.818 , P 0.01 ). CONCLUSION: The levels of BNP are significantly increased, and correlated with the NYHA class, a s well as with prognosis in patients with HF. After treatment, falling BNP level s in patients show good outcomes, whereas elevating BNP levels in patients show bad outcomes. The level of BNP has important value in diagnosis, therapentic eff icacy and prognosis of patients with chronic heart failure.