RESUMEN
OBJECTIVE: To detect plasma brain natriuretic peptide (BNP) changes in hemodialysis patients with chronic renal failure (CRF) and assess the diagnostic value of BNP for cardiac function. METHODS: Plasma BNP concentration was measured in 93 hemodialysis patients with CRF and 52 healthy control subjects. In the 93 patients, echocardiographic examinations were performed to determine the relationship between BNP and cardiac function. RESULTS: The median plasma BNP levels in 52 normal controls were 3.35 pg/ml (1.00-9.73 pg/ml), and 146.5 pg/ml (56.2-546.9 pg/ml) and 90.0 pg/ml (18.3-310.5 pg/ml) in 93 patients before and after hemodialysis, respectively, showing significant difference among those 3 groups (P<0.001). The plasma BNP levels in patients with CRF complicated by heart failure (LVEF<50%) before and after hemodialysis were 686.0 pg/ml (334.5-1319.3 pg/ml) and 248.0 pg/ml (80.3-814.5 pg/ml) respectively, significantly higher than 62.8 pg/ml (22.0-321.6 pg/ml) and 20.7 pg/ml (1.0-200.9 pg/ml) in patients with normal cardiac function (LVEF > or = 50%) (P=0.002). The plasma BNP levels in patients with dilated left ventricle before and after hemodialysis were 609.0 pg/ml (254-1152.0 pg/ml) and 310.0 pg/ml (28.3-839.6 pg/ml) respectively, significantly higher than 62.8 pg/ml (23.2-192.5 pg/ml) and 22.4 pg/ml (1.0-80.7 pg/ml) in patients with normal left ventricle. Multiple linear regression analysis for left ventricular diastolic dimension, LVEF and plasma BNP level before hemodialysis showed that high BNP level was significantly correlated with dilated left ventricle and poor cardiac function (P<0.01). CONCLUSIONS: Plasma BNP levels in hemodialysis patients with CRF are significantly higher than those in healthy controls, and are significantly lowered after hemodialysis but still remain higher than the normal level. Plasma BNP levels in hemodialysis patients with dilated left ventricle or heart failure are significantly higher than those in patients with normal left ventricle or cardiac function, and high plasma BNP level is significantly correlated with dilated left ventricle and poor cardiac function.