Value Of Brain Natriuretic Peptide In Assessment Of Patients With Heart Failure

Objective: Congestive heart failure (CHF) is a syndrome which resulted from various kinds of cardiac diseases such as congenital cardiovascular disease, coronary atherosclerotic heart disease and valvular heart disease. There is a series neuroendocrine abnormality in the people with congestive heart failure, which involves more excretion of brain natriuretic peptide. BNP is important in the procession of occurrence and progress of congestive heart failure, which has been proved to be a simple method for the diagnosis of CHF. But currently, UCG is still a main method to evaluate the extent of CHF, as well as symptoms. Though convenient they are, their accuracy is affected by many subjective factors. For example, LVEF as an important index of UCG is affected much by the existence of valvular heart disease and Diastolic dysfunction. Our research aims at testing the concentration of plasma BNP in two groups, normal people and patients with different extent of CHF, and comparing BNP levels with variables of clinical and ultrasound- cardiography in order to probe its correlation with NYHA cardiac function classification and certain its value in the diagnosis of congestive heart failure.Methods: From 2002.12 to 2003.7, 150 persons were studied, including 86 patients with congestive heart failure certained by NYHA cardiac function classification and 64 normal subjects composed of 34 male and 30 female. The participants were free of renal dysfunction (Cre>176.8μmol/l). Patients with CHF were grouped into four parts by NYHA-class and LVEF, respectively. All subjects with check of chest radiography, meanwhile underwent common ECG and standard M-mode and two dimensional UCG. Left ventricular ejection fraction(LVEF), Left Ventricular End-Diastolic Volume (LVEDV), Left Ventricular End-systolic Volume (LVESV), Left Ventricular Internal Dimension(LVID), Ventricular Septal Thickness (VST),Posterior Wall Thickness (PWT), Left Ventricular Mass(LVM) were measured at end of diastole, left ventricular mass was determined by using Devereux formula. BNP was measured by ELISA method. Blood creatinine concentration obtained from routine laboratory method. All data was tested with SPSS11.5 software. Numercial variable data were expressed mean±stand deviation (±S), independent-samples T Test was used. Categorical variable data were assessed by analysis of variance. Relation between BNP and variable of clinical or UCG was evaluated by linear analysis. Spearman's rank correlation analysis was performed to establish BNP related to the NYHA-class. A p value<0.05 was considered statistically significant.Results: 150 subjects consists of 86 patients(44 male,34 female) with a diagnosis of CHF by NYHA cardiac function classification and 64 normal control(34 male, 30 female). The highest BNP concentration (10.06±4.71ng/ml) was obsolete myocardial infarction patients. The BNP level of NYHA Ⅰ～Ⅳ were 1.34±0.63ng/ml , 3.66±2.24ng/ml , 7.22±2.46ng/ml, 9.89±3.14 ng/ml, respectively, which shows the trend of increasing. BNP level of NYHAⅠ～Ⅳ group higher than that of normal control group (P <0.05). BNP level of NYHAⅡ～Ⅳ group higher than that of NYHAⅠgroup(P <0.05). The BNP level of LVEF>5%, 45%-55%,35%～45%,<35% were respectively 2.62±1.56ng/ ml,1.79±0.74ng/ml,5.30±2.86ng /ml,13.46±8.95ng/ml. The BNP level of LVEF 35%～45% group higher than that of LVEF>45% group (P<0.05). The BNP level of LVEF<35% group was higher than that of LVEF35%～45% group (P<0.05). There were some correlation between most of echocardiographic or clinical parameters and BNP. There were significant positive correlations between BNP and NYHA-class, serum creatinine concentration, heart chest ratio, The correlation coefficient were respectively 0.39, 0.37, 0.29,(P<0.05). There were non-significant correlation were seen with the age (P>0.05), heart rate (P>0.05). Of the echocardiographic variables analyzed, BNP correlated positively with the left ventricular diameter and left ventricular mass, and inversely with the left ventricular...