Comparison Of B-type Natriuretic Peptide (BNP) In Left Or Right Ventricular Dysfunction And Relationship Between BNP And Short-term Cardiac Death In Serious Heart Failure

Objective: To investigate the concentration of B-type Natriuretic Peptide(BNP) in patients with heart failure and compare BNP level in patients with left or right ventricular dysfunction. The relationship between BNP levels and short-term cardiac death in patients with serious heart failure was also studied.Methods: Part One: Thirty-five patients presenting with dyspnea were included in the study. The patients were divided into 4 groups: the left ventricular systolic dysfunction group (10 patients were diagnosed as primary hypertension with LVEDD>50mm, EF<45%); the left ventricular diastolic dysfunction group (10 patients were diagnosed as primary hypertension with LVEDD<50mm, EF>50%, E/A<1); the right ventricular dysfunction group (10 patients were diagnosed as chronic pulmonary heart disease) and the control group (5 patients were diagnosed as cardiovascular neurosis). All the patients underwent BNP assay. Part Two: Twenty-eight patients with NYHA class IV were enrolled in the study. All the patients underwent theconventional therapy and BNP assay, the cardiac death in the following two weeks was recorded and BNP levels between the dead and survivors were compared.Results: 1. In the left ventricular systolic dysfunction group, the concentration of BNP was much higher than that of control group (1903.04 + 1829.22pg/ml vs 55.16 46.55pg/ml). There were significant differences of BNP levels among NYHA II, III and IV(class II :493.43 140.65 pg/ml, class III :1669.90 1373.07 pg/ml, class IV :4015.67 1546.58 pg/ml, p=0.013). The concentration of BNP had a negative correlation with LVEF(r=-0.812). 2. In the left ventricular diastolic dysfunction group , the concentration of BNP was higher than that of control group(364. 28 + 226. 18pg/ml vs 55.16?6.55pg/ml). 3. To compare BNP levels among the four groups, the concentration of BNP was highest in the left ventricular systolic dysfunction group (1903.04 1829.22pg/ml) , medium in the left ventricular diastolic dysfunction group (364.28 226.18pg/ml), lowest in the right ventricular dysfunction group (199.46 155.88pg/ml) , all these three groups showed higher concentration than those in the control group (55.16 46.55pg/ml) (p<0.001). 4.BNP levels of the dead and the survivors had significant difference , the concentration of BNP in dead patients increased significantly than that of survivors ( 20776.50 13530.98 pg/ml vs4033.37 2621.98pg/ml,p<0.01) .Conclusion:1. The concentration of BNP in patients with left ventricular systolic dysfunction is much higher than that in healthy subjects. BNP has a positive correlation with NYHA classification and a negative correlation with LVEF. 2. The concentration of BNP in patients with leftventricular diastolic dysfunction is higher than that in healthy subjects, but lower than that in left ventricular systolic dysfunction.3.The BNP levels differ greatly between the left and the right ventricular dysfunction and the concentration of BNP is useful in distinction of dyspnea caused by cardiac or pulmonary disease. 4.There is a significant correlation between BNP and short-term cardiac death in patients with NYHA classIV,the risk of cardiac death increase significantly when BNP levels are greatly elevated.