The Value Of Plasma N-terminal Pro-brain Natriuretic Peptide Levels In Diagnosing And Differentiating In Patients Presenting With Acute Dyspnea

OBJECTIVETo investigate the clinical value of the plasma N-terminal pro-brain natriuretic peptide levels in patients with acute cardiac dyspnea or noncardiac dyspnea.METHOD93 patients with acute dyspnea were divided into two groups: cardiac dyspnea group (61 cases) and noncardiac dyspnea group (32 cases). In cardiac dyspnea group, according to the results of echocardiography, the cases were divided into three groups: pure diastolic heart failure (25 cases), pure systolic heart failure (21 cases) as well as diastolic and systolic heart failure (15 cases). At the same time, according to New York Heart Association (NYHA), heart function was classified into gradeⅡ20 cases, gradeⅢ23 cases and gradeⅣ18 cases. The plasma NT-proBNP level (concentration) was measured by enzyme-linked immunosorbent assay (ELISA). The data was analyzed by SPSS13.0.RESULTSThe plasma NT-proBNP level of the cases with cardiac dyspnea and noncardiac dyspnea was 3641.48±2931.53ng/L and 565.83±301.53ng/L respectively. There was a significant difference between cardiac dyspnea cases and noncardiac dyspnea cases (P＜0.01) If 600ng/L was taken as a critical value, the plasma NT-proBNP level was excellently sensitive for diagnosing cardiac dyspnea (95.08%) , but the specificity was not very good (68.72%) . In cardiac dyspnea group, the plasma NT-proBNP level in the cases with pure diastolic heart failure, pure systolic heart failure, as well as diastolic and systolic heart failure was 2251.09±1308.90ng/L, 3736.31±2590.26ng/L, and 5804.80±4166.47ng/L respectively. A significant difference was found in three groups (P＜0.05～0.01) The plasma NT-proBNP level in the cases with different class of the NYHA heart function was also significantly different (P＜0.01) , and the worse heart function was, the higher plasma NT-proBNP level was. In addition, a moderate inverse correlation occurred between the plasma NT-proBNP level and LVEF in cases with cardiac dyspnea (r=-0.599, P＜0.01) , but no relation with LVEDd (r=0.222, P＜0.05 )CONCLUSIONThe plasma NT-proBNP level is highly sensitive for diagnosing cardiac dyspnea and differentiating with noncardiac dyspnea, and has an important role in clinic. The plasma NT-proBNP level in the patients with systolic heart failure is higher than the one of the patients with diastolic heart failure. The worse classification of NYHA heart function is, the higher plasma NT-proBNP level is. However, because the plasma NT-proBNP level in the individuals with different types of heart failure and in the different classification of heart function has a great overlap, the function as a guideline for typing heart failure or ranking heart function is limited.