NT-脑钠肽在左心功能不全诊断中的价值

目的探讨N末端脑钠肽(NT-BNP)在心功能不全诊断中的价值。方法对81例NYHAⅠ、Ⅱ、Ⅲ、Ⅳ级器质性心脏病患者,在入院治疗前抽肘静脉血,用酶免疫测定法测定NT-BNP;正常人36例为对照组,在体检时抽血检测NT-BNP。抽血当天超声心动图评估心功能不全时的相关指标,左室射血分数(LVEF)、左室舒张末径以及肺动脉压。结果对照组、Ⅰ、Ⅱ、Ⅲ、Ⅳ级器质性心脏病患者NT-BNP中位数依次为26.6、70、151.2、2724.1、7728.7pg/ml,NT-BNP对数均值为(1.5±0.4)、(2±0.4)、(2.3±0.5)、(3.3±0.6)、(3.8±0.5),单因数方差分析差异有显著性(P<0.01),若以256pg/ml为诊断左心衰临界值,其敏感性为97%,特异性为85%。NT-BNP与NYHA分级心脏功能指标的相关系数为(r=0.456,P<0.01)。诊断左心功能不全NT-BNP比心脏彩超有更高的敏感性和特异性。结论NT-BNP是诊断左心衰竭快速、简便、敏感、特异的指标,也可用于判断左心衰竭严重程度。NT-BNP与肺动脉压有相互关系,测定NT-BNP并通过临床分析可为正确诊断心肺疾病提供有价值的信息。

Clinical value of N-terminal proBNP in diagnosis of left heart failure

Objective To evaluate the clinical value of N - terminal proBNP （NT- BNP） in diagnosis of left heart failure. Methods According to NYHA classification, 81 patients with heart disease were divided into four groups, 15, 26, 22 and 18 cases in grades Ⅰ, Ⅱ, Ⅲ and Ⅳ, respectively. 36 healthy individuals were selected as control group. NT- proBNP was detected using enzyme- immunoassay method in all subjects. Meanwhile, correlated heart failure indexes such as left ventricular ejection fraction （LVEF）, left ventricular diastolic end diameter （LVDD） and pulmonary arterial pressure were determined by echocardiograph Results The median NT- BNP in control group, patients with NYHA grades Ⅰ, Ⅱ, Ⅲ and Ⅳ were 26.6, 70, 151.2, 2724.1, and 7728.7 pg/ml, and their logarithmic transformation were （1.5±0.4）, （2 ±0.4）, （2.3±0.5）, （3.3 ±0.6） and （3.8 ± 0.5）, there was statistical significant difference （ P 〈0.01）. 256pg/ml was the best critical point for diagnosing heart failure with 97% sensitivity and 85% specificity. The correlation coefficient of NT-proBNP with NYHA functional classification was （ r = 0. 456, P 〈0.01）. NT-BNP has better sensitivity and specificity than color Doppler ultrasonography in diagnosing left heart failure Conclusion NT- BNP is a quick, convenient, sensitive and specific marker in diagnosis of left heart failure. NT- BNP is also a good objective index in evaluation of severity of left heart function. NT-proNP concentrations and pulmonary arterial pressure have linear correlation each other, which can help analysing disease condition.