N末端B型利钠肽原对主动脉瓣狭窄患者诊断价值

目的 评价N末端B型利钠肽原(NT-proBNP)对主动脉瓣狭窄(AS)患者的诊断价值,分析NT-proBNP与美国纽约心脏协会(NYHA)心功能分级和超声心动图所测指标的相关性.方法 2005年5月至2006年7月因AS住院患者,使用酶联免疫的方法对40例AS患者(AS组)和76名健康对照者(正常组)行NT-proBNP测定.评价NT-proBNP对AS的诊断价值,及其与临床心功能分级、超声心动图指标的相关性.结果 AS组的NT-proBNP水平比正常组显著高(P＜0.01);在NYHA心功能Ⅱ、Ⅲ和Ⅳ级者呈逐级显著高(均P＜0.01),轻中度狭窄组高3.5倍(2.95±0.48)ng/L比(2.63±0.10)ng/L,P＜0.05],重度狭窄组高6倍(3.16±0.50)ng/L,P＜0.01);伴随左室质量指数(LVMI)也显著高于正常组,且在轻、中度狭窄组高1.7倍(169±51)比(100±22),P＜0.01],重度狭窄组高2.1倍(212±86)ng/L比(100±22)ng/L,P＜0.01].当NT-proBNP阈值在1150 ng/L和1356 ng/L时,分别是诊断轻、中度(AUC=0.657,P＜0.05)及重度AS(AUC=0.848,P＜0.01)的最佳阈值;诊断的敏感性、特异性和准确性分别为61.11%和77.30%,69.74%和96.10%以及68.09%和91.80%.单因素分析,Log(NT-proBNP)与左室舒张期末内径(LVEDD)、LVMI和平均主动脉瓣跨瓣压差(MTPG)均呈显著正相关(r=0.325,均P＜0.05),而与左室射血分数(LVEF)呈负相关(r=-0.487,P=0.01);多元逐步回归分析不仅与NYHA分级和LVEF,而且Log(MTPG)与NT-proBNP独立相关(P＜0.05).结论 NT-proBNP对AS患者有诊断价值,不仅与心功能相关,还与AS的严重程度相关.

Clinical value of NT-proBNP in the diagnosis and analysis of correlation of NT-proBNP with clinical and echocardiographic findings in patients with aortic stenosis

Objective To evaluate the diagnostic value of NT-proBNP in patients with aortic stenosis (AS) , analyze the relation of NT-proBNP to NYHA functional class and echocardiographic findings. Methods Measured the whole venous blood of NT-proBNP with enzyme linked immuno sorbent assay in 40 aortic stenosis patients ( AS group) and 76 normal subjects ( control group). We assessed the diagnostic value of NT-proBNP for aortic stenosis, and related NT-proBNP to clinical NYHA functional class and echocardiographic findings. Results Compared to controls, NT-proBNP levels had significantly higher in patients with aortic stenosis ( P ＜ 0. 01 ). The level of NT-proBNP was gradually and significantly increased with the NYHA functional Ⅱ , Ⅲ and Ⅳclass compared to controls (all P ＜0. 01 ). NT-proBNP was significantly (3.5 times) higher in mild/moderate stenosis group than that in control group(2. 95 ± 0. 48 vs 2.63 ±0. 10, P ＜0. 05), and was significantly (6.0 times) higher in severe stenosis group than that in control group(3.16 ±0. 50 vs 2. 63 ±0. 10,P ＜0. 01 ). LVMI was significantly ( 1.7 times) higher in mild/moderate stenosis group than that in control group( 169 ±51 vs 100 ±22, P ＜0. 01 ), and was significantly (2.1 times) higher in severe stenosis group than that in control group(212 ± 86 vs 100 ± 22, P ＜ 0. 01 ).The NT-proBNP values of 1150 ng/L and 1356 ng/L were determined as the best cutoff values for the diagnosis of patients with mild/moderate ( AUC = 0. 657, P ＜ 0. 05 ) and severe aortic stenosis ( AUC = 0. 848,P ＜0. 01 ), the sensitivity, specificity and accuracy were 61.11% and 77. 30% ,69.74% and 96. 10%,68.09% and 91.80%. Log(NT-proBNP) was significantly positively related with LVEDD, LVMI and mean transvalvular pressure gradient(MTPG) ( all P ＜ 0. 05 ), and negatively related with LVEF ( P = 0. 01 ) in univariate analysis. In multiple regression analyses, NYHA functional class, LVEF and Log(MTPG) was independently associated with NT-proBNP. Conclusion NT-proBNP is valuable for the diagnosis of patients with aortic stenosis. NT-proBNP has correlation with the heart function and severity of the aortic stenosis.