Parthenakis Frangiskos I, Patrianakos Alexandros P, Haritakis Costas N, Zacharis Evangelos A, Nyktari Eva G, Vardas Panos E
Department of Cardiology, Heraklion University Hospital, Crete, Greece.
Eur J Heart Fail. 2008 May;10(5):475-81. doi: 10.1016/j.ejheart.2008.03.003. Epub 2008 Apr 8.
Brain natriuretic peptide (BNP) and left ventricular (LV) inotropic reserve are major prognostic indexes in heart failure (HF).
To investigate the relationship between N-terminal-proBNP (NT-proBNP) changes in response to dobutamine stress echocardiography (DSE) and the LV inotropic reserve, in HF patients with dilated cardiomyopathy (DC).
We studied 41 patients with DC, LVEF 31.6+/-7.7%, NYHA class II-III and 15 controls. Plasma NT-proBNP levels were measured before and 60 min after three 5-min stages of dobutamine (5 to 15 microg/kg/min).
Based on NT-proBNP changes in response to dobutamine, patients were categorized into two groups: In Group A circulating NT-proBNP levels fell (-16.6+/-7.8%), and in Group B they increased (8.4+/-9.1%). Group A had a marked improvement in WMSI compared to Group B (32.1+/-9.7% vs. 18.8+/-15.9%, p<0.001). Multivariate analysis showed that NT-proBNP changes were an independent predictor of LV inotropic reserve (b= -0.55, p<0.001). A reduction of 21.3% in plasma NT-proBNP levels in response to dobutamine predicted an improvement in WMSI of >25% with a sensitivity of 100% and a specificity of 92.3%.
NT-proBNP changes in response to dobutamine reflect improvement in LV contractility and constitute an independent predictor of LV inotropic reserve in patients with DC.
脑钠肽（BNP）和左心室（LV）变力性储备是心力衰竭（HF）的主要预后指标。
研究扩张型心肌病（DC）所致HF患者中，N末端B型利钠肽原（NT-proBNP）对多巴酚丁胺负荷超声心动图（DSE）的反应变化与左心室变力性储备之间的关系。
我们研究了41例DC患者，左心室射血分数（LVEF）为31.6±7.7%，纽约心脏协会（NYHA）心功能分级为II-III级，以及15名对照者。在多巴酚丁胺（5至15微克/千克/分钟）三个5分钟阶段之前和之后60分钟测量血浆NT-proBNP水平。
根据NT-proBNP对多巴酚丁胺的反应变化，患者被分为两组：A组循环NT-proBNP水平下降（-16.6±7.8%），B组升高（8.4±9.1%）。与B组相比，A组的室壁运动记分指数（WMSI）有显著改善（32.1±9.7%对18.8±15.9%，p<0.001）。多变量分析显示，NT-proBNP变化是左心室变力性储备的独立预测因子（b = -0.55，p<0.001）。多巴酚丁胺使血浆NT-proBNP水平降低21.3%预测WMSI改善>25%，敏感性为100%，特异性为92.3%。
NT-proBNP对多巴酚丁胺的反应变化反映左心室收缩性改善，并构成DC患者左心室变力性储备的独立预测因子。
