Havelka Erika G, Rzechula Kathleen H, Bryant Tyson O, Anneken Steve M, Kulstad Erik B
Department of Emergency Medicine, Advocate Christ Medical Center, Oak Lawn, Illinois, USA.
J Emerg Med. 2011 Feb;40(2):146-50. doi: 10.1016/j.jemermed.2008.01.019. Epub 2008 Sep 14.
Both serum measurements of B-type natriuretic peptide (BNP) and impedance cardiography (ICG) are used to evaluate patients for congestive heart failure (CHF) in the Emergency Department (ED), but the agreement between the data obtained by these two methods remains uncertain.
We sought to measure the correlation between BNP levels and ICG measurements in patients presenting to the ED with dyspnea, and compare the diagnostic accuracy of each method in diagnosing CHF.
We performed a prospective observational study of a convenience sample of patients presenting to the ED with dyspnea and being evaluated for CHF as a cause of their symptoms. An ICG measurement was obtained on each patient and the correlation between BNP level and the ICG parameters cardiac index (CI), systemic vascular resistance (SVR), and thoracic fluid content (TFC) was measured. To further quantify the diagnostic accuracy of ICG and BNP, we then constructed receiver operating characteristic curves based on discharge diagnosis of CHF and compared the area under the curve (AUC) of each test.
Out of 54 patients enrolled, correlation was poor between BNP and CI (Spearman's ρ = -.07, p = 0.64) and between BNP and SVR (Spearman's ρ = -.10, p = 0.46), but moderate between BNP and TFC (Spearman's ρ = .32, p = 0.02); a wide degree of scatter was seen in all correlations. BNP levels showed the best diagnostic accuracy for a discharge diagnosis of CHF, with an AUC of .77 (95% confidence interval .59-.95), whereas CI had an AUC of .72 (95% confidence interval .55-.88).
We found limited correlation between BNP levels and ICG parameters, suggesting that, in our population, the two tests may not consistently give similar information. BNP level and CI both provided only fair diagnostic accuracy for discharge diagnosis of CHF.
在急诊科（ED），B型利钠肽（BNP）的血清检测和阻抗心动图（ICG）均用于评估充血性心力衰竭（CHF）患者，但这两种方法所获数据之间的一致性仍不确定。
我们试图测定因呼吸困难就诊于急诊科且接受CHF评估的患者中BNP水平与ICG检测结果之间的相关性，并比较每种方法在诊断CHF方面的诊断准确性。
我们对因呼吸困难就诊于急诊科并被评估CHF为症状病因的便利样本患者进行了一项前瞻性观察性研究。对每位患者进行ICG检测，并测定BNP水平与ICG参数心脏指数（CI）、全身血管阻力（SVR）和胸腔积液含量（TFC）之间的相关性。为进一步量化ICG和BNP的诊断准确性，我们随后根据CHF出院诊断构建了受试者工作特征曲线，并比较了每项检测的曲线下面积（AUC）。
在纳入的54例患者中，BNP与CI之间（Spearman相关系数ρ = -0.07，p = 0.64）以及BNP与SVR之间（Spearman相关系数ρ = -0.10，p = 0.46）的相关性较差，但BNP与TFC之间具有中等相关性（Spearman相关系数ρ = 0.32，p = 0.02）；所有相关性均存在广泛的离散度。对于CHF出院诊断，BNP水平显示出最佳诊断准确性，AUC为0.77（95%置信区间0.59 - 0.95），而CI的AUC为0.72（95%置信区间0.55 - 0.88）。
我们发现BNP水平与ICG参数之间的相关性有限，这表明在我们的研究人群中，这两种检测可能无法始终提供相似的信息。BNP水平和CI在CHF出院诊断方面的诊断准确性均仅为中等。
