University of Heidelberg, Heidelberg, Germany.
Roche Diagnostics International, Switzerland.
J Card Fail. 2017 Dec;23(12):835-842. doi: 10.1016/j.cardfail.2017.07.404. Epub 2017 Jul 27.
Biologic variation of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in chronic heart failure (CHF) may affect blood levels and risk stratification. The sources of NT-proBNP variation are unknown.
We performed NT-proBNP measurements and clinical and hemodynamic assessments in 50 patients with heart failure with reduced ejection fraction (HFrEF) who met criteria for clinical stability over 2 time intervals. Hemodynamic variables were measured with the use of inert gas rebreathing and impedance cardiography. Heart rhythm was monitored with the use of external electrocardiographic event recorders throughout the study. Determinants of NT-proBNP-levels and both absolute (ΔNT-proBNP) and relative (ΔNT-proBNP) changes at 1-week and 2-week intervals were identified with the use of univariable and multivariable linear mixed-effects models and linear regression analyses, respectively. Clinical and hemodynamic variables did not significantly change between study visits. The individual variation of NT-proBNP at 2 weeks was 9.2% (range 3.9%-18.6%). Weight and glomerular filtration rate were independently associated with baseline NT-proBNP concentrations (P = .01 and P = .005, respectively). There was no relationship between absolute and relative changes of NT-proBNP at 1-week intervals and changes in clinical and hemodynamic variables. Absolute change of NT-proBNP at 2-week intervals was associated with absolute change in left cardiac work index (P = .008), and relative change in NT-proBNP at 2-week intervals was determined by relative change of thoracic fluid content index (P = .008) and diastolic blood pressure (P = .01). The coefficients of determination (R) for the multivariable models with ΔNT-proBNP, ΔNT-proBNP, ΔNT-proBNP, and ΔNT-proBNP as dependent variables were 0.21, 0.19, 0.10, and 0.32, respectively.
In patients with stable HFrEF, changes in clinical and hemodynamic variables only marginally contribute to the variation of NT-proBNP.
N 端脑利钠肽前体（NT-proBNP）在慢性心力衰竭（CHF）中的生物学变异可能会影响血液水平和危险分层。NT-proBNP 变异的来源尚不清楚。
我们对 50 名射血分数降低的心力衰竭（HFrEF）患者进行了 NT-proBNP 测量和临床及血流动力学评估，这些患者在 2 个时间间隔内符合临床稳定标准。使用惰性气体再呼吸和阻抗心动图测量血流动力学变量。在整个研究过程中，使用外部心电图事件记录器监测心律。使用单变量和多变量线性混合效应模型和线性回归分析，分别确定 NT-proBNP 水平的决定因素以及 1 周和 2 周间隔的绝对（ΔNT-proBNP）和相对（ΔNT-proBNP）变化。研究访问期间，临床和血流动力学变量无显著变化。2 周时 NT-proBNP 的个体变异为 9.2%（范围 3.9%-18.6%）。体重和肾小球滤过率与基线 NT-proBNP 浓度独立相关（P = .01 和 P = .005）。1 周间隔时 NT-proBNP 的绝对和相对变化与临床和血流动力学变量的变化之间没有关系。2 周间隔时 NT-proBNP 的绝对变化与左心做功指数的绝对变化相关（P = .008），2 周间隔时 NT-proBNP 的相对变化由胸腔液含量指数的相对变化（P = .008）和舒张压（P = .01）决定。以ΔNT-proBNP、ΔNT-proBNP、ΔNT-proBNP 和ΔNT-proBNP 为因变量的多变量模型的决定系数（R）分别为 0.21、0.19、0.10 和 0.32。
在稳定的 HFrEF 患者中，临床和血流动力学变量的变化仅对 NT-proBNP 的变异有轻微贡献。
