Purpose: Transpulmonary biomarkers may provide insight into pulmonary hypertension (PH) pathophysiology, but require cardiac catheterization. We investigated whether the peripheral arterial–venous ratio (PR) could substitute for the transpulmonary ratio (TPR).

Materials and methods: Blood from the pulmonary artery (PA), pulmonary arterial wedge (PAW), peripheral venous, and peripheral arterial positions was analysed for ET-1, NT-pro-BNP and cAMP levels in subjects with no PH (n = 18) and PH due to left heart disease (PH-LHD), which included combined pre- and post-capillary PH (Cpc-PH; n = 7) and isolated post-capillary PH (Ipc-PH; n = 9). Bland–Altman comparisons were made between peripheral venous and PA samples and between peripheral arterial and PAW samples. TPR was defined as [PAW]/[PA].

Results: For ET-1, Bland–Altman analysis indicated negative bias (−24%) in peripheral arterial compared to PAW concentration and positive bias (23%) in peripheral venous compared to PA concentration. There was <10% absolute bias for NT-pro-BNP and cAMP. For ET-1, there was no difference in PR between Cpc-PH and Ipc-PH (0.87 ± 0.4 vs. 0.94 ± 0.6, p = 0.8), whereas there was a difference in TPR (2.2 ± 1.1 vs. 1.1 ± 0.2, p < 0.05).

Conclusions: In PH-LHD, peripheral samples may be inadequate surrogates for transpulmonary samples, particularly when measuring mediators with prominent pulmonary secretion or clearance, such as ET-1.

目的：跨肺生物标志物可以深入了解肺动脉高压（PH）的病理生理学，但需要心导管检查。我们研究了外周动静脉比（PR）是否可以替代跨肺比（TPR）。

材料和方法：对无 PH 的受试者的肺动脉 (PA)、肺动脉楔 (PAW)、外周静脉和外周动脉位置的血液进行 ET-1、NT-pro-BNP 和 cAMP 水平分析（n  = 18) 和左心疾病引起的 PH (PH-LHD)，其中包括毛细血管前和毛细血管后合并的 PH (Cpc-PH；n  = 7) 和单独的毛细血管后 PH (Ipc-PH；n  = 9)。在外周静脉和 PA 样本之间以及外周动脉和 PAW 样本之间进行了 Bland-Altman 比较。TPR 定义为[PAW]/[PA]。

结果：对于 ET-1，Bland-Altman 分析表明，与 PAW 浓度相比，外周动脉存在负偏差 (−24%)，与 PA 浓度相比，外周静脉存在正偏差 (23%)。NT-pro-BNP 和 cAMP 的绝对偏差<10%。对于 ET-1，Cpc-PH 和 Ipc-PH 之间的 PR 没有差异（0.87 ± 0.4与0.94 ± 0.6，p  = 0.8），而 TPR 则存在差异（2.2 ± 1.1与1.1 ± 0.2） ，p  < 0.05）。

结论：在 PH-LHD 中，外周样本可能不足以替代经肺样本，特别是在测量具有显着肺部分泌或清除的介质（例如 ET-1）时。