Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
School of Health and Wellbeing, University of Glasgow, Glasgow, UK.
BMJ Open Respir Res. 2024 Mar 22;11(1):e002124. doi: 10.1136/bmjresp-2023-002124.
N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a biomarker of cardiac ventricular wall stress that is incorporated into pulmonary hypertension (PH) risk stratification models. Sendaway sampling may enable patients to perform NT-proBNP tests remotely. This UK-wide study aimed to assess the agreement of sendaway NT-proBNP with standard venous NT-proBNP and to assess the effect of delayed processing.
Reference venous NT-proBNP was collected from PH patients. Samples for capillary and venous sendaway tests were collected contemporaneously, mailed to a reference laboratory and processed at 3 and 7 days using a Roche Cobas e411 device. Differences in paired measurements were analysed with Passing-Bablok regression, percentage difference plots and the % difference in risk strata.
113 patients were included in the study. 13% of day 3 capillary samples were insufficient. Day 3 capillary samples were not equivalent to reference samples (Passing Bablok analysis slope of 0.91 (95% CI 0.88 to 0.93) and intercept of 6.0 (95% CI 0.2 to 15.9)). The relative median difference was -7% and there were acceptable limits of agreement. Day 3 capillary NT-proBNP accurately risk stratified patients in 93.5% of cases. By comparison, day 3 venous results accurately risk stratified patients in 90.1% of cases and were equivalent by Passing-Bablok regression. Delayed sampling of sendaway tests led to an unacceptable level of agreement and systematically underestimated NT-proBNP.
Sendaway NT-proBNP sampling may provide an objective measure of right ventricular strain for virtual PH clinics. Results must be interpreted with caution in cases of delayed sampling.
N 端脑利钠肽前体（NT-proBNP）是一种心脏心室壁张力的生物标志物，被纳入肺动脉高压（PH）风险分层模型。邮寄采样可以使患者能够远程进行 NT-proBNP 测试。这项英国范围内的研究旨在评估邮寄 NT-proBNP 与标准静脉 NT-proBNP 的一致性，并评估延迟处理的效果。
从 PH 患者中采集参考静脉 NT-proBNP。同时采集毛细血管和静脉邮寄测试样本，邮寄至参考实验室，使用罗氏 Cobas e411 设备在 3 天和 7 天进行处理。使用 Passing-Bablok 回归、差异百分比图和风险分层差异百分比分析配对测量的差异。
研究纳入了 113 名患者。第 3 天的毛细血管样本中有 13%不足。第 3 天的毛细血管样本与参考样本不一致（Passing Bablok 分析斜率为 0.91（95%CI 0.88 至 0.93），截距为 6.0（95%CI 0.2 至 15.9））。相对中位数差异为-7%，且有可接受的一致性界限。第 3 天的毛细血管 NT-proBNP 能够准确地对 93.5%的患者进行风险分层。相比之下，第 3 天的静脉结果能够准确地对 90.1%的患者进行风险分层，并且通过 Passing-Bablok 回归是等效的。邮寄测试的延迟采样导致了不可接受的一致性水平，并系统地低估了 NT-proBNP。
邮寄 NT-proBNP 采样可以为虚拟 PH 诊所提供右心室应变的客观测量。在延迟采样的情况下，结果必须谨慎解释。
