Reali Pierluigi, Tacchino Giulia, Rocco Giulia, Cerutti Sergio, Bianchi Anna Maria
Dept. of Electronics Information and Bioengineering, Politecnico di Milano, Italy.
Stud Health Technol Inform. 2019;261:128-133.
Heart Rate Variability (HRV) derived from standard one-lead electrocardiography (ECG) was compared with HRV computed by a commercial ECG shirt and with the inter-beat-intervals (IBI) measured by a research-grade photoplethysmographic (PPG) wristband. Signals from 8 subjects were recorded in three experimental phases: during sit; in upright position ("stand"); during controlled respiration. HRV and IBI from both the wearables were computed online (i.e. during the experiment) and stored for subsequent analyses, while the standard ECG was processed offline with state-of-the-art methods to obtain a clean reference HRV. Shirt and wristband signals accuracies were assessed, with respect to the reference HRV, through a between-phase and a beat-to-beat analyses. The former considered several time and frequency domain parameters; the latter was carried out through the Bland-Altman method. Time and frequency domain parameters computed from shirt HRV resulted very similar to the ones extracted from the reference HRV and generally more accurate than the parameters computed from wristband IBI. The Bland-Altman analysis showed that wristband IBI is significantly different from ECG-derived HRV, especially during "stand". Therefore, our results support the idea that some care should be paid in the interpretation of online PPG-derived IBI, while HRV measures online-derived from ECG-shirts seem to be more reliable in the analyzed conditions. The high number of missing beats also suggest that the design of wristband devices should be taken into account to reduce the rate of incorrect measurements, by maximizing sensor adhesion to the skin.
将源自标准单导联心电图（ECG）的心率变异性（HRV）与通过商用ECG衬衫计算得出的HRV以及通过研究级光电容积脉搏波描记法（PPG）腕带测量的逐搏间期（IBI）进行了比较。在三个实验阶段记录了8名受试者的信号：坐着时；直立姿势（“站立”）；控制呼吸期间。两种可穿戴设备的HRV和IBI均在在线状态下（即实验期间）进行计算并存储以供后续分析，而标准ECG则采用先进方法进行离线处理以获得纯净的参考HRV。通过阶段间分析和逐搏分析，相对于参考HRV评估了衬衫和腕带信号的准确性。前者考虑了多个时域和频域参数；后者通过布兰德-奥特曼方法进行。从衬衫HRV计算得出的时域和频域参数与从参考HRV提取的参数非常相似，并且通常比从腕带IBI计算得出的参数更准确。布兰德-奥特曼分析表明，腕带IBI与源自ECG的HRV有显著差异，尤其是在“站立”期间。因此，我们的结果支持这样一种观点，即在解释在线PPG衍生的IBI时应谨慎，而在分析条件下，源自ECG衬衫的在线HRV测量似乎更可靠。大量漏搏还表明，应考虑腕带设备的设计，通过最大化传感器与皮肤的附着力来降低错误测量率。
