Cassani Raymundo, Tiwari Abhishek, Falk Tiago H
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:914-917. doi: 10.1109/EMBC44109.2020.9175396.
Photoplethysmography (PPG) is a non-invasive, low-cost optical technique used to assess the cardiovascular system. In recent years, PPG-based heart rate measurement has gained significant attention due to its popularity in wearable devices, as well as its practicality relative to electrocardiography (ECG). Studies comparing the dynamics of ECG- and PPG-based heart rate measures have found small differences between these two modalities; differences related to the physiological processes behind each technique. In this work, we analyzed the spectral coherence and the signal-to-noise ratio between isolated PPG pulses and the raw PPG signal in order to: (i) determine the optimal filter to enhance pulse detection from raw PPG for improved heart rate estimation, and (ii) characterize the spectral content of the PPG pulse. The proposed methods were evaluated on 27000 pulses from a PPG database acquired from 42 participants (adults and children). The results showed that the optimal bandpass filter to enhance PPG from the adult group was 0.6-3.3 Hz, while for the children group it was 1.0-2.7 Hz. The spectral analysis on the pulse signal showed that similar bandwidths were found for the adult (0.8-2.4 Hz) and children (0.9-2.7 Hz) groups. We hope that the results presented herein serve as a baseline for pulse detection algorithms and assist with the development of more sophisticated PPG processing algorithms.
光电容积脉搏波描记法（PPG）是一种用于评估心血管系统的非侵入性、低成本光学技术。近年来，基于PPG的心率测量因其在可穿戴设备中的普及以及相对于心电图（ECG）的实用性而受到广泛关注。比较基于ECG和PPG的心率测量动态的研究发现，这两种方式之间存在微小差异；这些差异与每种技术背后的生理过程有关。在这项工作中，我们分析了孤立的PPG脉冲与原始PPG信号之间的频谱相干性和信噪比，以便：（i）确定用于增强从原始PPG中检测脉搏以改善心率估计的最佳滤波器，以及（ii）表征PPG脉冲的频谱内容。所提出的方法在从42名参与者（成人和儿童）获取的PPG数据库中的27000个脉冲上进行了评估。结果表明，用于增强成人组PPG的最佳带通滤波器为0.6 - 3.3 Hz，而儿童组为1.0 - 2.7 Hz。对脉搏信号的频谱分析表明，成人组（0.8 - 2.4 Hz）和儿童组（0.9 - 2.7 Hz）的带宽相似。我们希望本文所呈现的结果能够作为脉搏检测算法的基线，并有助于开发更复杂的PPG处理算法。
