IEEE Trans Biomed Eng. 2020 Mar;67(3):905-914. doi: 10.1109/TBME.2019.2923587. Epub 2019 Jun 18.
The present study addresses the problem of estimating the respiratory rate from the morphological ECG variations in the presence of atrial fibrillatory waves (f-waves). The significance of performing f-wave suppression before respiratory rate estimation is investigated.
The performance of a novel approach to ECG-derived respiration, named "slope range" (SR) and designed particularly for operation in atrial fibrillation (AF), is compared to that of two well-known methods based on either R-wave angle (RA) or QRS loop rotation angle (LA). A novel rule is proposed for spectral peak selection in respiratory rate estimation. The suppression of f-waves is accomplished using signal- and noise-dependent QRS weighted averaging. The performance evaluation embraces real as well as simulated ECG signals acquired from patients with persistent AF; the estimation error of the respiratory rate is determined for both types of signals.
Using real ECG signals and reference respiratory signals, rate estimation without f-wave suppression resulted in a median error of 0.015 ± 0.021 Hz and 0.019 ± 0.025 Hz for SR and RA, respectively, whereas LA with f-wave suppression resulted in 0.034 ± 0.039 Hz. Using simulated signals, the results also demonstrate that f-wave suppression is superfluous for SR and RA, whereas it is essential for LA.
The results show that SR offers the best performance as well as computational simplicity since f-wave suppression is not needed.
The respiratory rate can be robustly estimated from the ECG in the presence of AF.
本研究旨在解决在存在心房颤动波（f 波）的情况下从心电图形态变化估计呼吸频率的问题。研究了在进行呼吸频率估计之前进行 f 波抑制的重要性。
将一种新的心电图衍生呼吸方法“斜率范围”（SR）与基于 R 波角度（RA）或 QRS 环旋转角度（LA）的两种知名方法进行比较。提出了一种用于呼吸率估计的谱峰选择的新规则。使用信号和噪声相关的 QRS 加权平均来实现 f 波的抑制。评估包括从持续性房颤患者采集的真实和模拟心电图信号；确定两种类型的信号的呼吸率估计误差。
使用真实的心电图信号和参考呼吸信号，在没有 f 波抑制的情况下，SR 和 RA 的估计误差中位数分别为 0.015 ± 0.021 Hz 和 0.019 ± 0.025 Hz，而 LA 在有 f 波抑制的情况下为 0.034 ± 0.039 Hz。使用模拟信号的结果也表明，SR 和 RA 不需要 f 波抑制，而 LA 则需要 f 波抑制。
结果表明，SR 提供了最佳的性能和计算简单性，因为不需要 f 波抑制。
在房颤的情况下，可以从心电图中稳健地估计呼吸频率。
