Utility of cyclic variation of heart rate score as a screening tool for sleep-disordered breathing in patients with heart failure

Night‐to‐night variability of sleep apnea detected by cyclic variation of heart rate during long‐term continuous ECG monitoring

“…In this study, an algorithm of the auto‐correlated wave detection with adaptive threshold was used to detect CVHR and Fcv was used to estimate AHI. The usefulness of the CVHR as a maker of sleep apnea has been reported by many researchers (Arikawa et al, 2020; Guilleminault et al, 1984; Hayano et al, 2011; Hsu et al, 2020; Magnusdottir & Hilmisson, 2018; Shimizu et al, 2015; Yatsu et al, 2021), and the accuracy of AHI estimation by Fcv has been confirmed by several earlier studies (Hayano et al, 2011, 2013, 2020, 2021). In a study of 864 polysomnographic subjects with suspected sleep apnea, patients with AHI > 15 were detected with a sensitivity of 83% and specificity of 88% by using Fcv > 15 cph as a criterion (Hayano et al, 2011).…”

“…In this study, we applied an ECG-based screening method of sleep apnea on seven-day continuous ECG monitoring, which has recently become available in clinical practice. Studies analyzing R-R interval variability of ECG during polysomnography have reported that the frequency of cyclic variation of heart rate (CVHR) reflects the AHI (Arikawa et al, 2020;Hayano et al, 2011Hayano et al, , 2013Hsu et al, 2020;Magnusdottir & Hilmisson, 2018;Yatsu et al, 2021). CVHR is a characteristic heart rate variability that appears with the episodes of sleep apnea and consists of bradycardia during apnea and transient tachycardia at the cessation of apnea (Guilleminault et al, 1984).…”