Patients with heart failure or OSA (obstructive sleep apnoea) have reduced HF-HRV (high-frequency heart rate variability), indicating reduced cardiac vagal modulation, a marker of poor prognosis. CPAP (continuous positive airway pressure) abolishes OSA in patients with heart failure, but effects on daytime HF-HRV have not been determined. We hypothesized that, in patients with heart failure, treatment of coexisting OSA by CPAP would increase morning HF-HRV. In 19 patients with heart failure (left ventricular ejection fraction <45%) and OSA (≥20 apnoeas and hypopnoeas/h of sleep), HF-HRV was quantified before and 1 month after randomization to a control or CPAP-treated group. In the control group (n=7), there were no changes in HF-HRV over the 1 month study during wakefulness in the morning. In the CPAP-treated group (n=12) HF-HRV increased significantly during wakefulness in the morning [from 2.43±0.55 to 2.82±0.50 log(ms2/Hz); P=0.002] due to an increase in transfer function between changes in lung volume and changes in HF-HRV (92.37±96.03 to 219.07±177.14 ms/l; P=0.01). In conclusion, treatment of coexisting OSA by nocturnal CPAP in patients with heart failure increases HF-HRV during morning wakefulness, indicating improved vagal modulation of heart rate. This may contribute to improved prognosis.
Continuous positive airway pressure increases heart rate variability in heart failure patients with obstructive sleep apnoea
- Views Icon Views
- Share Icon Share
Matthew P. Gilman, John S. Floras, Kengo Usui, Yasuyuki Kaneko, Richard S. T. Leung, T. Douglas Bradley; Continuous positive airway pressure increases heart rate variability in heart failure patients with obstructive sleep apnoea. Clin Sci (Lond) 1 February 2008; 114 (3): 243–249. doi: https://doi.org/10.1042/CS20070172
Download citation file: