The Clinical Utility of Electrocardiographic Holter Monitoring for Detecting Sleep Apnea

Objectives: Obstructive sleep apnea (OSA) is an emerging risk factor for cardiovascular disease and is mostly undiagnosed. Sudden changes in heart rate
mediated by the autonomic nervous system are observed during sleep apnea episodes. It is not clear whether the presence of cyclic variation of heart rate (CVHR) is useful in predicting OSA. The purpose of the present study was to estimate the diagnostic accuracy of electrocardiographic Holter monitoring to identify patients with significant OSA in a selected population compared to polysomnogram. Methods: 136 consecutive patients underwent polysomnography (PSG) and electrocardiogram (ECG) Holter monitoring simultaneously for eight hours during sleep-time. All data from the PSG, the ECG Holter recordings and the automated sleep apnea software were evaluated to compare patients with regard to cyclic variation of heart rate, apnea and hypopnea index (AHI) and sleep parameters.
Results: Patients diagnosed as severe OSA had longer duration of CVHR measured by the Holter monitoring. The likelihood of having significant OSA was directly
proportional to the presence and duration of the CVHR. There was a moderate correlation between the duration of the CVHR episodes and the AHI (r = 0.50;
P<0.0001; 95% CI; r=0.36 to 0.62). The diagnostic utility of CVHR detected on Holter monitoring in the detection of severe OSA was determined using receiver operating characteristic (ROC) curves, assuming AHI > 15 as references for severe OSA. We also described the likelihood ratios for OSA stratified by different ranks of CVHR duration.
Conclusion: Electrocardiographic Holter monitoring has good accuracy for the detection of significant OAS in a selected population and therefore can be considered as a valuable simplified technique.

The authors declare no conflict of interest.

Not applicable

The datasets used in this study are openly available at [repository link] and the source code is available on GitHub at [GitHub link].

This work did not receive any external funding.