Author + information
- Paweł T. Matusik, MD, PhD and
- Phyllis K. Stein, PhD∗ ()
- ↵∗Department of Medicine, Cardiovascular Division, Washington University School of Medicine, Saint Louis, Missouri 63110
We have read the paper by Javaheri et al. (1) with great interest. We agree with the investigators that treatment of sleep apnea (SA) may be extremely beneficial to many groups of patients with cardiovascular disease (CVD) (1). We would like to point out that early diagnosis of SA may play an important role in preventing CVD morbidity. Importantly, the presence of SA is associated with characteristic cyclic variation of heart rate (CVHR) patterns, which can be found on Holter electrocardiographic (ECG) monitoring. It has been shown that the number of CVHRs per hour (CVHR index) is strongly correlated with the apnea−hypopnea index (AHI) (2). In patients with heart failure, the CVHR score was also shown to correlate with the respiratory disturbance index, which was closely correlated with the AHI obtained by polysomnography (3). Obstructive sleep apnea (OSA) and Cheyne-Stokes respiration with central sleep apnea (CSA) differ in regard to autonomic heart rate control. The greatest heart rate changes are seen during the apneic phase of OSA. In contrast, in CSA, heart rate changes are nearly absent during apnea (3). These abnormal heart rate patterns are distinct from respiratory sinus arrhythmia and may be easily differentiated by visual analysis of beat-to-beat heart rate tachograms (4).
Patients with SA risk factors and/or CVD frequently undergo Holter monitoring for various clinical indications. Wide introduction of specific continuous ECG-based SA indexes into clinical practice (2,3) or even simple screening of patterns derived from Holter ECG tachograms (4) may be a way to identify those patients who may benefit from detailed SA diagnostics and treatment.
Please note: This work was supported by the Faculty of Medicine of Jagiellonian University Medical College (Leading National Research Centre 2012–2017). The supporting institution had no role in the design and conduct of the study, in the collection, analysis, and interpretation of the data, and in the preparation, review, or approval of the paper. Both authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2017 American College of Cardiology Foundation
- Javaheri S.,
- Barbe F.,
- Campos-Rodriguez F.,
- et al.
- Shimizu T.,
- Yoshihisa A.,
- Iwaya S.,
- et al.