Methods Inf Med 2014; 53(04): 303-307
DOI: 10.3414/ME13-02-0043
Focus Theme – Original Articles
Schattauer GmbH

Robust Detection of Sleep Apnea from Holter ECGs

Joint Assessment of Modulations in QRS Amplitude and Respiratory Myogram Interference
C. Maier
1   Institute of Medical Biometry and Informatics, Heidelberg University Hospital, Heidelberg, Germany
2   Department of Medical Informatics, Heilbronn University, Heilbronn, Germany
,
H. Wenz
3   Thoraxklinik, Heidelberg University Hospital, Heidelberg, Germany
,
H. Dickhaus
1   Institute of Medical Biometry and Informatics, Heidelberg University Hospital, Heidelberg, Germany
› Author Affiliations
Further Information

Publication History

received:22 October 2013

accepted:22 April 2014

Publication Date:
20 January 2018 (online)

Summary

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems”.

Objectives: Detect presence of sleep-related breathing disorders (SRBD) in epochs of 1 min by signal analysis of Holter ECG recordings.

Methods: In 121 patients, 140 synchronized polysomnograms (PSGs) and 8-channel Holter ECGs were recorded. The only excluded condition was persistent arrhythmias. Respiratory events as scored from the PSGs were mapped to a 1 min grid and served as reference for ECG-based detection. Moreover, 69/70 recordings of the Physionet Sleep Apnea ECG Database (PADB) were included. We performed receiver operating characteristics analysis of a single, novel time-domain feature, the joint local similarity index (jLSI). Based on cross-correlation, the jLSI quantifies the time-locked occurrence of characteristic low-frequency (LF) modulations in ECG respiratory myogram interference (RMI), QRS amplitude (QRSA) and heart rate.

Results: Joint oscillations in QRSA, RMI and the envelope of RMI identified positive epochs with a sensitivity of 0.855 (PADB: 0.873) and a specificity of 0.86 (PADB: 0.88). Inclusion of heart rate did not improve detection accuracy.

Conclusions: Joint occurrence of LF-modulations in QRSA and RMI is a characteristic feature of SRBD that is robustly quantified by the jLSI and permits reliable and reproducible detection of sleep apnea in very heterogeneous settings.