The effect of obstructive sleep apnea on QRS complex morphology

Ljuba Bacharova; Epameinondas Triantafyllou; Christos Vazaios; Ivana Tomeckova; Ivana Paranicova; Ruzena Tkacova

doi:10.1016/j.jelectrocard.2014.12.007

The effect of obstructive sleep apnea on QRS complex morphology

J Electrocardiol. 2015 Mar-Apr;48(2):164-70. doi: 10.1016/j.jelectrocard.2014.12.007. Epub 2014 Dec 11.

Authors

Ljuba Bacharova¹, Epameinondas Triantafyllou², Christos Vazaios², Ivana Tomeckova³, Ivana Paranicova⁴, Ruzena Tkacova³

Affiliations

¹ International Laser Center, Bratislava, Slovakia; Institute of Pathological Physiology, Medical Faculty, Comenius University, Bratislava, Slovakia. Electronic address: bacharova@ilc.sk.
² Institute of Pathological Physiology, Medical Faculty, Comenius University, Bratislava, Slovakia.
³ Department of Respiratory Medicine, Faculty of Medicine, P.J. Safarik University, Kosice, Slovakia; L. Pasteur University Hospital, Kosice, Slovakia.
⁴ Department of Respiratory Medicine, Faculty of Medicine, P.J. Safarik University, Kosice, Slovakia.

PMID: 25541278
DOI: 10.1016/j.jelectrocard.2014.12.007

Abstract

Background: Obstructive sleep apnea (OSA) has been reported to be associated with an increased risk of ventricular arrhythmias and conduction disturbances. The aim of this study was to analyze the QRS complex morphology potentially indicative of intraventricular conduction impairment in patients with mild to severe OSA.

Material and methods: One hundred ninety-three consecutive patients, who underwent complete overnight polysomnography, were divided into four groups based on the OSA severity: (1) no OSA, (2) mild OSA, (3) moderate OSA and (4) severe OSA (apnea-hypopnea index <5, 5-15, 15-30, >30/h, respectively). Resting 12-lead ECG was recorded, the QRS parameters included QRS amplitude in individual leads, QRS spatial vector magnitude (QRSmax), electrical axis (EA), ECG criteria for left ventricular hypertrophy (ECG-LVH) and right ventricular hypertrophy (ECG-RVH), and occurrence of fragmented QRS (fQRS).

Results: Severity of OSA was significantly associated with a gradual significant shift of the electrical axis to the left (45.5±22.5°; 34.8±17.1°; 32.9±18.2°; 29.8±10.0°; respectively), while the QRSmax values were low in all patient groups, with a significant difference between no OSA and severe OSA groups. The multivariate analysis showed that QRSmax was independently associated with age and the interaction between gender and OSA severity (p=0.001, and p=0.004, respectively; adjusted R(2)=0.178). The electrical axis was found to be independently associated with age and OSA severity (p=0.037, and p=0.026, respectively; R(2)=0.109). Changes of electrical axis and of QRSmax were reflected in corresponding changes in the amplitude of 12-lead ECG and in low occurrence of ECG-LVH and ECG-RVH criteria. The OSA groups had higher occurrence of fQRS.

Conclusion: OSA patients displayed a combination of changes in QRS complex morphology, the leftward shift of EA, low QRS voltage and fQRS, suggestive of depolarization sequence deterioration that might be indicative of considerable electrical remodeling.

Keywords: Electrical axis; Fragmented QRS complex; QRS complex; QRS voltage; Sleep apnea.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Aged, 80 and over
Arrhythmias, Cardiac / etiology*
Arrhythmias, Cardiac / physiopathology
Brugada Syndrome
Cardiac Conduction System Disease
Electrocardiography
Female
Heart Conduction System / abnormalities*
Heart Conduction System / physiopathology
Humans
Hypertrophy, Left Ventricular / etiology
Hypertrophy, Left Ventricular / physiopathology
Hypertrophy, Right Ventricular / etiology
Hypertrophy, Right Ventricular / physiopathology
Male
Middle Aged
Polysomnography
Prospective Studies
Risk Factors
Severity of Illness Index
Sleep Apnea, Obstructive / complications*
Sleep Apnea, Obstructive / physiopathology