The Effect of Sleep Apnea on QT Interval, QT Dispersion, and Arrhythmias

Abstract

Background: QT interval (QT) and QT dispersion (QTd) are electrocardiograph (ECG) parameters for the evaluation of myocardial repolarization. The inhomogeneity of ventricular repolarization is associated with ventricular arrhythmias. An increased QT, QTd, and increased incidence of nocturnal cardiac rhythm disturbances have been described in patients with obstructive sleep apnea (OSA), while other investigators did not find a relationship between ventricular arrhythmias and OSA. Hypothesis: The aim of this study was to examine the occurrence of ventricular arrhythmias and to measure QT parameters in patients with untreated OSA using an ambulatory Holter-ECG. Methods: A total of 25 patients with untreated OSA were studied. After routine biochemical investigation and 2-dimensional, M-mode echocardiography, a 24-hour Holter-ECG was recorded to detect cardiac arrhythmias and QT parameters. QT parameters were measured by the QT Guard system. Results: Only the QT interval increased significantly during the nighttime period (nocturnal QT interval: 423.1 ± 34.6 ms, daytime QT interval: 381.6 ± 33.8 ms, 24-hour QT interval: 394.7 ± 31.1 ms). However, during the nighttime QT interval (422.8 ± 14.9 ms), QTd (31.2 ± 11.0 ms) and QT dispersion (30.5 ± 10.2 ms) did not show any change compared to 24-hour (QTc interval: 423.7 ± 14.2 ms, QTd: 28.8 ± 9.4 ms, QTcd: 30.5 ± 9.43 ms) and daytime levels (QTc interval: 423.9 ± 14.3 ms, QTd: 27.3 ± 10.7 ms, QTcd: 29.9 ± 11.1 ms). None of the patients had ventricular arrhythmias. Conclusions: QTd and QTcd did not increase during the nighttime period. Our study did not show an increased risk of ventricular arrhythmias in this population during the monitoring period.

Sleep-Disordered Breathing and Cardiac Arrhythmias

“…33 OSA similarly impacts QT dispersion and Twave alternans, which might predispose these patients to malignant arrhythmias and SCD. [34][35][36][37] Bradyarrhythmias in OSA are linked with vagal activation that can be found at the end of apneic events. Vagal activation is mediated by hypoxemic triggering of the glomus caroticum.…”

Obstructive sleep apnea and cardiovascular risk in children

“…В частности, усиление симпатической иннервации сердца сопровождается повышением дисперсии интервала Q-T -максимальной разни-цы продолжительности интервалов Q-T в пределах 12 отведений ЭКГ. Повышенная дисперсия интерва-ла Q-T, в свою очередь, может предрасполагать к раз-витию нарушений ритма сердца [21]. Проведенный метаанализ публикаций позволил выявить, что у лиц с апноэ сна имелись статистически достоверно более…”

A new tool for QT interval analysis during sleep in healthy and obstructive sleep apnea subjects: a study on women

“…By monitoring the QT interval during sleep, it is possible to create a link between the ventricular repolarization and sleep stages. Many groups have reported their approaches, results, and assessments about the effects of sleep disorders and their treatments [2][3][4], panic disorder [5], sleep position [6], menopause and hormone replacement [7], caffeine intake [8], and drug intake [9,10] on the QT interval.…”

“…Specifically, the variations of the QT interval related to sleep disorders such as obstructive sleep apnea (OSA) have been investigated in the last 20 years [2,3,11]. OSA is a complete or near complete cessation of airflow due to the obstruction of the upper airway for at least 10 s. Although it is a respiratory event, it affects the cardiovascular system.…”