The effects of simulated obstructive apnea and hypopnea on arrhythmic potential in healthy subjects

Journal article

Preliminary evidence supports an association between OSA and cardiac dysrhythmias. Negative intrathoracic pressure, as occurring during OSA, may provoke cardiac dysrhythmias. Thus, we aimed to study the acute effects of simulated apnea and hypopnea on arrhythmic potential and measures of cardiac repolarization [QT and T to T intervals (TT] in humans. In 41 healthy volunteers, ECG was continuously recorded prior, during and after simulated obstructive hypopnea (inspiration through a threshold load), simulated apnea (Mueller maneuver), end-expiratory central apnea and normal breathing in randomized order. The number of subjects with premature beats was significantly higher during inspiration through a threshold load (n = 7), and the Mueller maneuver (n = 7) compared to normal breathing (n = 0) (p = 0.008 for all comparisons), but not during end-expiratory central apnea (n = 3, p = 0.125). Inspiration through a threshold load was associated with a non-significant mean (SD) increase of the QT interval [+5.4 (22.4) ms, 95 %CI -1.7 to +12.4 ms, p = 0.168] and a significant increase of the TT interval [+3.7 (8.9) ms, 95 %CI +0.9 to +6.6 ms, p = 0.010]. The Mueller maneuver induced a significant increase of the QT interval [+8.3 (23.4) ms, 95 %CI 0.9 to +15.6 ms, p = 0.035] and the TT interval (+4.2 (8.2) ms, 95 %CI +1.6 to +6.8 ms, p = 0.002). There were no significant changes of the QT and TT intervals during central end-expiratory apnea. These data indicate that simulated obstructive apnea and hypopnea are associated with an increase of premature beats and prolongation of QT and TT intervals. Therefore, negative intrathoracic pressure changes may be a contributory mechanism for the association between OSA and cardiac dysrhythmias. © 2012 Springer-Verlag.

Authors: Camen, G; Clarenbach, C; Stöwhas, A; Rossi, V; Sievi, N

• Journal: European Journal of Applied Physiology
• Volume: 113
• Issue: 2
• Pages: 489-496
• Publication date: 2013-02-01
• DOI: 10.1007/s00421-012-2457-y
• ISSN: 1439-6319