Effects of Obstructive Sleep Apnea and its Treatment on Signal-Averaged P-Wave Duration in Men

Abstract

The online-only Data Supplement is available at http://circep.ahajournals.org/lookup/suppl/doi:10.1161/CIRCEP.113.000266/-/DC1. Correspondence to Ken-ichi Maeno, MD, Sleep Center, Toranomon Hospital, 2-2-2 Toranomon, Minato-ku, Tokyo 105-8470, Japan, E-mail maeken@zk9.so-net.ne.jp Background-Prolonged P-wave duration, indicating atrial conduction delay, is a potent precursor of atrial fibrillation.Obstructive sleep apnea (OSA) is a risk factor for atrial fibrillation development. We investigated the association of P-wave duration with OSA and its treatment. Methods and Results-We enrolled 80 consecutive men with normal sinus rhythms who underwent polysomnography, had no history of atrial fibrillation or ischemic heart disease, and no evidence of heart failure. Signal-averaged P-wave duration (SAPWD) was measured in all participants. Multivariable regression analysis showed that age, hypertension, and log-transformed apnea-hypopnea index were significantly and independently correlated with SAPWD. SAPWD was repeatedly measured after 1 month of continuous positive airway pressure (CPAP) therapy in 62 patients with moderateto-severe OSA. As controls, 18 patients with moderate-to-severe OSA were enrolled. Their SAPWD was also measured at baseline and after 1 month without CPAP therapy. No significant change in SAPWD was found between baseline and after 1 month in the controls. However, SAPWD was significantly shortened after 1 month of CPAP therapy (from 137.5±8.6 to 129.7±8.5 ms; P<0.001), and the SAPWD change was significantly different in patients with CPAP therapy compared with controls (P<0.001). In addition, the SAPWD change in patients with CPAP therapy correlated inversely with nightly CPAP usage (r=−0.52; P<0.001). Conclusions-OSA severity was significantly associated with prolonged SAPWD. CPAP therapy significantly shortened SAPWD in patients with moderate-to-severe OSA. Thus, OSA may cause atrial conduction disturbances, leading to an increased risk of atrial fibrillation development, which may be modifiable by alleviating OSA with CPAP therapy. (Circ Arrhythm Electrophysiol. 2013;6:287-293.)

Atrial Fibrillation Promotion With Long-Term Repetitive Obstructive Sleep Apnea in a Rat Model

“…Atrial and atrioventricular (AV) conducting system ERPs were defined as the longest S1-S2 coupling interval failing to generate a propagated beat. To assess atrial tachyarrhythmia inducibility, 25-Hz burst pacing (pulse width 2 ms, 4 Â threshold current) was applied for 3 s, with 6 3-s burst cycles separated by 1-s intervals. AF was defined as a rapid (>800 beats/min) irregular atrial rhythm, and AF inducibility was defined as AF lasting for at least 1 s immediately after the 6-burst cycle protocol.…”

“…Patients with OSA exhibit prolonged atrial conduction times, longer P waves, slowed atrial conduction velocities, lower atrial electrogram voltages, and more complex electrograms (11,24). Signal-averaged P-wave duration is increased by OSA and significantly decreases Repetitive OSA Causes AF-Promoting Remodeling with continuous positive airway pressure treatment (25). OSA is also associated with LV hypertrophy and dilation, as well as an increased risk of systolic dysfunction (26).…”

EHRA/HRS/APHRS/SOLAECE expert consensus on atrial cardiomyopathies: definition, characterization, and clinical implication

“…117,118 Signal-averaged P-wave duration is increased by OSA, and decreases significantly with continuous positive airway pressure treatment. 120 In a rat model, repeated obstructive apnoea over a 4-week period increases AF vulnerability and slows atrial conduction by altering connexin-43 expression and inducing atrial fibrosis. 121 …”

Relationship Between Severity of Obstructive Sleep Apnea and PR Interval

“…Arousal increases vagal tone in the transmission structures of the heart, which increases the PR interval. Maeno et al demonstrated that apnea/hypopnea prolongs the P wave independently (10) . Somer et al showed that barorefl ex distortion and the increase of chemo-refl ex response are due to sympathetic and parasympathetic changes in patients (11) .…”