Effects of physiological cardiac pacing on sleep-disordered breathing in patients with chronic bradydysrhythmias

In six patients with chronic bradydysrhythmias, polysomnographies were perf ormed before cardiac pacemaker implantation and over the week following imp lantation. A patient with third-degree atrioventricular block (AVB) and two patients with sinus node dysfunction (SND) were associated with sleep-diso rdered breathing (SDB). Their cardiac pacemaker therapies, with the increas e in the average heart rate, led to a reduction of apnea-hypopnea index and /or an improvement of Cheyne-Stokes breathing. It seems that chronic bradyd ysrhythmia is one of the causative factors leading to SDB.