High Prevalence of Sleep Apnea Syndrome in Patients With Long-Term Pacing: The European Multicenter Polysomnographic Study

Abstract

Background— Cardiovascular diseases leading to pacemaker implantations are suspected of being associated with a high rate of undiagnosed sleep apnea syndrome (SAS). We sought to determine the prevalence and consequences of SAS in pacemaker patients according to pacing indications: heart failure, symptomatic diurnal bradycardia, and atrioventricular block. Methods and Results— Ninety-eight consecutive patients (mean age, 64±8 years) not known to have sleep apnea were included; 29 patients were paced for dilated cardiomyopathy (29%), 33 for high-degree atrioventricular block (34%), and 36 for sinus node disease (37%). All underwent Epworth Sleepiness Scale assessment and polysomnography with the pacemaker programmed to right ventricular DDI pacing mode (lower pacing rate, 50 pulses per minute). SAS was defined as an apnea-hypopnea index ≥10/h. Mean Epworth Sleepiness Scale was in the normal range (7±4), although 13 patients (25%) had an abnormal score >11/h. Fifty-seven patients (59%) had SAS; of these, 21 (21.4%) had a severe SAS (apnea-hypopnea index >30/h). In patients with heart failure, 50% presented with SAS (mean apnea-hypopnea index, 11±7) compared with 68% of patients with atrioventricular block (mean apnea-hypopnea index, 24±29) and 58% with sinus node disease (mean apnea-hypopnea index, 19±23). Conclusions— In paced patients, there is an excessively high prevalence of undiagnosed SAS (59%). Whether treating SAS would have changed the need for pacing is unknown. Treatment effects should be further evaluated particularly because these patients are less symptomatic than typical SAS patients. In any case, SAS should be systematically searched for in paced patients owing to potential detrimental effects on their cardiovascular evolution.