Relation of the Severity of Obstructive Sleep Apnea in Response to Anti-Arrhythmic Drugs in Patients With Atrial Fibrillation or Atrial Flutter

Atrial fibrillation (AF) is more common in those with obstructive sleep apnea (USA) than in unaffected subjects and recurs more frequently in the presence of severe USA after electrical cardioversion and AF ablation. However, it is unknown whether the severity of USA influences the efficacy of antiarrhythmic drug (AAD) therapy in patients with USA and AF. The aim of this study was to examine the impact of USA severity on the treatment of patients with symptomatic AF using AADs. Sixty-one patients (mean age 62 +/- 15 years, 21 women) treated with AADs for symptomatic AF who underwent overnight polysomnography were studied. Rhythm control was prospectively defined as successful if a patient remained on the same AAD therapy for >= 6 months with >= 75% reduction in symptomatic AF burden. Twenty-four patients (40%) had severe USA. Thirty patients (49%) were rhythm controlled with AADs. Nonresponders to AADs were more likely to have severe USA than milder disease (52% vs 23%, p < 0.05); those with severe USA were less likely to respond to AADs than participants with nonsevere USA (39% vs 70%, p = 0.02). Nonresponders had higher apnea-hypopnea indexes than responders (34 +/- 25 vs 22 +/- 18 events/hour, p = 0.05), but there were no differences between these groups in minimum oxygen saturation or percentage of time spent in rapid eye movement sleep. In conclusion, patients with severe USA are less likely to respond to AAD therapy for AF than those with milder forms of USA. (C) 2012 Elsevier Inc. All rights reserved. (Am J Cardiol 2012;110:369-372)