Presence and severity of obstructive sleep apnea and remote outcomes of atrial fibrillation ablations — a long-term prospective, cross-sectional cohort study

BACKGROUND: Prior studies suggested that obstructive sleep apnea (OSA) promotes recurrence of arrhythmia in patients after atrial fibrillation (AF) ablation. METHODS: In this prospective, long-term, observational study, we enrolled 290 consecutive patients admitted for AF ablation. Prior to the ablation, all patients underwent a polygraphy sleep study for the diagnosis of OSA. After the procedure, patients were followed up for mean time of 30 months for AF reoccurrence. OSA was diagnosed when apnea-hypopnea index (AHI) was ≥5. Patients were subsequently divided into groups according to the OSA severity: mild OSA (AHI 5-15/h), moderate OSA (AHI >15 and ≤30/h), and severe (AHI >30/h). RESULTS: After excluding patients disqualified from the procedure, and those with central sleep apnea, the study population consisted of 251 patients, mean age 57.6 years [163 (64.9%) male]. OSA was present in 115 (45.8%) patients, while in 137 (54.6%) cases, we observed reoccurrence of AF. Recurrence was more often in patients with, than without, OSA (65.2 vs. 45.6%; p = 0.003). We also observed that along with rising OSA severity rose also the number of patients in whom AF was detected during the follow-up period (45.6 vs. 66.2 vs. 57.6 vs. 81.8%; p = 0.005; for non-OSA, mild, moderate, and severe, respectively). CONCLUSIONS: OSA is highly prevalent in AF patients. The presence of OSA lowers chances on successful AF ablation. Early screening, and treatment for OSA in AF patients, may improve low success rates of AF ablation procedures.