Continuous positive airway pressure treatment reduces ventricular arrhythmias in obstructive sleep apnea patients with nocturnal dominance of arrhythmias and in those with severe desaturations

Introduction: Continuous positive airway pressure (CPAP) treatment is considered effective in reducing ventricular arrhythmias (VAs) in patients with obstructive sleep apnea (OSA). Objectives: We aimed to assess the influence of this treatment and to identify determinants of antiarrhythmic response. Patients and methods: We included patients with OSA and VAs (corresponding to grades 2–5 in the Lown classification), who underwent CPAP treatment and controls, who refused CPAP therapy. Holter electrocardiographic monitoring was performed at baseline and after 3 months of follow-up. Results: The study consisted of 46 patients in the CPAP group and 30 controls. We observed a significant reduction in premature ventricular contractions (PVCs) and nonsustained ventricular tachycardia events (P = 0.007 and P = 0.03, respectively) in the CPAP group after 3 months, and no difference in controls. The effect of PVC reduction was significant in the patients with nocturnal dominance of PVCs (P = 0.002) and with desaturations equal to or below 80% (P = 0.001). PVC reduction rate (PVC at follow-up / PVC at baseline) correlated inversely with night / day PVC ratio at baseline (R = –0.36; P = 0.02) and the lowest saturation (R = 0.32; P = 0.03) in the CPAP group. After adjustment for clinical data, night / day PVC ratio was an independent predictor of PVC reduction rate (unstandardized coefficient B = –0.19; 95% CI, –0.37 to –0.01; P <⁠0.05). Its value equal to or greater than 1.16 predicted good antiarrhythmic treatment response with sensitivity and specificity of 83% and 70%, respectively. Conclusions: CPAP treatment decreases VAs in OSA patients, especially those with severe desaturations and nocturnal domination of PVCs. Night / day PVC ratio might be a useful clinical parameter predicting reduction of PVCs in these patients.