Background: Obstructive sleep apnea (OSA) can lead to cardiac complications: brady and tachyarrhythmias and sudden cardiac death. Continuous positive airway pressure (CPAP) is the gold standard for the treatment of OSA. The present study aims to demonstrate the efficiency of CPAP in the treatment of cardiac arrhythmias in patients with OSA. The study also recorded the frequency of arrhythmias in patients with untreated OSA and assessed the association between the severity of OSA and the occurrence of arrhythmias.

Materials and methods: This is a prospective cohort study. Ninety-three patients with OSA were included, aged 60 (58-64) years, with female/male sex ratio of 1:4. They were subjected simultaneously to home respiratory polygraphy examination and Holter electrocardiogram monitoring, in two different stages: at diagnosis and at the 3-month checkup after CPAP treatment. The presence of supraventricular and ventricular arrythmias was noted. Respiratory parameter values were also recorded.

Results: Statistically significant decrease in the occurrence of supraventricular (P < 0.001) and ventricular extrasystoles (P < 0.001), atrial fibrillation (AF) (P = 0.03), nonsustained ventricular tachycardia (NSVT) (P = 0.03), and sinus pauses (P < 0.001) was observed 3 months after treatment with CPAP, compared with baseline. The apnea-hypopnea index (AHI) was correlated with the ventricular extrasystoles (r = 0.273; P = 0.008). The ejection fraction of the left ventricle was inversely correlated with the episodes of NSVT (r = -0.425; P < 0.001). AF was associated with the longest apnea (r = 0.215; P = 0.04). Cardiac activity pauses were correlated with AHI (r = 0.320; P = 0.002), longest apnea (r = 0.345; P = 0.01), and oxygen desaturation index (r = 0.325; P = 0.04).

Conclusion: The prevalence of cardiac arrhythmias in patients with OSA was reduced after 3 months of CPAP therapy. Cardiac arrhythmias were correlated with the severity of OSA.