Obstructive Sleep Apnea and Arrhythmia: A Narrative Review of Arrhythmogenic Mechanisms.

Obstructive sleep apnea (OSA) constitutes a chronic disorder characterized by recurrent upper airway collapse during sleep. This condition is prevalent among patients with cardiac rhythm disturbances and represents a potent independent risk factor for arrhythmia. Although most studies have concentrated on the association between OSA and atrial fibrillation (AF), numerous investigations have established connections with ventricular and supraventricular arrhythmias. Arrhythmogenesis in OSA represents a complex multifactorial phenomenon. Acute mechanisms involve induction of negative intrathoracic pressure during the effort to breathe, which triggers recurrent episodes of hypoxia, hypercapnia, alterations in carbon dioxide and acid-base equilibrium, as well as surges in sympathetic nervous system activity. Chronic intermittent hypoxia (CIH) and negative thoracic pressure (NTP) induce atrial stretch, chronic structural remodeling, and elevated vagal tone, thereby heightening susceptibility to bradycardic and conduction arrhythmias. Intermediate pathways through which OSA may precipitate arrhythmia encompass heightened systemic inflammation, oxidative stress, a prothrombotic state, and vascular dysfunction. Long-term OSA is linked with atrial enlargement and fibrosis, ventricular hypertrophy, hypertension, and coronary artery disease. These factors predispose to cardiac arrhythmias through the following mechanisms: shortening of the atrial effective refractory period, abnormal automaticity, promotion of slowed and heterogeneous conduction, enhancement of reentrant arrhythmia persistence, and prolongation of the QT interval. In this paper, we aim to present the pathophysiological mechanisms underpinning the association between obstructive sleep apnea and cardiac arrhythmias. Understanding the precise pathophysiological pathways by which obstructive sleep apnea contributes to arrhythmogenesis will enable targeted preventive stratification of patients at risk for cardiovascular events and promote the development of innovative therapies to attenuate OSA-induced arrhythmogenicity.