Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with relevant morbidity and
mortality. Besides hypertension, valvular disease and cardiomyopathy, mainly ischemic and dilated, also other conditions
like obesity, alcohol abusus, genetic factors and obstructive sleep apnea (OSA) are discussed to contribute to the progression
from paroxysmal to persistent AF. The prevalence of OSA among patients with AF is 40-50%. OSA is characterized
by periodic or complete cessation of effective breathing during sleep due to obstruction of the upper airways. Obstructive
respiratory events result in acute intrathoracic pressure swings and profound changes in blood gases together leading to
atrial stretch and acute sympatho-vagal dysbalance resulting in acute apnea related to electrophysiological and hemodynamic
alterations. Additionally, repetitive obstructive events in patients with OSA may lead to sympathetic and neurohumoral
activation and subsequent structural and functional changes in the atrium creating an arrhythmogenic substrate for
AF in the long run.
This review focuses on the acute and chronic effects of negative thoracic pressure swings, changes in blood pressure and
sympatho-vagal dysbalance induced by obstructive respiratory events on atrial electrophysiology and atrial structure in
patients with obstructive sleep apnea.