Abstract 18428: Effect of Continuous Positive Airway Pressure on Atrial Remodeling in Patients With Obstructive Sleep Apnea and Paroxysmal Atrial Fibrillation; a Randomized Controlled Trial

Abstract

Introduction: Obstructive sleep apnea (OSA) is known to cause left atrial (LA) remodeling. The effect of continuous positive airway pressure (CPAP) on LA remodeling in patients with OSA and paroxysmal atrial fibrillation (AF) has not been assessed. Hypothesis: We aimed to assess the impact of CPAP treatment on reverse LA deformation and volume in patients with AF and OSA. Methods: In this secondary analysis of a prospective randomized controlled trial, we screened patients with AF for OSA. The majority of patients were referred for pulmonary vein isolation (PVI). We included AF patients with OSA defined as apnea-hypopnea index (AHI) > 15/h. Patients were randomized to CPAP treatment or standard care. Transthoracic echocardiography was performed to assess atrial remodeling by two-dimensional speckle tracking LA reservoir strain (by AFI LA) and LA volume index (LAVI) in apical 2- and 4-chamber views in sinus rhythm at baseline and at 12 months’ follow-up by an investigator blinded to allocated arm. AF burden was monitored by an implantable loop recorder in all patients. Results: We included 104 patients (62 ±7 years old, 77% men, BMI 30 ± 4) of whom 50 were randomized to CPAP and 54 to standard care. PVI was performed in 83 patients six months after the baseline exam. There was no clear improvement in LA reservoir strain in either group from baseline to follow up (CPAP: 30 ± 8 % vs 32 ± 9 %, p = 0.15; standard care: 28 ± 7 % vs 30 ± 6 %, p = 0.11), and there was no difference between the groups (p=0.41). Similarly, LAVI did not change in the CPAP group (38±8 mL/m 2 vs 36± 10ml/m 2 , p= 0.16) or in the standard care group (39± 10 mL/m 2 vs 37 ± 12 ml/m 2 , p= 0.20) during follow-up, with no difference between the two groups (p =0.62). In patients who underwent PVI, the AF burden decreased in both treatment arms, with no between-group difference (p = 0.69). Conclusions: In AF patients with OSA, treatment with CPAP did not improve reverse left atrial remodeling within 12 months. Although the trial was relatively small, these results suggest that CPAP is unlikely to have a major impact on normalization of LA function after atrial fibrillation ablation in this patient group.