Abstract 17824: Nocturnal Intermittent Hypoxia is Associated With Reduced Left Atrial Appendage Function in Atrial Fibrillation
Background: Sleep-disordered breathing (SDB) is closely related to stroke and atrial fibrillation (AF), however the mechanism of these associations is not well established. We assessed the hypothesis that SDB could be associated with reduced left atrial appendage (LAA) function as well as spontaneous echo contrast development in patients with AF.
Methods and Results: Consecutive 134 AF patients (age, 59.6 ± 9.4 years; body mass index [BMI], 24.8 ± 3.2; CHADS2 score, 0.7 ± 0.9; CHA2DS2-VASc score, 1.2 ± 1.1, paroxysmal AF, n = 83) who were candidates for catheter ablation were evaluated. We used a nocturnal pulse oximetry as a non-invasive screening method for nocturnal intermittent hypoxia, a surrogate marker of SDB. Nocturnal intermittent hypoxia was evaluated using 3% oxygen desaturation index (3% ODI) which was the number of oxygen desaturation measurement ≤ 3% per hour, and we divided the patients into nocturnal intermittent hypoxia group (3% ODI>15; n =32) and control group (3% ODI<15; n =102). Nocturnal intermittent hypoxia group had significantly higher weight, BMI, CHADS2 and CHA2DS2-VASc scores, serum HbA1c and plasma BNP level, and left atrial size (all p<0.05). The prevalence of hypertension, vascular disease, and sick sinus syndrome was also higher in nocturnal intermittent hypoxia group (all p<0.05). Among paroxysmal AF patients, the incidence of nocturnal AF attacks was not different between two groups. Transesophageal echocardiography (TEE) data showed that nocturnal intermittent hypoxia was associated with a higher grade of spontaneous echo contrast and lower LAA flow velocity (all p<0.05). The multiple regression analysis adjusted by the type of AF (odds ratio [OR] = -0.313; p=0.002; 95% confidence interval [CI], -19.816 to -4.590), CHA2DS2-VASc score (p=0.423), BMI (p=0.553), plasma BNP level (p=0.209), left atrial size (p=0.159), and rhythm during TEE (p=0.510) revealed that 3% ODI was the independent risk factor for the LAA flow velocity (OR = -0.184; p=0.047; 95% CI, -0.818 to -0.006).
Conclusions: Nocturnal intermittent hypoxia was highly prevalent among AF patients and was an independent determinant for reduced LAA flow velocity, suggesting that SDB might be associated with cardiogenic stroke through reduced LAA function.
Author Disclosures: T. Kimura: None. T. Kohno: None. S. Kashimura: None. Y. Katsumata: None. T. Nishiyama: None. N. Nishiyama: None. Y. Tanimoto: None. Y. Aizawa: None. K. Fukuda: None. S. Takatsuki: None.
- © 2014 by American Heart Association, Inc.