Abstract 15680: Sinus Node Dysfunction in Associated With Higher Symptom Burden and Increased Risk of Progression to Permanent Atrial Fibrillation: Results From ORBIT-AF Registry

Abstract

Background: Patients with sinus node dysfunction (SND) are at increased risk of atrial tachyarrhythmias, including atrial fibrillation (AF). Whether the presence of SND is also associated with worse outcomes among those with AF has not been well described. Methods: The ORBIT-AF registry enrolled patients with AF from a range of clinical practices across the US. SND was defined clinically, based on the presence of sinus bradycardia, severe sinus bradycardia, sinus arrest, sinoatrial exit block, or features of tachycardia-bradycardia syndrome. Descriptive statistics and multivariable logistic regression analysis were used to describe treatment patterns and outcomes for patients with and without SND and AF. Results: Overall, 1,710 (17.7%) patients had SND at enrollment. Patients with SND had lower left-ventricular ejection fractions, higher CHA 2 DS 2 -VASc risk scores, and more prior cerebrovascular events. Patients with SND had more severe symptoms (EHRA class IV: 17.5% vs. 13.9%; p=0.007) and poorer quality of life (median AFEQT 77.5 vs. 81.1; p=0.008) as compared to those without. SND patients were more frequently treated with oral anticoagulants (79.2% vs. 75.9%, p=0.004) and had more often received interventional therapy for AF (16.1% vs. 10.5%, p<0.0001). There were no differences in the current AF management strategy between patients with SND and those without [rate control (69.7% vs. 67.7%), rhythm control (30.0% vs. 32.0%); P=0.11]. After adjustment, significantly more patients with SND had progressed from paroxysmal AF at baseline to persistent or permanent AF at any follow-up or persistent AF at baseline to permanent AF at any follow-up than those without (OR 1.23, 95% CI 1.01-1.49, p=0.035). Conclusion: Sinus node dysfunction is associated worse symptoms, lower quality of life, and higher risk of progression to permanent AF. However, SND is not associated with increased risk of all-cause hospitalization, incident stroke, or all-cause death.