Prevalence and predictors of atrial arrhythmias in patients with sinus node dysfunction and atrial pacing

This study aimed to determine the incidence, prevalence, and predictors of atrial arrhythmias (AAs) in patients with symptomatic sinus node dysfunction (SND) who required permanent pacemaker implantation. Also, we evaluated the impact of atrial pacing (AP) on AAs.

All consecutive patients who underwent pacemaker implantation from 2005 to 2011 were included. Atrial fibrillation (AF), atrial flutter (AFL), atrial tachycardia (AT), and AV nodal reentrant tachycardia (AVNRT) were detected via pacemaker interrogation and clinical documentation.

The study group included 322 patients (44% male) with mean age 68.8 ± 15 years and followed for an average of 5.6 ± 2.2 years (median 5.7 years). Overall, 61.8% were found to have any AA at follow-up. Individual prevalence of AAs was high as follows: AF 43.5%, AFL 6.5%, AT 25%, and AVNRT 6.8%. AF was documented in 23% of patients (n = 74) prior to pacemaker; among those, 15% (n = 11) had no recurrence of AF with average AP of 74%. The incidence of new-onset AF after pacemaker was 15.8%. In subgroup analysis, prevalence of AF was increased by 16% with high rate of AP (81-100%) and 17% with lower rate of AP (0-20%). Incidence of new-onset AF was not affected by AP. Diabetes, hypertension, and left atrial enlargement were predictors of AAs. White men and women had higher prevalence of AF.

AAs are highly prevalent in SND, particularly in white patients. Paroxysmal AF is suppressed with AP in minority, but there is no impact of AP on new-onset AF. Patients with diabetes, hypertension, and dilated atria must be monitored closely for early detection of AAs.