Permanent single chamber atrial pacing: obsolete or a viable alternative to dual-chamber in selected patients with sinus node disease?

Abstract

Introduction: Single atrial stimulation (AAI) was commonly used for permanent pacing in sick sinus syndrome and significant bradycardia.

Objective: This study aimed to evaluate the long-term AAI pacing and identify the timing and reasons for pacing mode change.

Patients and methods: Retrospectively, we included 207 patients (60% female) with initial AAI pacing, who were followed up for an average of 12 years.

Results: At the time of death or loss to follow-up, 71 (34.3%) patients had unchanged AAI pacing mode. The reason for an upgrade of the pacing system was the development of atrial fibrillation (AF) in 43 (20.78%) and atrioventricular block (AVB) in 34 (16.4%). The cumulative ratio for a pacemaker upgrade reoperation reached 2.77 per 100 patient-years of follow-up. Cumulative ventricular pacing of <10% after an upgrade to DDD was observed in 28.6% of patients. Younger age at implant was the leading independent predictor for the change to dual-chamber simulation (Hazard ratio: 1.98, 95% confidence interval = 1.976-1.988 P=0.001). There were 11 (5%) lead malfunctions that required reoperation. Subclavian vein occlusion was noted in 9 (11%) upgrade procedures. One cardiac device-related infection was observed.

Conclusions: The reliability of AAI pacing decreases with each year of observation due to the development of AF and AVB. However, in the current era of effective AF treatment, the advantages of AAI pacemakers, such as lower incidence of lead malfunction, venous occlusion, and infection compared to dual chamber pacemakers may cause AAI pacemakers to be seen in a different light.