Automatic assessment of atrial pacing threshold in current medical practice.

Aims: The aim of this study was to validate the ambulatory automatic atrial threshold monitoring algorithm by comparing the measurements assessed by the automatic system and those evaluated manually by the physician at discharge, 2- and 8-month follow-up sessions.

Methods And Results: This is an observational multicentric prospective study of 352 patients implanted with EnPulse(®) DR pacemakers. Mean age was 76.3 ± 9.4 years. Indications of pacing were atrio-ventricular block (AVB) (64%) and sinus dysfunction (SD) or brady-tachy syndrome (36%). The automatic atrial threshold monitoring function was maintained at nominal programming state with daily measurement scheduled at 1:00 am. Ambulatory automatic atrial threshold assessment was possible for 91.5% of patients at discharge, 97.3% at 2 months, and 95.7% at 8 months. Causes of the unsuccessful attempts to perform automatic atrial threshold were atrial arrhythmias or permanent atrial and ventricular pacing. Feasibility is significantly better for AVB indication than SD indication due to more frequent occurrence of atrial fibrillation (AF). At each stage, there is a strict correlation between the automatic measurements and those conducted manually by the physician with a P < 0.001.

Conclusion: Feasibility of ambulatory automatic atrial threshold is good. Results of the study show excellent correlation between the two methods for atrial threshold: there is no statistical difference between manual and automatic measurements during follow-up.