Performance of a ventricular automatic-capture algorithm in a wide clinical setting.

Background: The optimal programming of a pacemaker (PM) voltage output considers both efficiency (prolonging battery cell longevity) and patient safety (adequate safety margin). Currently, automatic capture (AC) algorithms are designed to ensure safe automatic stimulation threshold determination and pacing with a safety margin.

Methods: The aims of this prospective observational study were (1) to evaluate, over a short-term follow-up, the extent of backup pacing in patients implanted with an AC-featured PM produced by Boston Scientific (Insignia) and a wide range of ventricular leads; (2) to identify patient- or lead-specific predictors of ventricular threshold increase or missed detection of the ventricular pacing threshold; and (3) to analyze day-to-day fluctuations in the ventricular pacing threshold and the relationship between their magnitude, the characteristics of patients, and the system implanted.