Capture management efficacy in children and young adults with endocardial and unipolar epicardial systems

Abstract

Aims: This prospective study characterized performance of the Kappa 700 Ventricular Capture Management trade mark (VCM) system for monitoring ventricular pacing threshold and adapting outputs in both endocardial and unipolar epicardial pacing systems in children and young adults. VCM bears cautionary labelling against use with epicardial leads since they have not been demonstrated appropriate for use with VCM.

Methods and results: VCM was programmed in "Monitor Only" mode. Ventricular pacemaker thresholds were measured daily using VCM for a minimum of 2 months. Potential device longevities at nominal outputs (3.5 V, 1.0 ms) and at VCM-recommended outputs were compared. Thirty patients (median age 14.4 years (1-27 years); 15 epicardial/15 endocardial) completed the study. During the daily measurements, consistent undersensed evoked response occurred in 2 patients (Medtronic epicardial leads 4965). For the other 28 patients, programming VCM in "Adaptive" mode from implant would provide an additional 6.8 months (0-19 months) of battery life.

Conclusion: Although not an IDE (Investigation Device Exemption) study, this study showed acceptable VCM performance in "Monitor Only" mode in 13/15 patients with unipolar epicardial leads. A 2-month "Monitor Only" observation period helps screen patients who might not benefit from VCM. VCM may provide substantial energy savings and extended battery life for children and young adults.