title: Energy-conserving programming of VVI pacemakers: a telemetry-supported, long-term, follow-up study.
abstract: Thirty patients with VVI pacemakers (Quantum 253-09, 253-19, Intermedics Inc., Freeport, TX) were observed for a mean of 65 months. Within 12 months after implantation, optimized output programming was performed in 29 patients. This included a decrease in pulse amplitude (22 patients), pulse width (4 patients), and/or pacing rate (11 patients). After 65 months postimplantation, telemetered battery voltage and battery impedance were compared with the predicted values expected when the pulse generator constantly stimulates at nominal program conditions (heart rate 72.3 beats/min, pulse amplitude 5.4 V, pulse width 0.61 ms). Instead of an expected cell voltage of 2.6 V and a cell impedance of 10 k omega mean telemetered values amounted to 2.78 V and 1.4 k omega, respectively. These data correspond to a battery age of 12-15 months at nominal program conditions. This long-term follow-up study suggests that adequate programming will extend battery longevity and thus pulse generator survival in many patients.
authors.affiliation: Department of Cardiology, University of Göttingen, Federal Republic of Germany.
authors.forename: H H
authors.initials: HH
authors.lastname: Klein
authors.forename: W
authors.initials: W
authors.lastname: Knake
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000628:therapy; D003246:Conservation of Energy Resources / Q000379:methods; D004553:Electric Conductivity; D011211:Electric Power Supplies / Q000592:standards*; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D012984:Software / Q000592:standards; D013686:Telemetry; D013813:Therapy, Computer-Assisted / Q000592:standards*