Study of heart rate variability in children with pacemaker

Abstract

Heart rate variability (HRV) evaluates the autonomic modulat ion on sinus node and is age-related in children. In pediatric patients (pts), permanent pacing is performed by W l R and DDD pacemakers (PM) according to pts age, Aim of the study is to compare heart rate (HR) and HRV in pts with W l R (activity sensor) and DDD PM for congenital or post-surgical complete A-V block and in age-matched controls. Children were divided in 4 groups: I, 16 pts with W I R PM; II, 51 controls; III, 10 pts with DDD; IV, 51 controls. All children underwent echocardiography that showed normal ventricular dimensions and function in all children, and 24-hour Holter monitoring to evaluate mean, max and rain HR and t ime-domain indexes of HRV (sdnn, sdnni, sdann) in the whole registration and, only dunng wake hours, in groups I-A (5 pts with W I R PM) and II-A (6 controls). Statistical analysis was performed by t test (p<0.05 significant) in age-matched groups. W I R PMs were programmed with rain HR 76+7 bpm, max HR 168+13 bpm, activity parameters at medium values; DDD PMs rain. HR 67+17 bpm e max. tracking rate 163+9 bpm. * : p<0.05. Group ~g© C.l's) m¢~nHR max HR rain HR sdnn ms sdnni s~ln I 6.h~2.2 g5¢12 145:[27' 72d:7 ~ 103-22 ~ 50~x22 ° g~.22 II 6.0~.7 94±13' 175:E23' 54±7* 126~237 * 72:~31 1014-98 * III 13.7:1:4.0 73t6 145+37 61±11 131-52 79233 99'248 IV 14.3:L2.2 77::1:9 157±18 45:,£5* 176~43 8 9 ~ 0 150£'43 I-A 7.4+3.0 82~12 137:t33' 71:1:5 95±4t 51:1:35 725:24 II-A 5.8~.2 9 fr2:l 2 183±13' 55±7 98:~2 66+-22 7 I:Y~25 Dudng night, parasympathetic tone and HRV normally increase, while in PM pts, HR stabilises at the programmed HR reducing HRV. Dudng wake hours, when the activity sensor is stimulated, W l R PMs show a physiological pattern of HRV. TRANSVENOUS DUAL CHAMBER PACING IN CHILDREN: CAN PACEMAKER LIFETIME BE EXTENDED W'rH THE USE OF AUTOCAPTURE ~ AND STEROID ELUTING SCREW-IN LEADS? L. Binner, T. Brummer, R. Jungwidh ~, C. Galm ~, D. Lang t, V. Hombach Internal Medicine II-Cardiology and (1) Division of Pediatric Cardiology, University of UIm, Germany