a1 Department of Paediatrics, Caritas Krankenhaus, Bad Mergentheim, Germany
Objectives Potential side effects of stimulants for attention deficit disorder are in the focus of scientific discussions, intensified by the higher number of prescriptions. Children with known arrhythmias or other severe cardiac problems should not receive stimulants because of their sympathomimetic effects.
Methods This is a retrospective analysis of 24-hour Holter electrocardiograms from 100 consecutive children with attention deficit disorder from January, 2006 to April, 2012.
Results In all, nine children had significant ventricular arrhythmia (mean age 11.4 ± 3.1 years, 77% male, 77% received methylphenidate). All these children had ventricular parasystole – four of them with an accelerated idioventricular rhythm. A significant circadian rhythm of premature ventricular contractions in seven children and the effect of standing and exercise clearly indicate the influence of the autonomic nervous system. In these children, hourly analysis of circadian rhythm within a 24-hour period showed a highly significant correlation between premature ventricular contractions and the vagal tone indicated by the heart rate variability parameter RMSSD (r = −0.83; p < 0.001). Ventricular arrhythmia was unaffected in seven children who received methylphenidate before diagnosis and decreased during metoprolol treatment in two children.
Conclusion By Holter electrocardiogram analysis, we observed a remarkably high incidence of ventricular parasystole and accelerated idioventricular rhythm in nine of 100 children with attention deficit disorder, which depends on autonomic imbalance and not on stimulant treatment.
(Received October 05 2012)
(Accepted December 16 2012)
(Online publication February 12 2013)
c1 Correspondence to: Prof. Dr. Reiner Buchhorn, Department of Paediatrics, Caritas Krankenhaus, Klinik für Kinder- und Jugendmedizin, Uhlandstr. 7, 97980 Bad Mergentheim, Germany. Tel: +49-7931-582301; Fax: +49-7931-582390; E-mail: firstname.lastname@example.org