Permanent cardiac pacing in pediatrics: experience in Thailand.

Permanent cardiac pacing in pediatrics is uncommon. There has been limited data in Thailand. A retrospective study of cardiac data and pacing parameters during follow-up periods in patients who underwent permanent pacemaker implantation at the Department of Pediatrics, Siriraj Hospital, from January 1997 to December 2004 was conducted. There were 31 patients in total who have been followed-up for the median period of 34.4 (1.07-91.13) months. All patients had atrio-ventricular block prior to implantation. The etiology were; post cardiac surgery 38.7%, maternal autoimmune diseases 19.4%, post radiofrequency ablation 3.2%, and unknown 38.7%. Twenty three cases (74.2%) were implanted by epicardial approach, and 18 (25.8% were implanted by endocardial approach. Modes of permanent pacemaker were WIR 45.2%, VVI 35.5%, and DDD 19.4%. Age and body sized of the patients using epicardial approach were significantly lower than endocardial approach. Minor complications occurred in 3 cases (9.6%) i.e. 2 with surgical wound infection, 1 with post pericardiotomy syndrome. Minimum energy threshold, sensitivity, and impedance at implantation and during follow up periods were not different statistically. There was significantly less in minimum energy threshold of endocardial lead than epicardial lead. Epicardial lead failure was found in 3 cases (11.5%) at the median time of 8.9 (7.9-62) months post implantation, but was not significant different from endocardial leads. Survival of epicardial leads were 82% at 8 years. Conclusion: Permanent pacemaker implantation in pediatrics was rare (4.4 cases/year). It was feasible in almost all body size and a rather safe procedure. There was no significant change in pacing parameters at the medium-term follow-up period for both epicardial and endocardial leads. Minimum energy threshold of epicardial lead was significantly higher than endocardial lead.