Utility of preoperative Holter monitoring in children undergoing extracardiac conduit Fontan operation.

BACKGROUND: In patients undergoing extracardiac conduit Fontan (ECF) who require postoperative pacing, epicardial leads are usually required because of anatomical constraints. If indicated, these could be conveniently placed at the time of ECF. We have routinely performed ambulatory 24-hour Holter monitoring before ECF to determine the presence or absence of preoperative sinus node dysfunction, in an attempt to avoid repeat sternotomy at a later time.

METHODS: We performed a retrospective study of all patients undergoing ECF from January 2000 to December 2015.

RESULTS: Two hundred sixteen patients met inclusion criteria. Patients were separated into two groups, those with preoperative Holter monitoring (PHM, n = 150) and those without (No-PHM, n = 66). Ten patients (4.6%) underwent permanent pacemaker implantation at the time of ECF (eight patients [5.3%] in PHM vs two patients [3.0%] in No-PHM, P = 0.46). There were seven (3.2%) patients who underwent pacemaker implantation after ECF requiring repeat sternotomy (four patients [2.7%] in PHM vs three patients [4.5%] in No-PHM, P = 0.47). Fourteen (6.5%) patients underwent permanent epicardial lead placement without a pulse generator at the time of ECF. None from this group underwent pacemaker implantation to date (median follow-up of 5.7 years). The overall incidence of pacemaker implantation was 9.3% (20 patients).

CONCLUSIONS: In our series, arrhythmia disturbances requiring pacing after ECF occurred in just over 9% of patients. While PHM in those patients may help predict which patients might require postoperative pacing, this approach did not result in a significant decrease in those patients requiring repeat sternotomy for pacemaker implantation.