The long-term outcome of children with isolated congenital complete atrioventricular block.

Patients with isolated congenital complete atrioventricular block (CCAVB) may revert to a lower degree of atrioventricular block and do not require pacemaker treatment. The change of rhythm is less well studied in pediatric patients. The aim of this study was to report the long-term outcome of pediatric patients with isolated CCAVB at our institution, with emphasis on restoration of sinus rhythm. We reviewed the medical records of 16 consecutive children with isolated CCAVB at our institution. They were divided into a prenatal group (n=9) and a postnatal group (n=7). In the prenatal group, with follow-up of 28 months (median, range 1-154 months), one patient without symptoms had transient restoration of sinus rhythm and did not require pacemaker therapy, five patients required pacemaker therapy and three of them died, and the remaining three patients without symptoms did not require pacemaker therapy. In the postnatal group, with follow-up of 84 months (median, range 14-133 months), one patient without symptoms had restoration of sinus rhythm and did not require pacemaker therapy, three patients required pacemaker therapy and survived, and the remaining three patients without symptoms did not require pacemaker therapy. Compared to the postnatal group, the prenatal group needed earlier pacing and had higher rate of maternal autoantibodies. There were no significant differences in sex, pacemaker implantation rate, dilated cardiomyopathy, and mortality rate between the two groups. Pacemaker implantation is indicated in most patients with isolated CCAVB, but a change to a lower degree of block can occur in some pediatric patients who may not require pacemaker implantation.