Long-Term Outcome of Isolated Congenital Complete Atrioventricular Block Pacing Since Neonatal Period Experience at a Single Japanese Institution

BACKGROUND: Few investigators have examined the outcome of patients with isolated congenital complete atrioventricular block (CCAVB) paced from the neonatal period. The present study follows the clinical course and describes the outcome of patients who have been paced with CCAVB since they were neonates. METHODS AND RESULTS: The medical records of 20 patients with CCAVB paced as neonates between 1981 and 2006 were retrospectively studied and reviewed; 18 were diagnosed in utero and 2 at birth. SS-A antibodies were detected in 9 of 14 (64%) mothers tested. The median age at follow-up was 5.6 years (range, 2 days to 21.9 years). Three (15%) of the early neonates died and 3 (15%) died later: 2 from dilated cardiomyopathy (DCM) and 1 from pneumonia. The total mortality rate was 30%. The cumulative probability of survival at 10 years was 73%. Of the 14 survivors, 4 developed DCM, representing a total morbidity of 30%. The cumulative probability of freedom from DCM at 10 years was 59%. CONCLUSIONS: Patients with CCAVB who undergo pacing as neonates have high mortality and high morbidity because of DCM. Left ventricular pacing or resynchronization can benefit patients who develop DCM and left ventricular epicardial pacing is recommended for neonates with CCAVB.