CONGENITAL COMPLETE ATRIOVENTRICULAR-BLOCK

Medical history and recent knowledge on definition, diagnosis, etiolog y, natural history, and management of congenital complete atrioventric ular block (CCAVB) are reviewed. An association between material conne ctive tissue disease and most cases of CCAVB has been demonstrated, bu t further and more specific proof of a causal relationship is needed. Mortality and morbidity in isolated CCAVB is highest in fetal life and in the neonatal period, but is also considerable in infancy, childhoo d, and adult life. The presence of associated structural heart disease and/or significant endomyocardial fibrosis increases the mortality an d morbidity. Treatment of CCAVB is possible and effective in most case s, and prevention might be possible in selected cases in the near futu re. The low complication rate of pacemaker treatment of today justifie s a generous attitude toward treatment. The risk of sudden death in ad ult life without prodromal symptoms, the gradually decreasing ventricu lar rate, and a high incidence of 'acquired' mitral insufficiency are arguments in favor of prophylactic pacemaker treatment.