The congenital heart block (CHB) is the heart block that is diagnosed in fetus (in utero) or within the first 28 days after birth (neonatal period), some studies also include the diagnosis during early childhood to the definition of CHB. It refers to the disorder in the electrical conduction system within the heart muscle, which leads to the failure in pumping the blood efficiently into the aorta and the pulmonary trunk. The result of CHB can be first, second, or third-degree (complete) atrioventricular block (a block in the atrioventricular node) in which no electric signals move from the atrium to the ventricles