Congenital heart diseases (CHDs) are conditions that arise during a baby's development in the womb. These diseases, observable in the fetal period, include structural anomalies such as ventricular septal defect (VSD), heart valve stenoses, atrial septal defect (ASD), transposition of the great arteries (TGA), and patent ductus arteriosus (PDA). Additionally, secondary cardiac conditions can develop, where the heart is indirectly affected by non-cardiac factors like various rhythm disturbances or anemia.