The most common congenital cardiac lesion identified at bih is

Ventricular Septal Defect (VSD) This is the most common congenital cardiac lesion identified at bih accounting for one-quaer of all CHD. VSD is a communication between the two ventricles. 90% are located in the membranous pa of the ventricular septum with variable extension into the muscular septum. Others are located in the muscular septum and can be multiple. Reference: Essential Paediatrics; O.P. Ghai; Page no: 414