Classification of VSD
The commonest variety of ventricular septal defects are the perimembranous VSDs which account for about seventy to eighty percent of the ventricular septal defects. Muscular VSDs contribute about five to twenty percent of the total VSDs. Muscular VSDs could be central/mid muscular, apical, marginal along the right ventricular septal junction and Swiss cheese septum with multiple defects. Inlet/AV canal type of VSDs contribute about five to eight percent and supracristal/subaortic another five to seven percent.