This document discusses various classification systems for congenital heart defects including:
1. The Leiden convention for coronary artery anatomy in transposition of the great arteries (TGA).
2. The Yacoub and Radley-Smith classification for coronary artery patterns in TGA.
3. The Kuhne classification for tricuspid atresia.
4. The Collett-Edwards and Van Praagh classifications for truncus arteriosus.
It then discusses classification systems for defects such as double outlet right ventricle (DORV), single ventricle, total anomalous pulmonary venous connection (TAPVC), interrupted aortic arch, and aortopulmonary window