In 3.0 cm CVRL foetal heart, the two conspicuous masses of loosely organized mesenchymal tissue called endocardial cushions developed (Figure 3) in dorsal and ventral wall of
atrioventricular canal. In 7.6 cm CVRL foetus the dorsal and ventral endocardial cushions met andoccludedthe centralpartofthe canal and separateditinto right and left
atrioventricular canals.
The
atrioventricular canal is an essential structure for separating atrial and ventricular blood flow.
CHD children with congenital rubella infection may have open arterial duct, transposition of great vessels, common arterial trunk, atresia or malformations of atrioventricular and semilunar valve, open
atrioventricular canal, Fallot's tetralogy (5-10% of all CHD), IVSD (5%), stenosis of pulmonary artery (Babajanov et al., 1996; Belacon and Podzaicov, 1991; Popov, 2004; Ulitskiy and Chukhovina, 2001).
Of the structural cardiac abnormalities, 26% were complex cardiac defects, 26% were septal defects only, 19% were left or right hypoplastic heart, 15% were conotruncal abnormalities, 6% were defects of the
atrioventricular canal, and 9% were classified as "other" defects.
The contribution of the inferior endocardial cushion of the
atrioventricular canal to cardiac septation and to the development of the atrioventricular valves: study in the chick embryo.
Common Congenital Heart Disease Terminology AS Aortic Stenosis ASD Atrial Septal Defect AVC
Atrioventricular Canal Defect (same as ECD) CHD Congenital Heart Disease CHF Congestive Heart Failure DORV Double Outlet Right Ventricle ECD Endocardial Cushion Defect (same as AVC) HLHS Hypoplastic Left Heart Syndrome PA Pulmonary Atresia PDA Patent Ductus Arteriosus PGE Prostaglandin E PS Pulmonary Stenosis TGA Transposition of the Great Arteries (or great vessels) TOF Tetralogy of Fallot VSD Ventricular Septal Defect Increased Pulmonary Blood Flow
Bradley has Down syndrome and underwent heart surgery at 6 months of age to correct an
atrioventricular canal defect.
Partial Atrioventricular septal defect is a congenital malformation of
atrioventricular canal with crescent shaped atrial septal defect above the AV valve but no ventricular septal defect below this valve and have two separate right and left AV valves with cleft in left AV valve.
Accounting for approximately 63% of all DS-CHD, their lesion varies in severity from persistent of the common
atrioventricular canal and membranous ventricular septal defects to ostium primum patency with valvular anomalies.
