DO_rare_slim has major susceptibility factor disease has location atrioventricular septal defect MESH:D004694 ORDO:98722 DOID:0050651 A congenital heart septal defect characterized by an abnormal or inadequate fusion of the superior and inferior endocardial cushions with the mid portion of the atrial septum and the muscular portion of the ventricular septum, thus allowing extra blood to circulate the lungs. GARD:802 ICD10CM:Q21.2 SNOMEDCT_US_2025_09_01:204322008 AVCD MIM:614474 MIM:614430 disease_ontology AVSD MIM:606215 ECD ICD9CM:745.6 UMLS_CUI:C0014116 Xref MGI. OMIM mapping confirmed by DO. [SN]. atrioventricular canal defect endocardial cushion defect heart disease heart septal defect susceptibility to atrioventricular septal defect 2 atrioventricular septum