abnormal fetal atrioventricular canal morphology abnormal fetal atrioventricular canal septation MPheno.ontology anomaly in the process by which the dorsal and ventral endocardial cushions develop in the walls of the common atrioventricular canal, grow toward each other and fuse, dividing the common atrioventricular canal into right and left atrioventricular canals and the atrioventricular septum abnormal partitioning of the atrioventricular canal 2010-10-06T09:58:37Z csmith MP:0010599