abnormal conotruncus morphology abnormal conotruncus septation csmith anomaly in the process in which the conotruncus separates into the conus cordis, which will give rise to the outflow regions of the ventricles, and the truncus arteriosus which will be divided into proximal ends of the ascending aorta and pulmonary trunk MPheno.ontology 2010-10-05T02:16:30Z MP:0010584 abnormal conotruncal septation