abnormal heart right atrium morphology abnormal vena cava sinus morphology 2010-09-30T01:19:16Z MP:0010497 MPheno.ontology abnormal sinus of the vena cava any structural anomaly of the portion of the cavity of the right atrium of the heart that receives the blood from the vena cavae and is separated from the rest of the atrium by the crista terminalis csmith