Circumflex ramus originating from right sinus of Valsalva with further posterior vessel course (Subgroup 4d). This case shows an abnormal origin of LCX from the right sinus of Valsalva with a further posterior (retroaortic) course of LCX within the atrioventricular groove (Image A, Volume Rendering Technique, posterior view). Cross-sectional curved Multiplane Reformats nicely depict the anatomic relationships of the vessel, left atrium and Aorta (Images B). In Image B2 the retroaortic course within the atrioventricular groove of LCX is marked with a black arrow. LCX: left circumflex ramus; LA: left atrium; LAD: left anterior descending coronary artery; LVOT: left ventricular outflow tract; RCA: right coronary artery; RSV: right sinus of Valsalva.