Figure 1
(A) Nonselective contrast injection in the left coronary sinus does not show the left main coronary artery. (B, C) Selective right coronary artery (RCA) angiograms show orthotopically arising RCA and anomalous origin of the left circumflex artery (thick white arrow) from the ostio-proximal RCA. The left anterior descending artery was not seen in this injection.
Figure 2
Volume-rendered images (A-D) of coronary computed tomography angiography shows normal origin and course of the RCA. Note the anomalous origin of the LCx from the proximal RCA, taking a retroaortic course to reach the left atrioventricular groove. The LAD artery (white arrowhead) is seen arising from the RCS, adjacent to the RCA ostium, taking a pre-aortic, interarterial course (between the aorta and MPA) to reach the anterior interventricular groove. A short axis reconstruction (E) at the level of the aortic root and an oblique sagittal reconstruction (F) demonstrate the unique circumaortic (retroaortic and preaortic) configuration of the left coronary arteries (LCx and LAD arteries respectively). MPA: main pulmonary artery; LCS: left coronary sinus; NCS: non-coronary sinus; RCA: right coronary artery; LAD: left anterior descending; RCS: right coronary sinus; LCx: left circumflex