Figure 16a. Anatomic variant of the RCA in a 79-year-old woman who complained of chest pain. (a, b) Coronary CT angiograms clearly show the origin of the RCA from the left coronary sinus by simultaneously demonstrating the LAD artery and the RCA. (c, d) Images reveal that the RCA (arrows) is compressed between the ascending aorta and the right ventricle.