From an LAO perspective, the left anterior descending artery and right posterior descending artery run vertically while the coronary septum loop is seen edge-on and the AV groove loop is seen face-on, with the right coronary artery forming a "C" and the circumflex forming a backwards "C". From the RAO projection, the anterior and posterior descending coronaries run from the base of the heart left to the apex right, while the circumflex and right coronary arteries run vertically parallel to the loop they form at the heart base.

1. Viewed from an LAO perspective, the anterior (LAD) and posterior (RPD) descendings run from top to bottom of the image, and the loop of the septum is seen edge-on. The AV groove loop is opened and seen face-on; the right coronary artery (RCA) forms a “C,” and the circumflex coronary (LCx) forms a backwards “C.”

2. Viewed from the RAO projection, the anterior and posterior descending coronaries course from the base of the heart on the left of the image, towards the apex of the heart on the right of the image, while the left circumflex and right coronary arteries are captured running from top to bottom of the image, more or less in parallel with the loop they define at the base of the heart. (LM=left main coronary; LAD=left anterior descending; LADD=diagonal branches; LCx=left circumflex; CM=marginal branches; LPL=left posterolateral branch; RCA=right coronary artery; RVB=right ventricular branch; AcM=acute marginal branch; RPDA=right posterior descending; RPL=right posterolateral branch.)