Coronary angiography of the right coronary artery shows the typical location of a branch to the atrioventricular node taking off from the right posterolateral (RPL) branch in the right-dominant coronary circulation. There is some atherosclerotic narrowing in the proximal part of the artery before the take-off of a large acute marginal branch and the right posterior descending branch (RPD). (A higher resolution / colour version of this figure is available in the electronic copy of the article).