Three-dimensional volume rendered reconstruction of the coronary anatomy on cardiac computed tomography (left). The sinus node artery (small arrows) originates from the circumflex artery and courses underneath the left atrial appendage before ascending between the left atrial appendage and the left superior pulmonary vein towards the left atrial roof and cavo-atrial junction. Ablation in the superior part of this region (circle) repeatedly resulted in sinus arrest necessitating atrial pacing as shown on the electrocardiogram underneath the 3-dimensional images. LAA: left atrial appendage; LCA: left coronary artery; LSPV/LIPV: left superior/inferior pulmonary vein; RCx: circumflex artery.