Aerial supply to SA node is by:
The right coronary aery arises from the anterior aoic sinus of the ascending aoa and runs forward between the pulmonary trunk and the right auricle.The aery of the sinuatrial node (branch of right coronary aery) supplies the SA node and the right and left atria; in 40% of individuals it arises from the left coronary aery.
Left anterior descending coronary aery
Posterior interventricular (descending) aery
Left coronary aery
Right coronary aery