Aerial supply to SA node is by:: (A) Left anterior descending coronary aery, (B) Posterior interventricular (descending) aery, (C) Left coronary aery, (D) Right coronary aery
Answer is D. 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.