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A 74 year-old man presents to the clinic with a complaint of palpitation and lightheadedness. Image studies revealed blockage of the artery to the SA node.
This artery arises from which of these arteries?
A-Left coronary artery
B-Right coronary artery
C- Circumflex artery
D-Anterior interventricular artery
E-Posterior interventricular artery
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I would just like to add to this question. The SA node is always supplied by the RCA however the AV node gets its supply from a branch of PCA which in turn is a derived from RCA in majority (over 80%) of the people. However if the question clearly mentions that a person's heart has a LEFT DOMINANT arterial supply, the AV node in such a person's heart which receive its blood supply from the LCA.
So in summary, SA node always gets its blood supply from the RCA
AV node in majority of the casesgets its supply from the RCA but in left dominant circulation, the AV node is supplied by the LCA.
 
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