Q..In case of posterior interventricular artery arising from circumflex artery -what is true of coronary circulation, a.it is right dominant circulation b.it is left dominant circulation c.codominant circulation d. ans. ref:Clinically oriented Anatomy 5/E,Keith.l.Moore;pg.159. Variations of the Coronary Arteries -Variations in the branching patterns and distribution of the coronary arteries are common. In the most common right dominant pattern, present in approximately 67% of people, the RCA and LCA share about equally in the blood supply of the heart. -In approximately 15% of hearts, the LCA is dominant in that the posterior IV branch is a branch of the circumflex artery,this' LEFT DOMONANCE'. -There is codominance in approximately 18% of people, in which branches of both the right and left coronary arteries reach the crux and give rise to branches that course in or near the posterior IV groove. -A few people have only a single coronary artery. -In other people, the circumflex branch arises from the right aortic sinus. - Approximately 4% of people have an accessory coronary artery. -so i guess the right ans shud be choice B.