Twin left circumflex arteries in a patient undergoing aortic valve replacement.

We present the case of a patient with severe symptomatic aortic valve (AV) stenosis in whom preoperative coronary angiography revealed two separate left circumflex (LCx) arteries, one arising from the left main coronary artery and the other from the right aortic sinus following thereafter a retroaortic course to the left. The pattern of LCx artery anatomy revealed was recognized as one of bilaterally arising twin LCx arteries that is a rare coronary anomaly with only 7 reported cases in the English literature. We discuss the importance of preoperative identification of this anomaly in patients undergoing AV surgery and describe simple clues in order to easily identify it.