Congenital Absence of Left Circumflex Coronary Artery: Circumflex Artery Extended from Right Coronary Artery

Nonvisualization of left circumflex coronary artery from the left coronary artery is commonly due to anomalous origin of circumflex artery from the right coronary artery or right sinus of Valsalva. However, complete ostial obstruction of circumflex artery, circumflex artery extended from the right coronary artery, anomalous origin of circumflex artery from the pulmonary artery may be the cause. We report two cases of absent left circumflex artery from the left coronary artery, in which the circumflex artery arose as a terminal extension of the right coronary artery. Angiographic features of absent left circumflex artery from the left coronary artery were described.