Clinical and hemodynamic significance of anomalous origin of the right coronary artery from the pulmonary artery.

Anomalous origin of the right coronary artery (RCA) from the pulmonary artery (PA) is very rare, and may be an isolated defect, or associated with other congenital cardiac or non-cardiac defects. The anomalous right coronary artery may appear grossly normal if it arises near an aorto-pulmonary window, and will be perfused by oxygenated blood. However, it may be vein-like and perfused in a retrograde fashion from the left coronary artery (LCA). This was once thought to be a benign lesion, and an incidental finding during cardiac catheterization or surgical repair of the associated congenital cardiac anomaly, but, sudden cardiac deaths have been reported. Associated congenital cardiac defects reported include tetralogy of Fallot (2 cases), aorto-pulmonary window (3 cases), and atrial septal defect (1 case). Another case associated with tetralogy of Fallot is described. Surgical correction of these associated lesions should include anatomical correction of the anomalous right coronary artery.