The direction of blood flow in anomalous left coronary artery arising from the pulmonary artery

An infant with anomalous origin of the left coronary artery from the pulmonary artery is presented, and the problem of the direction of blood flow in the anomalous vessel is discussed. Determinations of arterial pressure and oxygen saturation in the blood of the anomalous artery have demonstrated that the blood in this vessel flowed in a retrograde manner. It is concluded that in this condition oxygenated blood flows from the aorta into the normal right coronary artery and passes through collateral branches into the left coronary artery with ultimate drainage of the blood into the pulmonary artery. Ligation of the anomalous coronary artery with concomitant de-epicardialization appears to be a rational and effective method of therapy. For maximal effectiveness the operation should be performed prior to the onset of irreversible changes, and emphasis is placed upon the importance of early diagnosis and prompt treatment.