The nature and significance of anomalous coronary arteries in tetralogy of Fallot.

Origin of the left anterior descending from the right coronary artery and single coronary artery are the 2 most common coronary artery anomalies associated with tetralogy of Fallot. Their importance relates to their anomalous course over the night ventricular outflow tract where they are subject to inadvertent ligation at the time of right ventriculotomy.The angiographic anatomy of these coronary artery anomalies is illustrated by the 2 cases presented in this report.It is concluded that analysis of the angiocardiograms in tetralogy of Fallot should include evaluation of the coronary arteries, and when there is uncertainty with regard to their origin and distribution, additional selective coronary arteriography should be performed.