A 12-year-old boy with double inlet left ventricle, concordant ventriculoarterial connections, and valvar pulmonary stenosis was palliated in infancy by construction bilaterally of systemic-to-pulmonary arterial shunts and, at 10 years of age, a right cavopulmonary anastomosis. During cardiac catheterization prior to completion of his Fontan circulation, selective injection into the left brachiocephalic vein (Fig. 1) revealed a small left superior caval vein (LSCV), a blind-ending coronary sinus (arrow), and dilated coronary veins. The right superior caval vein (RSCV), and the right and left pulmonary arteries were also opacified. Retrospective review of previous investigations showed that the anomaly had been present from birth.

Figure 1.

Atresia of the orifice of the coronary sinus is uncommon in the setting of persistence of the left superior caval vein, albeit it may occur with or without other associated cardiac anomalies. With this arrangement, the persisting caval vein serves to permit the egress of blood returning to the coronary sinus from the coronary veins.¹ Ligation of the caval vein, therefore, may cause myocardial infarction by increasing coronary venous pressure. In the absence of a levoatrial cardinal vein with an intact atrial septum, or anomalous pulmonary venous connection to the persisting caval vein, the diagnosis is suggested by reversal of flow in the persisting caval vein on Doppler interrogation. Angiography, as shown here, demonstrates a blind-ending coronary sinus, dilated coronary veins, and the persisting caval vein. When contemplating ligation or division of the persisting caval vein in procedures such as a cavopulmonary connection, it is essential to be aware of this unusual malformation, and to unroof the coronary sinus if the vein is ligated.¹ Only rarely will the anomaly be recognized, as in this case, after apparently successful cavopulmonary surgery.