We present the case of 15-year-old asymptomatic girl referred to our institutionwith the diagnosis of mitral valve prolapse and a suspicion of coronary artery fistula. Detailed diagnosticsrevealed Bland-White-Garland syndrome (B-W-G) with tortuous aneurysmatic right coronary artery (9 mmin diameter). In addition, on surgery, multiple collateral vessels between the right and left coronaryarteries were found crossing over the pulmonary trunk and right ventricle. Because of fragile and calcifiedanterior walls of the main pulmonary artery we had to elect Hamilton rather than Takeuchi technique.The procedure was aggravated by continuous blood outflow from enlarged LCA ostium suggesting systemiccollateral supply. Weaning from cardiopulmonary bypass and postoperative period was uneventful. Thereare only two published reports on systemic collateral supply to LCA in patients with BWG.

Keywords: Cardiopulmonary Bypass, Coronary Artery Anomalies, collateral blood supply