Association of atretic left internal mammary graft with internal mammary to pulmonary vasculature fistula: a case series.

Left internal mammary artery (LIMA) graft to pulmonary vasculature (PV) fistula is a rare complication of coronary artery bypass surgery (CABG), with only a handful of cases being reported. The fistula in these cases connects to a distal branch of the pulmonary artery. The etiology of these fistulae is uncertain, but is thought to be related to post surgical injury and inflammation leading to adhesions and neorevascularization.