Congenital anastomosis between left anterior mammary and pulmonary vasculatures.

Several case reports have described the presence of acquired fistula connecting the left internal mammary artery to the pulmonary vasculature; however, occurrence of this type of congenital fistulas is less common. The authors present a case of a congenital left internal mammary artery-pulmonary vasculature fistula that was incidentally found during a coronary angiography in a patient who was being evaluated for coronary artery bypass surgery. The particulars of the case are discussed, and the literature is reviewed.