Abstract
Coronary artery fistula (CAF) is a rare entity. Sometimes it may associate with mild diffuse or segmental coronary ectasia. CAF with giant coronary artery is exceptionally rare. We present a unique case of a 49-year-old female patient with a giant right coronary artery of diffuse ectasia coexisting with a fistula draining into the right ventricle. To our best knowledge, CAF with diffuse coronary ectasia of such giant size has never been reported. The patient was treated successfully by resection of the dilated right coronary artery, fistula closure, and coronary artery bypass grafting.