Giant aneurysmal coronary artery fistula originating from the left circumflex artery: Two case reports.

Coronary artery fistula (CAF) is one of the most common coronary artery anomalies. The most common fistulas originate from the right coronary artery and drain into the right heart structures. Due to the variety of coronary fistulas, the surgical treatment strategy is individualized for each case. We report two cases of giant aneurysmal CAF originating from the left circumflex artery. One case required coronary artery bypass grafting, while the other did not.