This report describes the case of a man who presented with fever, weight loss, and Streptococcus mitis septicemia. He was found to have congenital bilateral coronary artery fistula, a rare condition. There was no evidence of vegetation on the heart valves on transthoracic or transesophageal echocardiography. Instead, transesophageal echocardiography showed vegetation within the coronary sinus near its entrance into the right atrium. Coronary angiography confirmed the presence of a left circumflex artery to coronary sinus fistula and a right coronary artery to coronary sinus fistula. To the authors' knowledge this combination of findings has never been reported before.