Background Coronary artery fistulas (CAFs) are rare congenital abnormality often unintentionally found in patients with coronary artery disease.Clinical diagnosis of CAFs is difficult due to symptomless or lack of specific symptoms.Dual-source computed tomography (DSCT) might be a useful diagnostic tool for CAFs.The study aimed to retrospectively summarize the imaging features of CAFs delineated at DSCT in 48 CAF patients detected from consecutive 6624 patients with suspected or confirmed coronary artery disease in our institution.Methods Forty-eight patients underwent DSCT angiography by using retrospective electrocardiographic (ECG) gating after infusion of 70 ml of intravenous contrast material during breath hold.Maximum intensity projection (MIP),curved planar reconstruction (CPR),and volume rendering technique (VR) were obtained.Anomalous termination of coronary artery in each subject was evaluated by two radiologists (with more than 10 years experience with cardiovascular imaging),and disagreement between diagnosis readers was settled by a consensus reading.Ten of 48 patients also underwent traditional coronary angiography (CAG) simultaneously.Results In each CAF case,DSCT angiography clearly demonstrated the origin,the termination,the size of abnormal vessel and its course in relation to surrounding great vessels.CAF arising from right coronary artery was the most common type,left circumflex was the least one involved among three coronaries,and pulmonary artery was the most common drainage site.Aneurismal fistulous tract,coronary atherosclerosis,myocardial bridging and anomalous origin of coronary artery were also detected in this group.The demonstration of drainage sites in CAG was consistent with DSCT angiography in 9 patients,and judgment on one anomalous connection in CAG was inconsistent with that in DSCT angiography.Conclusions DSCT angiography could provide accurate delineation of anomalous communications,size and numbers of fistulas in patients with CAFs.It suggested that DSCT is a useful tool for the assessment of CAFs and may be considered as the first-choice imaging modality,especially for patients with coronary artery disease.