Coronary artery fistula with or without aneurysm: A large comparative study

Background: The knowledge of coronary artery fistula (CAF) with coronary aneurysm mostly comes from case reports and is very limited. However, the management of CAF with and without aneurysm is different, more understanding of its clinical and imaging features is necessary. This is the first research focus on it through a large comparative study.Purpose: To investigate the differences in imaging and clinical features of CAF with and without aneurysms.Methods: We reviewed 96,037 consecutive patients undergoing coronary computed tomography angiogram (CCTA) between 2016 and 2020 and total of 429 CAF adult patients were enrolled. Those patients were divided into the CAF with aneurysm group (321 cases, 74.83%) and CAF without aneurysm group (108 cases, 25.17%) according to whether complicated with coronary aneurysm. Clinical baseline data, electrocardiographic (ECG) characteristics, the presence or absence of coronary atherosclerosis, complication symptoms and fistulous origin, entry site, number and diameter were analyzed. Chi-square test, T-test, Mann-Whitney U tests, and logistic regression analysis were performed.Results: Most of the clinical baseline data did not differ significantly between the two groups (P > 0.05). However, heart murmur, coronary atherosclerosis, infective endocarditis (IE), fistulous diameter and fistulous entry site were significantly different (P<0.05). Further multivariate logistic regression analysis showed that large fistulous diameter and coronary-cardiac chamber arterial fistulas was dependent risk factors for CAF complicated with aneurysm.Conclusion: CAF patients with aneurysm were more prone to develop heart murmur than those patients without aneurysm. Different from other sites of aneurysms, coronary atherosclerosis is more common in CAF without aneurysm. Larger fistulous diameter and coronary-cardiac chamber arterial fistula are dependent risk factors for CAF with aneurysms.