Giant Left Circumflex Coronary Artery Aneurysm With Arteriovenous Fistula to the Coronary Sinus
An 80-year-old woman with a history of breast cancer status post radiation therapy, paroxysmal atrial fibrillation, and congestive heart failure was referred to our institution for evaluation of a giant left circumflex (LCx) coronary artery aneurysm with fistulous communication to the coronary sinus. The patient initially presented with shortness of breath and non-ST elevation myocardial infarction associated with anterolateral T-wave inversion on ECG (Figure 1). Chest radiography showed a dense structure with a circular silhouette at the projection of the superior right mediastinum at the location of the right atrium in the posterior-anterior view and in the posterior mediastinum in the lateral view (Figure 2). She underwent cardiac catheterization, which showed no significant obstructive epicardial coronary artery disease. However, the angiogram revealed a large LCx coronary artery aneurysm with fistulous communication to the coronary sinus (Figure 3A and 3B; online-only Data Supplement Movies I and II). To better define the anatomic relationship of this aneurysm, a contrast-enhanced 64-slice multidetector computed tomography (MDCT) was performed. The location of the aneurysm was noted to be posterior to the left ventricle in juxtaposition with the left atrium, and its size measured 6.0 cm × 5.6 cm × 4.8 cm (Figure 4A through 4E; online-only Data Supplement Movie III). An intraoperative transesophageal echocardiogram was performed and confirmed the presence of the aneurysm and LCx fistula to the coronary sinus (Figure 5A and 5B; online-only Data Supplement Movies IV and V). The patient underwent successful surgical resection of the LCx aneurysm with ligation of the LCx just proximal to the aneurysm (Figure 6A and 6B). The outflow of the aneurysm was ligated at the coronary sinus. Postoperative intraoperative transesophageal echocardiogram demonstrated residual ectasia of the LCx coronary artery proximal to the site of ligation and no evidence of coronary aneurysm or fistulous communication with the coronary sinus (online-only Data Supplement Movie VI). Surgical pathology revealed atheromatous changes in the vessel wall of the aneurysm with extensive fibrosis and calcification (Figure 6C). Her postoperative course was uneventful, and she has remained well at 4-month follow-up.
Coronary artery fistulous communication is rare, with a reported incidence of 0.1 to 0.2%. There have only been a few reported cases of aneurysmal circumflex coronary arteries with fistulous connection to the coronary sinus.1,2 Our case represents the largest reported LCx coronary aneurysm reported in association with fistulous connection between the left circumflex coronary artery and the coronary sinus. Symptoms on presentation may include shortness of breath, fatigue, angina, and infective endocarditis. There remains no standard of management or clinical algorithm for this rare pathology, though diagnosis and treatment may stand to benefit from improved cardiac imaging modalities. MDCT may provide superior visualization of aneurysmal coronary fistulas and its anatomic relationship to the adjacent structures and could help guide surgical or endovascular treatment strategies.2–4
We thank the Massachusetts General Hospital Echocardiography and Pathology laboratories for providing great clinical care.
Dr. Truong has received support from National Institutes of Health grant T32HL076136. The other authors report no conflicts.
The online-only Data Supplement is available with this article at http://circ.ahajournals.org/cgi/content/full/118/22/2304/DC1.