Giant Aorto–Right Ventricular Fistula With Single Coronary Artery
A 15-year-old boy with symptoms of dyspnea and fatigue since early childhood was referred to our institution for evaluation. Physical examination of the patient showed long, slender extremities and a pectus carinatum deformity of the chest (Figure 1A). His arm span–to-height ratio was 1.03, and his upper segment–to–lower segment ratio was 0.82. He had blood pressure of 126/70 mm Hg, with a heart rate of 96 bpm; a grade 4/6 continuous murmur was present in the right lower parasternal area. A 12-lead ECG showed right bundle-branch block (Figure 2), and chest radiography (posteroanterior view) revealed mild cardiomegaly. Radiography of the thoracolumbar spine of the patient disclosed a mild degree of scoliosis (inset, Figure 1A). Two-dimensional echocardiography (parasternal long-axis view) showed a large fistula (2 cm in diameter) arising from the right aortic sinus (Figure 1B; online-only Data Supplement Movie I). A tilted apical 4-chamber view showed a turbulent jet (velocity 3.5 m/s) at the free wall of the right ventricle (Figure 1C; online-only Data Supplement Movie II). Three-dimensional echocardiography in a tilted apical 5-chamber view showed a broad tunnel arising from the aorta (Figure 1D; online-only Data Supplement Movie III). Computed tomographic cardiac angiography revealed the presence of a single coronary artery that originated from the left aortic sinus and divided into the left anterior descending and circumflex arteries and confirmed the presence of a large fistula that arose from the dilated right aortic sinus, with a tortuous course and termination into the anterosuperior portion of the right ventricle (Figures 1E and 3A and 3B). Cardiac catheterization showed a left-to-right shunt with a pulmonary-to-systemic blood flow ratio (Qp:Qs) of 2:1 and pulmonary artery systolic pressure of 50 mm Hg. Selective hooking of the right aortic sinus and aortic root angiogram confirmed the origin of the fistula from the right coronary sinus (Figure 4). Coronary angiography of the patient revealed a single coronary artery that split into the left anterior descending and circumflex arteries. The ostium of the right coronary artery could not be hooked, and the right side of the heart was supplied entirely from branches arising from the left coronary circulation (Figure 1F). Because the patient had marfanoid habitus with dilated right aortic sinus and a test for fibrillin gene mutation was negative, the diagnosis of a Marfan-like disorder was made.
During surgery, after performance of a median sternotomy and pericardiotomy, a fistula was seen arising from the ascending aorta (Figure 5). After cardiopulmonary bypass was established, the fistula was traced from the right aortic sinus toward the right ventricle. The rudimentary ostium of the right coronary artery was also visualized after aortotomy, adjacent to the origin of the fistula (Figure 6). Dacron patch closure of the aortic side of the fistula was performed, and a small pericardial patch was placed at the right ventricular opening of the fistula. The remaining fistulous track was closed by primary closure. There was a complete disappearance of the murmur after closure, and the postoperative course of the patient was uneventful. The patient is doing well after 6 months of follow-up.
An aorto–right ventricular fistula is a rare congenital extracardiac malformation that links the ascending aorta to the cavity of the right ventricle.1 The probable cause of this anomaly appears to be related to congenital weakness in the wall of the sinus of Valsalva and gradual rupture into the right ventricle. Other reports describe such cases as traumatic in origin; however, there was no history of previous chest trauma in the present case. Associated coronary abnormalities include absent right or left coronary ostia or abnormal origin of coronary arteries.2 This vascular channel functions like a left-to-right shunt at the ventricular level, and complications can be in the form of volume overload of both ventricles, pulmonary vascular disease, and spontaneous rupture or aneurysm formation.3 Two-dimensional echocardiography can readily demonstrate the 2 ends of the fistula. Computed tomographic angiography or cardiac catheterization with angiography remains an important adjunctive tool to confirm the diagnosis and delineate the coronary artery anatomy before closure.4 Differentiation from the ruptured aneurysm of the sinus of Valsalva can be made on the basis of the patient's clinical profile and angiographic findings. Closure of the fistula is usually recommended in view of the future risk of complications. Surgical closure remains the primary option in the management of aorto–right ventricular fistula; however, transcatheter closure has been attempted.4 This case represents a rare form of association of a huge aorto–right ventricular fistula with a single coronary artery in a patient with Marfan-like disorder, which has not been described previously.
The online-only Data Supplement is available with this article at http://circ.ahajournals.org/lookup/suppl/doi:10.1161/CIRCULATIONAHA.111.045039/-/DC1.
- © 2012 American Heart Association, Inc.