Imaging Findings of Coronary Artery Fistula in Children: A Pictorial Review

Abstract

Coronary artery fistula, defined as an abnormal communication between the coronary arteries and a cardiac chamber (most commonly) or a thoracic great vessel, may result in hemodynamically significant problems due to vascular shunting in children. Echocardiography, cardiac catheterization, cardiac MRI, and cardiac CT may be used to evaluate coronary artery fistula in children. Recently, CT has played a pivotal role for the accurate diagnosis of coronary artery fistula in children. Surgical or interventional treatment is performed for hemodynamically significant coronary artery fistulas. In this pictorial review, the detailed imaging findings of coronary artery fistula in children are described.

Keywords: Cardiac CT; Cardiac catheterization; Children; Coronary artery anomalies; Echocardiography.

Fig. 1. Coronary cameral fistula between the right coronary artery and the RV.

A. Initial frontal volume-rendered CT image showing the diffusely dilated right coronary artery in a 5-month-old boy. B, C. Initial inferior volume-rendered CT images with a full slab (B) and with a thinner slab (C) demonstrating the single drainage site of the fistula into the inferomedial basal portion of the RV. Two narrowings (arrows) are noted at the drainage site. D, E. Follow-up frontal (D) and inferior (E) volume-rendered CT images performed 8 years later showing increased dilatation of the right coronary artery and the development of aneurysmal change (asterisk) at the drainage site. The two narrowings (arrows) showed interval increase in diameter due to increased left-to-right shunt through the fistula. LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 2. Coronary cameral fistula between the LAD artery and the RV in a 5-year-old boy.

A. Oblique lateral volume-rendered CT image showing the diffusely dilated LAD artery and a D branch in a 5-year-old boy. B, C. Inferior volume-rendered CT images with a full slab (B) and with a thinner slab (C) demonstrating the single drainage site (arrows) of the fistula into the inferomedial basal portion of the RV. D = diagonal, LA = left atrium, LAD = left anterior descending, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 3. Coronary cameral fistula between the left circumflex artery and the RV in a 1-month-old boy.

A. Oblique lateral volume-rendered CT image with frontal cut showing the diffusely dilated left circumflex artery (arrows) anomalously connecting to the inferomedial basal portion of the RV in a 1-month-old boy. B. Oblique lateral catheter ascending aortographic image showing the diffusely dilated left circumflex artery (asterisks) draining into the inferomedial basal portion of the RV (long arrow). A normal right coronary artery (short arrows) was noted. AA = ascending aorta, MPA = main pulmonary artery, RV = right ventricle

Fig. 4. Coronary cameral fistula between the conal branch of the right coronary artery and the RV.

A. Initial superior volume-rendered CT image showing the dilated conal branch (short arrows) draining into the outflow tract of the RV (long arrow) in a 9-month-old girl. B. Color-coded volume-rendered CT image demonstrating the coronary cameral fistula and the AA in red, and the normal right and left coronary arteries in blue. C, D. Frontal selective catheter right coronary arteriographic images performed 5 years later confirming the coronary cameral fistula (C), and an occluding device (arrow) was placed in the distal part of the fistula (D). AA = ascending aorta, LV = left ventricle, MPA = main pulmonary artery, RA = right atrium, RV = right ventricle

Fig. 5. Coronary cameral fistula between the right coronary artery and the LV in an 8-month-old girl.

A. Superior volume-rendered CT image showing the diffusely dilated right coronary artery (asterisks) in an 8-month-old girl. B. Inferior volume-rendered CT image revealing the abnormal connection (arrow) between the right coronary artery and the LV. C. Curved planar reformatted CT image demonstrating the entire course (arrows) of the fistula. AA = ascending aorta, CS = coronary sinus, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 6. Coronary cameral fistula between the right coronary artery and the RA in an 11-day-old boy.

A. Oblique coronal CT image showing the severely dilated origin and proximal portion of the right coronary artery (asterisk) in an 11-day-old boy. The left coronary artery (arrows) was normal in size. B. Oblique axial CT image revealing the fistulous connection (arrow) between the dilated proximal right coronary artery (asterisks) and the RA. AA = ascending aorta, DA = descending aorta, LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 7. Coronary artery-to-coronary sinus fistula.

A–C. Initial oblique coronal CT images showing the severely dilated left circumflex artery (asterisks) anomalously draining into the dilated CS in a 3-day-old girl. D. Frontal selective catheter left circumflex arteriographic image performed on the same day confirming the diagnosis of coronary artery-to-coronary sinus fistula. E. Follow-up oblique coronal CT image performed one month after surgical ligation of the fistula showing stumps (arrows) of the left circumflex artery and the CS. AA = ascending aorta, CS = coronary sinus, LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 8. Coronary artery-to-middle cardiac vein fistula.

A. Axial coronary MR angiographic image showing a fusiform enlarged vascular space (asterisks) at the basal portion of the RV in a 2-year-old boy. B, C. Cardiac volume-rendered CT images performed 3 years later showing the mildly dilated left anterior descending artery (arrows). However, the enlarged vascular space (asterisks) detected on MRI was barely seen. D, E. Frontal selective catheter left coronary arteriographic images performed 4 years later demonstrating the abnormal connection (arrow) between the left anterior descending artery and the middle cardiac vein, delayed opacification of the enlarged vascular space (asterisks), and the cardiac veins. CS = coronary sinus, LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle

Fig. 9. Ventriculo-coronary arterial connections in a 1-day-old girl with pulmonary atresia, an intact ventricular septum, and hypoplastic tricuspid valve.

A, B. Oblique superior volume-rendered cardiac CT images obtained at end-systolic (A) and end-diastolic (B) phases showing the severely dilated left anterior descending artery and the mildly dilated right coronary artery connected to the hypoplastic RV at multiple sites in a 1-day-old girl. Notably, diastolic flow to the left anterior descending artery was significantly compromised (arrows), which may contribute to myocardial ischemia. C. Oblique axial CT image demonstrating pulmonary atresia (arrow) with confluent central branch pulmonary arteries. D. Four-chamber CT image showing the hypoplastic tricuspid valve (arrows), the hypoplastic RV, and the intact ventricular septum. AA = ascending aorta, DA = descending aorta, LA = left atrium, LPA = left pulmonary artery, LV = left ventricle, RA = right atrium, RPA = right pulmonary artery, RV = right ventricle

Fig. 10. Ventriculo-coronary arterial connections in pulmonary atresia and an intact ventricular septum.

A. Initial frontal catheter right ventriculographic image showing multiple abnormal connections between the hypoplastic RV and the dilated coronary arteries in a 5-year-old boy. B. Follow-up frontal selective catheter left coronary arteriographic image obtained after coil embolization (long arrow) of the fistulous connection between the hypoplastic RV and the right coronary artery 2 years later showing residual connections (short arrows) between the hypoplastic RV and the dilated left anterior descending artery. C, D. Frontal (C) and inferior (D) volume-rendered cardiac CT images performed at the age of 24 years after extracardiac conduit Fontan operation demonstrating residual connections (arrows in C) between the hypoplastic RV and the dilated left anterior descending artery. The right coronary artery remained dilated after coil embolization (long arrow in D), suggesting residual shunt flow between the RV and the right coronary artery. A normal posterolateral branch (short arrows in D) of the right coronary artery was noted. AA = ascending aorta, LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle