Purpose: Both coronary artery fistula (CAF) and congenital coronary ostial atresia are rare diagnoses. We present a case of an infant with both a right coronary artery to right ventricle (RCA-RV) fistula and right coronary ostial atresia who presented with a murmur, ST-segment changes on EKG, and elevated troponin. We discuss the exam findings associated with CAFs, the clinical significance, and management options. 

Case Description: A 2-week old 35 week neonate was noted to have a continuous murmur on exam. EKG showed diffuse ST-segment changes (figure 1). Echocardiogram demonstrated an RCA-RV fistula with normal biventricular function (figures 2a-2d). Troponin was elevated to 191 (LLN < 22).
Coronary angiography demonstrated right coronary ostial atresia and retrograde filling of the right coronary distribution via a dilated left circumflex coronary artery, with a RCA-RV fistula (Figure 3).

Discussion: CAFs are an abnormal communication between the coronary artery and a cardiac chamber or great vessel. They are relatively rare, with an estimated prevalence of 0.002%, comprising 0.4% of all cardiac malformations. CAFs are more often congenital than acquired and are typically asymptomatic and found incidentally on echo or coronary angiography. If hemodynamically significant, they can present with heart failure.
CAFs can grow, and the majority of patients over 20 are symptomatic. The typical exam finding would be a continuous low-pitched murmur heard best at the left sternal border due to continuous flow from the coronary artery into the low-pressure RV or PA. Treatment options include transcatheter occlusion versus surgical-based approaches such as endocardial closure and epicardial ligation. Both surgical and catheter-based interventions are overall successful with minimum complication rates in both neonates and older individuals. Right coronary ostial atresia is exceedingly rare and typically congenital. Due to the extensive network of collateral vessels, patients typically do not experience ischemia and intervention is rarely required 

Conclusion: This neonate had initial troponin elevation and EKG ST-segment changes. Given the finding of RCA-RV fistula in addition to RCA ostial atresia with right coronary fed from the left coronary, presentation was concerning for coronary steal phenomenon. Due to his size, this patient was not a good candidate for catheter based intervention. Given the lack of symptoms and resolution of initial abnormal findings, the decision was made to discharge with close follow-up. Based on the current literature, CAFs are typically incidental findings that rarely require intervention, but it is uncertain how right coronary ostial atresia impacts that prognosis. With concomitant finding of right coronary ostial atresia, this patient’s CAF may become clinically significant over time and require intervention