Sinoatrial Nodal Artery-to-Right Atrium Coronary Cameral Fistula in an Infant: Multimodality Imaging and Hemodynamic Interpretation

Coronary cameral fistula is a rare congenital anomaly characterized by an abnormal communication between a coronary artery and a cardiac chamber. We report a 7-month-old infant with a restrictive sinoatrial nodal artery-to-right atrium fistula identified on transthoracic echocardiography and further defined by cardiac computed tomography. Additional lesions included an ostium secundum atrial septal defect and a small patent ductus arteriosus, together contributing to the overall left-to-right shunt burden. Baseline electrocardiography showed sinus rhythm without sinus node dysfunction or clinically significant atrial arrhythmia. The case highlights the value of multimodality imaging in establishing the anatomical diagnosis, interpreting hemodynamic significance in the presence of coexisting shunts, and supporting conservative follow-up in a rare coronary anomaly.