Sinus Node and Right Coronary Artery Aneurysms With Atrial Fistula: A Case Report and Literature Review

Background: Sinus node artery aneurysms are exceptionally rare, especially when combined with a right coronary artery aneurysm and a fistulous tract draining into the right atrium. Only two adult cases with this triad have been reported. We present the youngest known adult with this anomaly, aiming to emphasize the value of early imaging-based diagnosis and individualized surgical management. Case presentation: A 23-year-old male presented with a one-year history of exertional dyspnea. Physical examination and laboratory tests were normal. Transthoracic echocardiography suggested a coronary fistula with abnormal continuous flow into the right atrium. Contrast-enhanced computed tomography revealed a 13 mm sinus node artery aneurysm arising from a proximally aneurysmal right coronary artery (12 mm) and draining via a 9 mm fistula into the right atrium. The right atrium was markedly dilated. Surgical correction was performed under cardiopulmonary bypass. The intra-atrial fistulous orifice was closed using pledgeted sutures and the extracardiac tract was ligated. The sinus node artery was preserved, and no reconstruction was performed on the right coronary artery. The patient recovered without complications and was discharged on postoperative day seven with preserved sinus rhythm. Conclusion: This case highlights an extremely rare coronary artery anomaly in a young adult. Large fistulas, even when associated with moderate aneurysms, may cause significant volume overload and warrant early intervention. Our case reinforces the importance of multimodal imaging and timely surgery to prevent progression and preserve cardiac function.