Incidental Coronary Sinus Stenosis During Coronary Angiography: A Rare Angiographic Finding

Background The coronary sinus (CS) is a major venous drainage pathway of the heart but is rarely the site of clinically significant pathology. When obstruction of the CS occurs, it can lead to serious hemodynamic consequences and a high risk of mortality if not promptly identified. Case Presentation We report the case of a 60‐year‐old male with Type 2 diabetes mellitus on chronic hemodialysis, who presented with chest pain and dyspnea. While undergoing diagnostic coronary angiography for suspected ischemia, severe stenosis of the CS was incidentally observed. The patient had elevated left ventricular end‐diastolic pressure (LVEDP) and diffuse coronary artery disease. Management included optimization of volume status through intensified hemodialysis, along with guideline‐directed heart failure therapy. The patient′s symptoms and hemodynamic parameters subsequently improved. Conclusion This case highlights the importance of recognizing rare CS abnormalities during coronary angiography. Although the clinical significance of incidental CS stenosis remains uncertain, awareness of such findings may help guide further evaluation in selected patients.