Surgical management of a dilated right coronary artery–coronary sinus fistula with ANOCOR: a case report

Abstract Background Coronary artery fistulas are uncommon anomalies that may remain silent for years but can ultimately lead to myocardial ischaemia or heart failure through coronary steal and dilatation of the receiving chamber or vessel. Management ranges from conservative follow-up to transcatheter closure or surgical repair, depending on fistula size and haemodynamic impact. In complex right coronary artery fistulas draining into the coronary sinus with associated anomalies, surgical closure combined with myocardial revascularization may offer the most reliable result. Case summary A 70-year-old woman had an incidentally discovered right coronary artery–coronary sinus fistula with an associated aneurysm and remained asymptomatic before developing exertional angina. Coronary CT angiography showed progression of coronary sinus dilatation with multiple fistulous connections and an anomalous circumflex artery originating from the right coronary artery with a retro-aortic course, while left ventricular ejection fraction was preserved. Surgical correction under cardiopulmonary bypass consisted of closure of the main fistula and sequential coronary artery bypass grafting, with a saphenous vein graft anastomosed end-to-side to the posterior descending artery and side-to-side to a right marginal branch. Postoperative recovery was uneventful with discharge on day 6, and at 6-month follow-up the patient was asymptomatic without recurrence of angina. Discussion Right coronary artery–coronary sinus fistulas may remain clinically silent yet eventually present with exertional angina through a coronary steal mechanism in the absence of atherosclerotic disease. Multimodality cardiac imaging, particularly coronary CT angiography, is crucial to delineate complex anatomy and identify associated coronary anomalies that guide management decisions. Surgical correction combining fistula closure and revascularization of the right coronary territory is an effective option in selected patients with large, anatomically complex fistulas.