Anomalous Right Coronary Artery Managed with Bypass and Proximal Ligation

Abstract Background: An anomalous origin and inter-arterial course of the right coronary artery is a rare anomaly that can lead to sudden ischemic cardiac death if left untreated. We present a case of a patient with an anomalous right coronary artery originating from the left coronary cusp and an inter-arterial course that was managed with coronary artery bypass surgery using a right internal mammary artery conduit. The proximal right coronary artery was ligated to prevent competitive flow. Case Presentation: A 69 year-old-male with a ten-year history of intermittent chest pain and dyspnea with a negative workup underwent a cardiac catheterization, which showed an anomalous right coronary artery (RCA) originating from the left coronary cusp, with an inter-arterial course between the ascending aorta and pulmonary artery, and greater than 70% narrowing of the proximal RCA. The patient underwent coronary artery bypass grafting via a median sternotomy and was cannulated for hypothermic cardiopulmonary bypass. The right internal mammary artery (RIMA) was skeletonized and used as a conduit, with the distal RCA being the target. A silastic band was placed around the proximal RCA, and a 2.0mm coronary flow probe (Transonic, Ithaca, NY, USA) was used to measure flow via the conduit with the proximal RCA occluded and un-occluded. With the proximal RCA occluded, peak flow via the conduit was greater due to the elimination of any competitive flow. The proximal RCA was ligated with a 2 − 0 silk suture and three metal clips. Intra-operatively, there were no signs of ischemia or arrhythmia. The patient was successfully taken off cardiopulmonary bypass. Post-operatively, he did well and was discharged on postoperative day 4. Conclusions: Symptomatic anomalous origin of the right coronary artery with an inter-arterial course can be treated successfully with coronary artery bypass surgery with the internal mammary artery as a conduit. Ligation of the proximal right coronary artery can minimize competitive flow through the bypass graft.