Successful Surgical Repair of Adult Anomalous Origin of the Left Main Coronary Artery from the Pulmonary Artery Complicated by a Mass in the Left Atrial Appendage: A Case Report.

Abstract

Introduction: An anomalous origin of the left coronary artery (LCA) from the pulmonary artery (PA) (ALCAPA) is a rare congenital abnormality associated with high rates of early infant mortality and sudden death in adults.

Case presentation: A 56-year-old woman with acute left lower extremity arterial occlusion was diagnosed with an adult ALCAPA with a mass in the left atrial appendage. Preoperative echocardiography revealed left ventricular hypokinesis posteroinferior to the lateral wall and moderate mitral valve regurgitation, with a mass in the left atrial appendage. Coronary angiography revealed ALCAPA and dilatation of both coronary arteries. Myocardial scintigraphy revealed infarction of the posteroinferior wall and severe ischemia of the lateral wall of the left ventricle. We occluded the LCA entry from the inside of the PA and performed a left internal thoracic artery-to-left anterior descending artery (LITA-LAD) bypass, mitral annulus plasty, and resection of the mass together with the left atrial appendage. Because of residual myocardial blood flow from the collateral vessels, we cooled the temperature to 28°C to induce cardiac arrest. Postoperative coronary angiography indicated a good LITA-LAD flow and improvement in left ventricular contractility. Myocardial scintigraphy revealed improvement in ischemia. Pathological examination revealed that the mass in the left atrial appendage was a thrombus. The patient's postoperative course was uneventful. She was discharged on postoperative day 16 and was given oral warfarin as anticoagulation therapy. Six months later, the follow-up evaluation was uneventful, and the patient was free of any symptoms of heart failure.

Conclusions: We encountered a very rare case of ALCAPA complicated by a left intra-atrial mass following acute lower extremity artery occlusion. We performed LITA-LAD bypass, mitral annulus plasty, and resection of the mass along with the left atrial appendage. Due to residual myocardial blood flow from the collateral circulation, we cooled the temperature to 28°C in preparation for inducing cardiac arrest. The postoperative course was uneventful.