Role of transesophageal echocardiography in decision-making of coronary artery obstruction in surgical aortic valve replacement

Background: Acute coronary artery obstruction is a rare but lethal complication of surgical aortic valve replacement (SAVR), which may be caused by embolization of resected native tissue such as calcium plaque, thrombus or perivalvular aortic tissue like fatembolus. Coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) are the main treatment modalities. PCI is less invasive, but it is difficult to determine its feasibility intraoperatively. Case presentation We report an 86-year-old woman who had asymptomatic severe aortic stenosis. She had scleroderma with an intractable left leg ulcer and bilateral leg varices. Considering the possibility of the spread of infection from the leg wound, SAVR was performed via right anterior thoracotomy to avoid complications such as mediastinitis. Coronary artery occlusion was suspected after weaning of cardiopulmonary bypass in the operation room due to asynergywith ST elevation and new severe mitral regurgitation. Transoesophageal echocardiography (TEE) helped diagnose coronary obstruction by embolus based on the degree of stenosis and the movement of the stenosis site. Percutaneous catheter intervention was performed successfully to restore coronary perfusion. Conclusion: Repeated and continuous TEE enabled the diagnosis of coronary artery stenosis caused by embolus and helped ascertain the feasibility of percutaneous catheter intervention. This is especially invaluable in cases where obtaining a saphenous graft for CABG is difficult or where CABG would have required conversion from minimally invasive surgery (anterolateralapproach) to median sternotomy. By communication with anesthesiologists who performed repeated and continuous TEE during an operation, we were able to select a less invasive surgery for the patient.