Mysterious Floating Structure in the Left Atrium After Coronary Artery Bypass Grafting

A 60-year-old male patient was referred to our hospital for coronary artery bypass graft surgery due to prior subacute myocardial infarction and subsequently angiographically diagnosed 3-vessel coronary artery disease. Preoperative transoesophageal echocardiography (TEE) revealed wall motion abnormalities, but was otherwise unremarkable. During stepwise reduction of the extracorporal circulatory assistance after uneventful course of the surgical procedure, the routinely conducted TEE revealed a well-defined homogeneous floating structure in the left atrium (Figure 1A,B). Diagnosis of a perioperative thrombus formation in the left atrium was proposed. Hence, the left atrium was incised to explore the structure leading to the diagnosis of an inverted left atrial appendage. Inversion of the left atrial appendage following cardiac surgery is a rare but important complication that can be transient showing spontaneous eversion. It can, however, result in serious complications such as necrosis with potential rupture of the left atrial wall. Therefore decision was taken towards surgical reduction of the inverted left atrial appendage. In the case of peri- or postoperative appearance of a new clearly delineated floating structure in the left atrium, an inverted left atrial appendage has to be taken into account.