Epicardial mesothelial cyst originating from the roof of the left atrium: a case report

Background: Epicardial mesothelial cysts are cysts that are attached to the epicardium within the pericardial cavity. Reports on epicardial mesothelial cysts are rare, and limited studies have investigated their surgical management. Here, we report the rare case of an epicardial cyst originating from the roof of the left atrium. Case summary: A 73-year-old man with dyspnoea on exertion and lower limb oedema was diagnosed with a giant cyst (diameter, 7 cm × 4.5 cm) in the pericardial cavity using computed tomography. Off-pump surgery was performed with successful resection of the cyst with a pedicle connected to the roof of the left atrium. Histological examination confirmed the mesothelial origin of the tumour cells. Conclusion: Cysts rarely develop within the pericardial cavity, especially an epicardial cyst. The few studies exploring this disease have suggested that patients with this condition may be asymptomatic or have mild breathlessness or cardiac tamponade, which might be occasionally or incidentally diagnosed. Sufficient preoperative evaluation, particularly involving the coronary artery, is essential, and a rational way of surgery should be planned considering all factors.