Unusual Location of a Posterior Lipoma Originating From the Left Atrial Roof: Case Report and Review of the Literature

Lipomas are the most common type of soft tissue tumors. They mainly are located in subcutaneous tissue in the body, including the heart. The cardiac location of lipomas is rare, mostly asymptomatic, and can cause life-threatening complications by rapid growth. The clinical symptoms, when present, occur in evolution with the growth in size, depending upon the location and degree of invasion in the endocardium. We present the case of a 63-year-old male patient with a large intrapericardial lipoma with an unusual location, originating from the left atrial roof. The initial symptoms of the patient were shortness of breath, dizziness, and mild dyspnea. Transthoracic echocardiography (TTE) was the first line diagnosis method, followed by computed tomography (CT); both showed a large posterior intrapericardial mass. Resection of a 12/8/5 cm lipomatous tumor mass was performed via median sternotomy, under cardiopulmonary bypass (CPB) on the beating heart. Histopathologic examination revealed the presence of diffuse proliferation of large- and medium-sized mature adipocytes consistent with the diagnosis of pericardial lipoma. The patient was discharged at home on the seventh postoperative day, with a marked improvement of his clinical state and effort tolerance. He did not present evidence of recurrence at his 1-year follow up.