Abstract
BACKGROUND: Myxomas are the most common primary cardiac tumour, typically presenting as a pedunculated mass growing in the left atrium. Clinical presentation may range from dyspnoea, palpitations, and heart failure to sudden cardiac death, depending on location, size, and mobility. In this report, we describe the case of a giant right atrial myxoma with transmural breakthrough and epicardial growth as well as its successful surgical resection. CASE SUMMARY: A 65 year-old male patient presented with progressive coronary artery disease following prior coronary artery bypass grafting. Cardiac magnetic resonance imaging was performed to assess myocardial vitality, incidentally revealing a round mediastinal tumour of over 6 cm in diameter with compression of the right atrium and the superior and inferior vena cava. As he was experiencing dyspnoea and pectanginous complaints, the patient opted for surgical removal. The epicardial mass was successfully resected under cardiopulmonary bypass and was histologically classified as a myxoma. DISCUSSION: Transmural breakthrough and epicardial growth of cardiac myxomas are extremely rare. Surgical resection can confirm the unexpected diagnosis and alleviate symptoms of heart failure.