Cardiac Tamponade: A Rare Initial Presentation of Thymoma

Abstract

Thymomas represent the predominant type of neoplasm of the anterior mediastinum, constituting approximately a quarter of all tumours found within the mediastinal region. They can present in various ways, including as asymptomatic incidental findings, paraneoplastic syndromes, or symptoms due to the tumour’s spread within the thorax. In advanced cases, pericardial and pleural effusions may develop. Nevertheless, it is extremely rare for a thymoma to initially manifest as a spontaneous bleeding into the pericardial space, resulting in cardiac tamponade. This report illustrates a case of an elderly woman who presented with shortness of breath, reduced effort tolerance, cough, appetite loss, and weight loss. Examination revealed tachycardia, hypotension, distended jugular veins, and muffled heart sounds. Investigations showed anaemia, transaminitis, elevated inflammatory markers, and cardiomegaly with pleural effusions. Echocardiography confirmed cardiac tamponade, and pericardiocentesis drained 1000 ml of haemorrhagic pericardial fluid. CT imaging revealed a large anterior mediastinal mass compressing major vessels. Histopathology confirmed WHO type B2 thymoma. Due to unresectability of the tumour, the patient received palliative chemotherapy but showed disease progression. This case highlights cardiac tamponade as a rare initial presentation of thymoma and emphasises the importance of considering mediastinal malignancy in unexplained pericardial effusions.