Worsening cardiac tamponade after pericardiocentesis in a patient with anterior mediastinum mass: a case report.

Background: Mediastinal mass is an entity with variable pathology and clinical spectrum. Anterior mediastinal mass can result in severe symptoms due to involvement of surrounding vital structures such as the great vessels, trachea-bronchial tree, and heart. We highlight a case of cardiac tamponade in a patient with an anterior mediastinal mass that was paradoxically worsened after decompressive pericardiocentesis. Case summary: A 21-year-old male presented to the emergency department (ED) with breathlessness and hypotension. Bedside focused cardiac ultrasound revealed cardiac tamponade which was made worse with an anterior mediastinal mass compressing the right heart chambers. The patient was intubated for respiratory failure, following which an ultrasound-guided pericardiocentesis was performed. Unexpectedly, his hemodynamic status worsened after aspiration of 1000 mL of pericardial fluid. A repeat focused cardiac ultrasound showed reduced pericardial effusion, but worsening of right heart chambers compression by the mediastinal mass. Re-expansion of the pericardium space with 600 mL of normal saline improved the patient's vital signs, and reduced the right heart compression. Computed tomography was deferred due to the patient's hemodynamic instability. Despite resuscitation with fluids and initiation of vasopressor, the patient's condition deteriorated. He succumbed to his illness due to obstructive shock causing multi-organ failure. The autopsy showed a large anterior mediastinal mass, and histopathological examination confirmed the diagnosis of lymphoma. Discussion: This case demonstrated the therapeutic challenges of managing a shock patient with anterior mediastinal mass, and massive pericardial effusion causing cardiac tamponade.