A 21-year-old man presented initially with impending cardiac tamponade secondary to an angioimmunoblastic T-cell lymphoma (AITL). Following unsuccessful pericardiocentesis and subxiphoid pericardiostomy, the patient's deteriorating hemodynamics prompted an urgent sternotomy. Histopathological diagnosis confirmed AITL. While chemotherapy remains the most effective treatment of AITL, life-threatening complications of the tumor necessitates surgical intervention.