A 65-year-old female known to have type 2 diabetes mellitus, with no significant past medical history, had presented to another hospital with progressive dyspnea, orthopnea, lower limb edema in the two weeks preceding the reporting of this case. Her echocardiography revealed large pericardial effusion with echocardiographic signs of increased intrapericardial pressure. An emergency pericardiocentesis was performed. One week afterwards, she was admitted to the authors’ hospital because of re-accumulation of her large pericardial effusion, which mandated another pericardiocentesis. A CT of the chest revealed enlarged mediastinal lymph nodes (LNs). Video-assisted thoracic surgery (VATS) was done to obtain a pericardial window and a biopsy from the mediastinal LN, which revealed non-caseating granuloma, highly suggestive of sarcoidosis. A few days after surgery she experienced a neurogenic bladder, acute renal shutdown, and metabolic acidosis, during which she developed stress-induced cardiomyopathy that improved a few days later. The patient’s symptoms improved after receiving corticosteroids.