A 62-year-old man presented with 2 weeks of progressive dyspnea and chest pain. He was previously diagnosed with high-grade invasive urothelial carcinoma (UC) of the bladder and underwent neoadjuvant chemotherapy followed by radical cystectomy 10 months earlier, resulting in pathologic complete remission. Clinical evaluation and echocardiographic imaging was consistent with a diagnosis of cardiac tamponade. Due to a history of malignancy, the patient was referred for a surgical pericardial window, to include biopsy of the pericardium. Pericardial fluid and pericardial biopsy specimens were consistent with metastatic UC. Cardiac tamponade due to metastatic UC is a rare presentation, and, to our knowledge, there have been only 5 cases reported in the English literature. We report a rare case of cardiac tamponade due to isolated pericardial metastases from high grade UC of the bladder and discuss the symptoms, treatment, and prognosis of this pathologic condition. We also present a brief review of previously published literature. Through this discussion, we would like to emphasize the (1) consideration of cardiac metastases in the differential diagnosis for patients with a history of UC presenting with cardiac or pulmonary symptoms and (2) improved diagnostics with pericardial biopsy and pericardiocentesis over pericardiocentesis alone.