Case Presentation: We describe a 57 year-old man with no significant medical history, who was in his usual state of health until one week prior to presentation when he developed flu-like symptoms, cough, exertional dyspnea and orthopnea. He had a mild sore throat but denied fevers, chills, sputum production or pleuritic chest pain. The patient noted improvement in symptoms on sitting forward. He had a 19-pack year smoking history and he used marijuana recreationally. Family history was significant for myocardial infarction in his brother and breast cancer in his twin sisters and mother. On physical examination, the patient was afebrile with blood pressure 105/70 mmHg and heart rate of 75 bpm. Jugular venous distention and bilateral rales were appreciated. Heart sounds were normal without evidence of murmurs, rubs or gallops. Mild pedal edema was noted but otherwise the physical examination was unremarkable. Electrocardiogram showed sinus tachycardia with occasional PACs, low voltage complexes and a borderline prolonged QTc. Chest x-ray revealed cardiomegaly with mild pulmonary vascular congestion. Three sets of troponin were negative and pro-BNP was 270. Echocardiography showed a circumferential, large pericardial effusion (over 0.5 L) with changes in mitral inflow with respiration consistent with early cardiac tamponade. Pericardial window drained 700 ml of pericardial fluid. ANA, thyroid function tests and ESR were negative. CRP was mildly elevated at 3. Pericardial fluid cytology resulted positive for metastatic adenocarcinoma, weakly positive for TTF-1 suggesting primary neoplasm in the lung. CT scan of the lung was significant for a 13mm lingular (parenchymal) mass, moderate to large right-sided pleural effusion. Thoracocentesis drained 1350ml of fluid, which resulted negative for cytology. PET scan later confirmed primary cancer in the lung. Given stage 4 disease, the patient proceeded with palliative chemotherapy.

Discussion: Cardiac tamponade secondary to malignant pericardial effusion is an oncologic emergency. The incidence of hemorrhagic pericardial effusion with associated cardiac tamponade as a de novo sign of malignancy has been reported as 2%. Cardiac tamponade impairs right ventricular filling, which causes ventricular diastolic collapse and decreased cardiac output, ultimately resulting in death if not treated emergently. Cardiac tamponade may rarely be the initial presentation of adenocarcinoma of the lung.

Conclusions: Cardiac tamponade may be a rare, late presentation of underlying malignancy. It requires emergent management. Our case shows that in some scenarios, echocardiography may demonstrate impending early cardiac tamponade before it becomes clinically evident. A good history and careful physical exam should lead to appropriate investigation and diagnosis. Our case emphasizes an oncologic emergency as a unique initial presentation of malignancy.