Primary Cardiac Angiosarcoma Presenting as Right Atrial Pseudoaneurysm.

Primary cardiac tumors are extremely rare and mostly benign. Cardiac angiosarcoma is the most common malignant cardiac tumor, known for its late presentation and poor prognosis. This report describes the case of a male patient who presented to the emergency department with chest pain and shortness of breath shortly after a viral infection. Chest CT imaging showed a mycotic right atrial pseudoaneurysm with pericarditis and hemopericardium, without gross or pathologic evidence of malignancy after surgery. However, 2 months after discharge, the patient returned with proven metastatic cardiac angiosarcoma. This case highlights the atypical presentation of this rare disease and difficulties in initial early diagnosis. Keywords: CT, Cardiac, Heart, Thorax, Neoplasms-Primary © RSNA, 2025.