Cardiac Myeloid Sarcoma Arising From a Mediastinal Mass Encasing the Aorta: Diagnostic Pitfalls and Challenges

Myeloid sarcoma is a rare extramedullary tumor most commonly associated with acute myeloid leukemia. Cardiac involvement is rare and can pose a diagnostic challenge.

A 40-year-old male with a history of allogenic bone marrow transplant for acute myeloid leukemia presented with angina. Computed tomography angiography raised concern for acute aortic syndrome. Multimodality imaging demonstrated an infiltrative mass encasing the ascending aorta with atrial extension. Conventional biopsy approaches were unsafe due to the lack of a suitable percutaneous window and hemodynamic risks. Intracardiac echocardiography (ICE) guided biopsy-enabled safe tissue sampling confirming myeloid sarcoma. The patient received chemotherapy followed by repeat transplant, achieving remission.

This case highlights a diagnostic pitfall in which an infiltrative malignancy mimicked acute aortic syndrome and highlights the role of ICE-guided biopsy as a safe, alternative diagnostic strategy when standard routes are unsafe.

Multimodality imaging and ICE-guided biopsy are effective and safe diagnostic strategies for complex intracardiac/mediastinal masses.