12 March 2025
: Case report 
Thymoma-Induced Severe Biventricular Failure without Myasthenia Gravis: Investigating Tachycardia-Induced Cardiomyopathy
Challenging differential diagnosis, Unusual or unexpected effect of treatment, Rare disease, Rare coexistence of disease or pathology
Roscoe Lim AEF 1,2, Stephanie Wiltshire AEF 1, Megan Barnet
E 3,4,5,6, Julia P. Low BE 3,7, Samuel Bolitho E 8, Alisa Kane E 9, Andrew Jabbour E 1, Eugene Kotlyar E 1, Christopher Hayward AE 1,3,10*
DOI: 10.12659/AJCR.945796
Am J Case Rep 2025; 26:e945796
Table 2. Comparing cases of thymoma without clinical MG presenting with heart failure.
| Authors | Patient demographics | Presenting rhythm | Imaging | Pathology and immunohistochemistry | MG-related antibodies |
|---|---|---|---|---|---|
| Tabet, et al []12 | 31-year-old man with 2-week history of worsening exertional dyspnea, ascites, and lower limb edema | Sinus tachycardia | CT: retrosternal irregular mass (69×46 mm) with pericardial effusion and bilateral pleural effusion | Lympho-epithelial thymoma with atypical and aggressive cells. Positive anti-LCA, anti-pan cytokeratin, and anti-CD1a antibodies | Acetylcholine and MusK antibodies negative |
| Priester, et al []13 | 60-year-old man with biventricular cardiac failure | Sinus tachycardia | CT: mediastinal tumor with infiltration to both lungs, vascular structures, and dissemination to chest well | Invasive cortical thymoma, no immunohistochemistry provided | Not provided |
| Presented Case | 33-year-old male with 2-week history of dyspnea, orthopnea, ascites, and lower limb edema | Atrial flutter | CT: anterior mediastinal mass measuring 118×79 mm with right pleural metastasis and trans-diaphragmatic extension | Large cohesive epithelioid cells, forming sheets with significant proportion of infiltrating mature lymphocytes. Positive C3, CD5, CD99, and CD1a | Acetylcholine antibody positive, MusK antibody negative |