Case Report: A large right atrial hemangioma: multimodal imaging and postoperative follow-up.

Primary cardiac tumors are extremely rare, and hemangiomas represent only a small subset, with right atrial involvement being particularly uncommon, posing diagnostic challenges due to non-specific symptoms and overlapping imaging features. We present a 55-year-old male with an incidentally discovered right atrial mass initially suspected to be a myxoma. Multimodal imaging with transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) was performed: TTE identified a large mobile mass causing partial tricuspid obstruction, while CMR with quantitative diffusion-weighted imaging/apparent diffusion coefficient (DWI/ADC) provided detailed tissue characterization and anatomical mapping, revealing typical features of a hemangioma. Surgical resection was performed via median sternotomy under cardiopulmonary bypass. The mass, arising from the right atrial posterior wall and interatrial septum, was completely excised, and the atrial defect was repaired with a pericardial patch. Histopathology and immunohistochemistry confirmed a benign capillary hemangioma. Postoperative echocardiography demonstrated reduced right atrial diameter, resolution of obstruction, and mild stable tricuspid regurgitation, with no major complications. Combined TTE and CMR multimodal imaging is crucial for accurate preoperative diagnosis and surgical planning of right atrial hemangiomas. Complete surgical resection achieves favorable outcomes, and long-term multimodal imaging follow-up is recommended to exclude recurrence.