We present the case of a 49-year-old female of Caucasian European descent with chest tightness, fatigue, and palpitations, ultimately diagnosed with primary intracardiac angiosarcoma. Initial echocardiography revealed a significant mass within the right atrium, infiltrating the free wall. Surgical intervention included tumor excision and partial resection of the superior vena cava. Histopathological examination confirmed a high-grade angiosarcoma. Postoperative imaging identified a recurrent mass in the right atrium, suggestive of thrombus, alongside Takotsubo cardiomyopathy. Considering the elevated surgical risks and the presence of cardiomyopathy, management included anticoagulation therapy with Warfarin and adjuvant chemotherapy with Paclitaxel. Follow-up cardiac magnetic resonance imaging demonstrated a recurrent angiosarcoma with superimposed thrombus. This case presents the complex diagnostic and therapeutic landscape of angiosarcoma, highlighting the critical importance of early surgical intervention, advanced imaging techniques, and vigilant postoperative monitoring.

Diagnosing intracardiac masses poses a complex, multimodal challenge. We present the case of a 72-year-old woman with a history of rheumatic fever leading to mitral stenosis and a previous mitral valve commissurotomy who reported fatigue, weakness, and palpitations over the past three months. Echocardiography revealed a tumor (53 × 40 mm) in the enlarged left atrium, attached by a wide base to the left atrium wall, exhibiting variable densities. Computerized tomography identified a heterodense mass (53 × 46 × 37 mm) with similar attachments. Angiography showed two branches from the circumflex artery intricately associated with the mass. Despite unsuccessful embolization of the mass’ blood supply, surgical intervention including mitral valve replacement, tricuspid valve annuloplasty, and tumor removal was pursued. Pathohistological analysis confirmed the mass as a thrombus. During the postoperative follow-up, the patient presented with no complaints. Follow-up echocardiography indicated the normal function of the mechanical mitral valve prosthesis and the absence of intracardiac masses. While it remains unknown whether this neovascularization is specific to patients with severe mitral valve disease, this case highlights the diagnostic challenges of differentiating between thrombi and tumors in the context of mitral valve disease. It illustrates the critical role of multimodal imaging in elucidating the anatomical and functional relationships within the heart, thereby guiding accurate diagnosis and effective treatment.