Abstract
Benign metastasizing leiomyoma (BML) is a rare disorder occurring in women with a history of uterine leiomyomas and having detection of leiomyomas in extrauterine locations. This case report describes a 39-year-old female with a six-month history of fatigue and worsening exertional dyspnea. She had undergone a previous myomectomy due to multiple uterine fibroids. A transthoracic echocardiogram revealed a large mass involving the right atrium and the inferior vena cava. Chest and abdominal computed tomography scans demonstrated the presence of this mass in the right hepatic vein, along with a nodule in the right lobe of the liver and multiple uterine fibroids. She underwent surgery to remove the cardiovascular mass, and histopathological results confirmed the benign nature of the smooth muscle cells. Immunohistochemical staining was positive for actin, progesterone receptor, desmin, and Ki67, consistent with a diagnosis of BML. Subsequently, she underwent hysterectomy and bilateral salpingo-oophorectomy, revealing a benign leiomyoma and endometriosis. This case emphasizes the importance of imaging in accurately diagnosing and preoperatively evaluating cardiac mass. LEARNING OBJECTIVE: Benign metastasizing leiomyoma should be considered in patients presenting with an atypical cardiac mass and a history of uterine leiomyoma, myomectomy, or hysterectomy. Multiple imaging modalities are crucial for diagnosis, preoperative evaluation, and surgical treatment guidance.