Intravenous Leiomyomatosis: An Uncommon Cause of Pulmonary Embolism

BACKGROUND Intravenous leiomyomatosis (IVL) is a rare benign smooth muscle tumor originating in the uterus or in the uterine vessels. It is characterized by continuous intraluminal growth that may extend through iliac veins and inferior vena cava (IVC) to right chambers of the heart and pulmonary vasculature, leading to life-threatening complications. This case report describes an uncommon cause of non-thrombotic pulmonary embolism in young woman caused by extensive IVL. CASE REPORT A 39-year-old woman was admitted after multiple syncopal episodes. She was initially found to have a bilateral pulmonary embolism and large right atrial mass believed to be a thrombus. After an unsuccessful attempt to remove the thrombus with AngioVac (AngioDynamics, Latham, NY), subsequent sternotomy revealed a large pedunculated mass extending to the infra-hepatic IVC. Further abdominal imaging showed multiple uterine masses, with the largest about 17 cm, infiltrating the parauterine vessels and extending through the right iliac vein and inferior vena cava up to the right atrium. Pathology examination of the atrial mass revealed benign leiomyoma consistent with further pathology findings after hysterectomy. The pulmonary embolism was believed to be caused by tumor tissue, and anticoagulation was abandoned. Pulmonary nodule raised a suspicion of benign pulmonary metastases, but, fortunately, remained stable during follow-up and the patient had a successful recovery. CONCLUSIONS Available information about IVL is scarce. This tumor, although benign and rare, should be included in the differential diagnosis of cardiac tumors and non-thrombotic pulmonary emboli in women with predisposing risk factors, as potential complications are life-threatening.