BACKGROUND: Intracardiac leiomyomatosis (ICL) is an uncommon condition characterized by the proliferation of intravascular tissue within the veins, leading to the development of tumor emboli. This can pose a significant threat to life when the tumor invades cardiac structures. The diagnostic process for this condition is complex and presents considerable challenges. CASE PRESENTATION: We report a case of a 38-year-old female patient whose pulmonary artery computed tomography (CT) revealed low density structure in the branches of the pulmonary artery. Echocardiography revealed a mobile tumor within the right heart chambers and pulmonary trunks as well as characteristic thickening of the ventricular septum consistent with hypertrophic cardiomyopathy (HCM). Magnetic resonance imaging (MRI) revealed a mass in the right anterior uterine wall, extending to the inferior vena cava (IVC) and right iliac vein. Post-surgery histopathological analysis confirmed a diagnosis of intravenous leiomyomatosis (IVL). CONCLUSIONS: When IVL affects the heart, echocardiography is the best diagnostic tool for detecting the disease. CT and MRI are essential in identifying the location and extent of the tumor, as well as in evaluating prognosis.