Imaging features of right atrial lipoma on multimodality imaging

Rationale: Cardiac lipoma is the second most common benign primary cardiac tumor. It can arise in any cardiac chamber and often presents with no or only nonspecific symptoms. Its variable morphology poses a diagnostic challenge. Patient concerns: A 53-year-old asymptomatic female patient reported no history of palpitations, chest tightness, or other discomfort, and denied lower extremity edema or limitation of physical activity. During a routine health checkup, transthoracic echocardiography (TTE) revealed a mass at the junction of the superior vena cava and the right atrium. She then presented to our hospital for further evaluation. Diagnoses: Further evaluation with transesophageal echocardiography (TEE) revealed a right atrial mass with hypoechoic to isoechoic characteristics, measuring approximately 2.86 cm × 1.62 cm. Computed tomography demonstrated a well-circumscribed nodular lesion with fat attenuation within the right atrium. Positron emission tomography–computed tomography revealed minimal glucose uptake in the mass, with a maximum standardized uptake value of 1.3. Cardiac magnetic resonance imaging showed low signal intensity on T2-weighted fat-suppressed images. The diagnosis of a right atrial lipoma was ultimately established following surgical excision and histopathological confirmation. Interventions: The patient underwent cardiac tumor resection, and the mass was completely removed. Postoperative pathology confirmed it as a cardiac lipoma. The patient remained hemodynamically stable after surgery, and no recurrence has been observed during follow-up to date. Outcomes and lessons: This case highlights the complementary diagnostic value of TEE in conjunction with TTE and demonstrates that a comprehensive multimodality imaging approach improves diagnostic accuracy for cardiac lipomas and facilitates differentiation from benign myxomas and malignant liposarcomas. Take-home message: Right atrial lipoma is a benign tumor with variable morphological features. An integrated multimodality imaging approach is crucial for achieving a reliable diagnosis and guiding appropriate clinical management.