Abstract 18453: Giant Right Atrial Lipoma Inducing Atrial Flutter and Tachycardia-Mediated Cardiomyopathy: The Value of Multimodality Cardiac Imaging

Abstract

Case Presentation: A 60-year-old male who presented with progressive dyspnea on exertion and atrial flutter with rapid ventricular response. His TTE showed a large (5.1 x 3.9 cm) right atrial (RA) mass occupying 80% of a severely dilated RA attached to the lateral wall (Fig A) and severe global LV hypokinesis with an ejection fraction of 20 - 25%. A TEE was then performed to further characterize this mass and showed a large (6.3 x 5.5 x 3.7 cm), heterogeneously echoreflectant, bi-lobed, and partially mobile RA mass attached to the lateral wall (Fig B,C) just below the superior vena cava and extending near the tricuspid valve annulus with sparing of the leaflets and only mild tricuspid regurgitation. At last, a chest CT scan showed a large (5.5 x 4.5 x 3.3 cm) mass which was tissue characterized as RA lipoma (Fig D). Therefore, patient underwent an uncomplicated surgical resection of the mass with partial removal of RA free wall (Fig D,E) repaired with a pericardial patch. Pathology confirmed a RA lipoma. Patient’s atrial flutter was then ablated, and patient was discharged home in stable condition. Discussion: This case illustrates an unreported cavitary giant RA lipoma inducing atrial flutter and tachycardia-mediated cardiomyopathy and emphasizes the importance of multimodality cardiac imaging in its diagnosis and management. Cardiac lipomas are rare benign tumors usually of small size and therefore mostly incidentally detected. They can rarely lead to embolization, conduction abnormalities, and flow obstruction requiring surgical resection. In this patient, pre-operative echocardiography and CT imaging were critical in the assessment of the tumor size, tissue characterization, location, motion, relation or extension to other cardiac structures, and obstruction or dysfunction of heart valves. Pre-and-intraoperative echocardiography were also essential in planning and performing the successful surgical resection of the RA lipoma.