MOBILE RIGHT HEART MASS – THROMBUS OR MYXOMA

Abstract

INTRODUCTION: Right heart mass is a rare and incidental finding. It is important to diagnose right heart mass because each differential can lead to different management and outcome. 

CASE: A 78-year-old man with triple vessel disease, end stage renal failure, diabetes mellitus and hypertension presented to the emergency department with complaints of exertional dyspnea for two weeks. Electrocardiography shows normal sinus rhythm. Transthoracic echocardiography (TTE) showed an ovoid mass moving from right atrium (RA) to right ventricle (RV) and continues to the inferior vena cava. The (RA) and (RV) appear dilated. Computed tomography pulmonary angiogram (CTPA) was done twice. There was no pulmonary embolism from first CTPA, but subsequent scan revealed filling defects in pulmonary artery supplying the right lower lobe. The patient was started on subcutaneous enoxaparin in the ward and discharged well with oral anticoagulant.

DISCUSSION: The classic echocardiographic features to differentiate myxoma from atrial thrombus are that the thrombi are irregular, laminated and immobile. However this description holds true only for in situ atrial thrombi and not for secondary atrial thrombi. Secondary atrial thrombi are usually from peripheral veins such as IVC and are hence mobile. They are often referred to as clot in transit (CIT) as they are on their way to pulmonary arteries. They are described as spherical, grapelike, ovoid mass moving within the RA. When large, they may prolapse through RV and appear free floating with no attachment site. 

CONCLUSION: In this patient, features favoring RA thrombus are history of three vessel disease (thrombus occlusion) and abnormal attachment of mass (IVC-RA junction).