A rare presentation of chest pain and syncope: massive right atrial myxoma

Abstract

Cardiac tumours, found in approximately 0.19% of unselected patients at post-mortem,1 are most frequent in women (female:male; 17:7) and are generally found in the left atrium.2 The vast majority are benign and nearly half are myxomas. Right atrial myxomas are rarer still, accounting for between 5% and 23% of all myxomas and reported through case reports and single-centre experience.3 4 Transthoracic echocardiography can identify myxomas through their classic appearance as well defined masses that are heterogeneous and are attached to the interauricular septum by a stalk. Consideration must be given to the differential diagnoses, which includes atrial thrombus, other benign tumours such as lymphangioma, leiomyoma or haemangiomas and malignant tumours such as angiosarcoma, leiomyosarcoma and metastatic deposits of systemic cancer. While transoesopheal echocardiography can be used to further characterise the nature of cardiac masses, it is an invasive procedure and is limited in characterising soft tissue masses. Cross-sectional non-invasive imaging techniques such as cardiac CT and cardiac magnetic resonance (CMR) in particular have helped further delineate the likely pathology of soft tissue masses through the description of characteristic appearances, evidence of myocardial invasion if present and involvement of extracardiac mediastinal structures. CMR is well established in evaluating such masses, allowing simultaneous imaging of the great vessels and the heart and thereby the assessment of the anatomic extent of cardiac masses. CMR provides better soft tissue contrast than cardiac CT often without the need for a contrast agent. Myxomas classically appear iso- to hypodense with T1 and hyperintense with T2 weighted imaging sequences and do enhance with contrast, allowing differentiation from the largely valvular fibroelastomas, septal lipomas, malignant sarcomas and cardiac lymphomas,5 making CMR the imaging modality of choice for cardiac mass evaluation.