When is a mass not a mass? An unusual presentation of prominent crista terminalis

Abstract

This case report describes a patient in whom echocardiography showed borderline left ventricular hypertrophy and a mass adjacent to the right atrial wall. This naturally caused some concern as the differential diagnoses included that of a right atrial myxoma and further investigations were organised. A subsequent cardiac MRI revealed this thickening to be a prominent crista terminalis. The crista terminalis is a variant of normal anatomical structures within the right atrium, which mimics an atrial mass.