A 67-year-old asymptomatic male was admitted for evaluation of his arterial hypertension. The routine echocardiographic study revealed a large tumour in the dilated right atrium. The mass appeared to arise from the posterior wall of the right atrium. After infusion of a contrast agent, the mass appeared to fill with the contrast agent, ruling out the possibility of the mass being a clot. Transesophageal study revealed a round mass arising from the posterior right atrial wall just adjacent to the extrusion of the superior vena cava. The patient subsequently underwent cardiac surgery and a cardiac tumour was excised that proved to be a cardiac myxoma. In this case we present echocardiographic images and the macro- and microscopic view of the right atrial myxoma.