An Egg-Shaped Cyst of the Right Interventricular Septum

A completely asymptomatic 60-year-old man presented for a preventive calcium score screening.ECG-gated non–contrast-enhanced cardiac computed tomography showed a noncalcified hypodense oval mass in the right ventricle with a spontaneously hyperdense wall measuring 19×17 mm (Figure 1A). Echocardiography was performed and found a 16×18 mm egg-shaped hypoechoic mass with regular hyperechoic borders, suggestive of a cyst appended to the interventricular septum. Although he never traveled outside Western Europe, a hydatic cyst was suspected and a follow-up strategy was decided.Figure 1. Initial ECG-gated nonenhanced cardiac computed tomography performed for calcium scoring, axial …