A 60 year-old male presented with abnormal systolic heart murmur. Transthoracic echocardiogram revealed right ventricular (RV) hypertrophy and mosaic jet in the RV outflow tract. RV catheterization revealed significantly pressure gradient between the RV and the pulmonary artery. Enhance ECG-gated multislice CT was performed and an axial source image in end-diastole revealed RV myocardial hypertrophy and remarkable hypertrophy of the moderator band. Multiplanar reconstruction images in end-systole revealed hypertrophic anomalous muscle bundles in the RV and significant narrowing of the RV outflow tracts and a post-stenotic dilated pulmonary trunk. In volume rendered images, in end-systole, the lumen of RV outflow tract revealed severe stenosis compared with that in end-diastole and he was diagnosed with double chamber RV.