An 83-year-old male patient with high-degree AV block. In the short-axis image of the left ventricular outflow tract, the density of the right fibrous trigone (RFT) was measured with a free-hand ROI as a mean of 22.7 HU. IVS, interventricular septum; LA, left atrium; LV, left ventricle; LW, lateral wall; M-AL, mitral anterior leaflet; RV, right ventricle.