We report, to the best of our knowledge, the first case of fatty infiltration involving a semilunar cardiac valve. A non-obese 79-year-old man had an echogenic mass in the right coronary cusp on transesophageal echocardiography attributed to fatty infiltration. Fat in this location is extraordinary, and may arise from pluripotential interstitial myofibroblast-like cells, perhaps due to valvular injury.