A 73-year-old woman with a history of necrobiotic xanthogranuloma (NXG) with paraproteinemia died suddenly while hospitalized for bronchitis and congestive heart failure. At postmortem examination, myocardial lesions histologically typical of NXG were found. This is the fifth reported autopsy of a patient with NXG. In all five autopsied cases, and in two additional surgical cases, necrobiotic granulomas of internal viscera were present, and in three cases the myocardium was involved. In addition, our patient had nodular transformation of the liver, a rare lesion that was also reported in one of the previous autopsy cases with NXG.