Reviews of postmortem reports on patients with Whipple's disease (intestinal lipodystrophy) describe gross valvular deformity in more than 50% with characteristic histological findings of macrophages containing periodic acid-Schiff-positive, diastase-resistant granules. Frequently, congestive heart failure characterizes the terminal stages. In a 58-year-old man with well-documented Whipple's disease for 5 years, gastrointestinal, joint, and pericardial involvement apparently resolved with medical therapy. However, 10 years later, severe aortic insufficiency necessitated prosthetic valve replacement, at which time gross and histological examination of the excised valve demonstrated characteristic changes of Whipple's disease. Clinical recognition of the importance of cardiac valvular abnormalities and of possible late cardiac decompensation mandates close observation of patients with Whipple's disease. Corrective operation should improve the patient's chances of survival.