Three cases of cardiac valve replacement for Libman-Sacks endocarditis and their long-term follow-up are described. From the review of the literature, an additional nine patients who required cardiac valve replacement are studied. Steroids probably increase the incidence of valve incompetence, but most patients presumably die of other associated organ involvement before undergoing a cardiac operation. Operation is indicated because of change in the intensity or character of the murmur, and a new murmur with resultant, resistant congestive cardiac failure. Both the aortic and mitral valves should be explored. Valve reconstruction in these young patients, with the expectation of avoiding prosthetic valve dysfunction and repeat operation, is not possible. Bioprosthetic valve replacement may be preferable, since it eliminates the need for anticoagulation during steroid treatment. Overall mortality was 25%.