We report 2 cases of severe intravascular hemolysis after mitral valve repair using a Duran annuloplasty ring. In both patients residual mitral regurgitation was present, hemolysis was severe enough to warrant a second operation, and hemolysis ceased immediately after the second operation. We believe that a high-velocity regurgitant jet directed toward the cloth-covered annuloplasty ring was responsible for the hemolysis in both patients.