Chronic Hemolysis Following Mitral Valve Replacement

The incidence and severity of chronic intravascular hemolysis was evaluated in a total of 41 patients following mitral valve replacement. Valve replacement was with a gamma-radiated frame-mounted aortic homograft in 21 patients and with a composite seat Starr-Edwards prosthesis, model 6310 or 6320, in 20 patients. The parameters used to assess hemolysis were hemoglobin, hematocrit, reticulocyte count, red cell fragment count, serum haptoglobin, LDH and HBD, hemosiderin in the urine and red cell survival. The degree of hemolysis was classified as mild, moderate or severe. In the prosthetic valve group 85% showed evidence of chronic intravascular hemolysis, of which a third were mild and the rest moderate. The homograft patients did not show any comparable evidence of hemolysis. Statistical analysis of the comparative figures of the parameters used to assess hemolysis in the two groups of patients revealed a significant difference (P <0.01) in hemoglobin and hematocrit and a highly significant difference (P < .001) in serum haptoglobins, hemosiderin in the urine, LDH, reticulocyte count, red cell fragment count and red cell survivals.