Chronic haemolysis occurring in patients following cardiac surgery.

Iatrogenic aberrations of serum enzyme activity

“…Five of the nine patients with severe aortic valve disease manifested an elevated total LDH activity and predominance of LDH1 and LDH2 by electrophoresis before attempted surgical correction of the valvular disorder. Similar findings have been reported by others (10,11). Data thus far accumulated suggest that all patients with prosthetic valves and a significant number of patients with uncorrected severe hemodynamic abnormalities have a chronic, usually compensated, intravascular hemolysis related to damaged erythrocytes.…”

“…As indicated by Bell and his associates (11) it seems unlikely the hemolysis associated with the prosthetic device is solely attributable to tim presence of the foreign material. Valve incompetence and a turbulent jet effect may appear to be the primary factors in the production of hemolysis.…”

Red Cell Survival after Heterograft Valve Surgery

“…This contrasts with reports of artificial prostheses. Bell et al (1967), in a series of 27 patients with artificial valve prostheses, found evidence of baemolysis in 20, while Brodeur et al (1965) demon-BRITISH MEDICAL JOURNAL 807 strated reduced Ti 5"Cr-labelled red cells in 8 of his 12 patients with Starr-Edwards valve prostheses, the range of values obtained being 9 to 23 days, with a mean of 18 days. Of these 12 patients 7 had normally functioning prostheses and four of them were found to have a reduced Ti for 5'Cr-red cells (18 to 23 days).…”

“…Intravascular haemolysis is a frequent complication of prosthetic valve replacement (Brodeur et al, 1965 ;Rubinson et al, 1966;Bell et al, 1967), and in a significant proportion of cases frank haemolytic anaemia occurs, particularly with incompetent prostheses (Sayed et al, 1961 ;Marsh, 1964;Stevenson and Baker, 1964). Random destruction of red cells due to valve turbulence and shearing forces created by a regurgitant flow of blood form the most likely basis for the haemolysis, and this theory has recently received experimental support (Nevaril et al, 1968).…”

Serum Haptoglobin and Lactic Dehydrogenase during Haemodialysis

“…In another clinical situation, that of patients with cardiac valve prostheses, subclinical haemolysis has been demonstrated by a fall in serum haptoglobin [2,6], despite normal haematocrit values and, in most cases, absence of reticulocytosis. Half life of the red cells as measured by 51Cr was reduced in 14 out of 20 patients [5].…”