RESUMO
The problem of haemolysis was studied in 244 patients with one or two prosthetic heart valves: 232 of these patients had normal valve function as assessed by clinical examination, radioscopy and echocardiography; 112 patients had a Bjork-Shiley (BS) prosthesis, 25 in the aortic position (BSA), 71 in the mitral position (BSM) and 16 in both aortic and mitral positions (BSA + M). These patients were operated between July 1979 and January 1981. One hundred and twenty other patients had Saint Jude medical (SJM) prostheses; 48 in the aortic position (SJMA), 44 in the mitral position (SJMM) and 28 in both aortic and mitral positions (SJMM + A). These patients were operated between January 1982 and July 1983. Twelve patients (operated between 1977 and 1984) had prosthetic valve dysfunction confirmed by angiography or anatomically (SJM = 7); BS = 5). The plasma haemoglobin concentration (pHb) was used as the reference: it was measured by spectrophotometry with a sensitivity of 0.5 mg/100 ml. There was no significant difference the SJM and BS groups at surgery (BS: 4.62 mg/100 ml; SJM: 4.31 mg/100 ml). In the absence of prosthetic valve dysfunction, haemolysis was significantly greater (p less than 0.001) in the SJM (8.28 mg/100 ml) than in the BS (3.08 mg/100 ml). No statistical correlation was observed with the severity of cardiac disease, the aortic or mitral position of the prostheses or with the number of prostheses. Haemolysis was subclinical in all cases. When haemodynamically significant prosthetic valve dysfunction was present, haemolysis was inconstant in BS prostheses (2 out of 5 cases) despite major haemodynamic disturbances in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)
