Prosthetic mitral valve induced chronic intravascular hemolysis in comparison to the repaired mitral valve

Prosthetic mitral valve induced chronic intravascular hemolysis was compared to the repaired mitral valve induced hemolysis by postoperative serum lactate dehydrogenase (LDH) level in 11 mechanical valves (Edwards TEKNA), 4 bioprostheses (3 Carpentier Edwards bovine pericardial and one Hancock II porcine) and 10 repaired mitral valves. Postoperative LDH level of mechanical valve, bioprosthesis and repaired mitral valve was 534 ± 78 IU/L, 455 ± 73 IU/L and 407 ± 45 IU/L, respectively. Postoperative LDH level of mechanical valve increased from preoperative level of 534 ± 78 IU/L significantly (p<0.0389), was markedly high compared to the postoperative LDH level of repaired valve (p<0.0004), and increased in the patients with atrial fibrillation compared to those with sinus rhythm. Hard structure of mechanical valve may induce higher level of subclinical mechanical hemolysis compared to soft structure of repaired mitral valve and bioprosthesis.