High serum chromium levels after cardiac valve replacement: Clinical significance and metabolic effects

Abstract

Serum and red blood cell concentrations of the trace elements chromium and manganese were determined in 66 patients who underwent cardiac valve replacement and in 40 control subjects. Patients with a Starr-Edwards metallic ball prosthesis had serum chromium levels of 2.54 ± 0.20 ng/ml (mean ± standard error of the mean), exceeding widely the Normal limits (0.43 ± 0.03 ng/ ml, p < 0.001). The red cell chromium content in these patients (9.9 ± 0.4 ng/ ml) was only 15 percent higher than control values (p < 0.05). Patients without evidence of prosthetic valve incompetence had a significant decrease in serum chromium toward normal levels during the postoperative period (p < 0.001). This decrease appeared to be delayed and reduced in patients with a perlprosthetic leak. Chromium levels in patients with a Starr-Edwards plastic ball or Björk-Shiley prosthesis did not differ significantly from control values. There was no significant difference in manganese levels between the groups. To study metabolic effects of changes in serum chromium, fasting cholesterol, triglyceride and glucose plasma concentrations were determined in 27 patients with a Starr-Edwards metallic ball prosthesis and in 29 patients with a Starr-Edwards plastic ball or Björk-Shiley prosthesis before and after valve replacement. In both groups, an increase In both cholesterol and triglyceride concentrations was observed regardless of the presence or absence of elevated serum chromium levels. Glucose concentrations remained unchanged after surgery. It is concluded that (1) elevation of serum chromium levels does not appear to cause a decrease of fasting lipid and glucose concentrations; and (2) there is no evidence that in the sample of patients studied a chromium deficiency may play an important role in the development of elevated lipid and glucose levels.