Urinary iron excretion in valvular heart disease and after heart valve replacement.

Urinary iron excretion and other aspects of iron metabolism were studied in patients with valvular heart disease before and after valve replacement with heterografts or Starr-Edwards prostheses. Eighty-one per cent of preoperative patients had increased daily urinary iron excretion (0.14-2.2 mg./24 hours) and 61 per cent had a reduced 51Cr survival time. Serum iron levels were low in two patients but iron-deficiency anemia was not observed. Fifty-three per cent of bone marrow aspirates had reduced or absent storage iron. Patients with normally functioning heterografts had no hemolysis and urinary iron excretion decreased exponentially with time until normal values were reached in 6-10 months after surgery. Calculated iron loss over a 6-month postoperative period varied from 11 to 360 mg. Serum iron levels and results of ferrokinetic studies returned towards normal, as did marrow iron stores. Seven patients (78%) with