[Selenium deficiency associated with cardiac dysfunction in three patients with chronic respiratory failure].

We encountered three patients with chronic respiratory failure who had heart failure of cardiac arrhythmias and low levels of serum selenium. All three had tracheostomies and had received long-term parenteral nutrition that had not included selenium. All three also had refractory cardiac dysfunction, which was manifested in edema, heart failure, and various tachycardias. We suspected that selenium deficiency had caused their cardiac dysfunction. Serum selenium concentrations were found to be much lower than normal in all three, so 100 micrograms/day of selenium was administered in addition to their tube feedings. Cardiac function improved after replacement of selenium. These cases show the need for preventing selenium deficiency in patients with chronic respiratory failure during long-term administration of parenteral nutrition.