Patients with advanced congestive heart failure are often severely ill and may 
experience substantial abnormalities in thyroid hormone metabolism. Thus, we 
examined this patient population to determine the prevalence and prognostic 
significance of altered thyroid hormone concentrations, the course of thyroid 
abnormalities in congestive heart failure survivors, and the potential 
relationship of thyroid abnormalities to overall metabolic rate. Our results 
indicate that thyroid hormone metabolism (ie, the triiodothyronine to reverse 
triiodothyronine ratio) is altered in a majority of patients with advanced 
congestive heart failure and is an independent predictor of mortality. Currently 
a study is underway that will provide further evidence for the mechanisms 
involved in congestive heart failure and abnormal thyroid hormone metabolism.