Prevalence and clinical implications of abnormal thyroid hormone metabolism in advanced heart failure.

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.