Even mild changes in free thyroxine could influence the degree of heart failure measured by its biological surrogates

Abstract

Patients with fT4 in the range 11.9-14.6 pmol/1 had significantly lower NT-proBNP, than those with fT4< 11.8 and those with fT4 over 14.6 pmol/1. Thus, the severity of heart failure seems to be also influenced by only mild deviations of fT4 concentrations from optimal levels.