ABSTRACT
Objective To investigate the relationship between peripheral blood thyroxine levels and cardiac function in elderly patients with chronic heart failure.Methods Seventy patients with chronic heart failure admitted into our hospital from January 2016 to December 2017 were enrolled as the study group,and 70 healthy subjects were collected as the control group.Left ventricular ejection fraction(LVEF)and serum thyroxine levels were measured in both groups.Results LVEF,serum levels of total triiodothyronine(TT3)and total thyroxine(TT4)were lower in the study group than in the control group[(37.3±2.4)％ vs.(58.5 ± 5.3) ％,(87.4 ± 8.7) mmol/L vs.(120.8±10.4) mmol/L,(8.6±1.7)mmol/L vs.(10.1 ± 1.3)mmol/L,t =30.486,20.609 and 5.864,P =0.000].LVEF,TT3 and TT4 in patients with grade lⅡ 、grade Ⅲ and grade Ⅳ Cardiac insufficiency were [(42.3±2.2)％、(37.9± 1.0)％ and(31.8±1.5)％,(104.2± 15.4) mmol/L、(89.7±4.6) mmol/L and(72.0±7.2)mmol/L,(9.3± 1.8)mmol/L、(8.8± 1.3) mmol/L and (8.1 ± 0.9) mmol/L]respectively.Serum levels of TT3 and TT4 and LVEF steadily declined as cardiac dysfunction grew more severe in patients with chronic heart failure(P =0.000).Conclusions Patients with chronic cardiac insufficiency are often combined with euthyroid sick syndrome,and serum levels of TT3 and TT4 can indicate the degree of abnormal cardiac systolic function.Therefore,low serum levels of T3 and T4 can be used as indicators for poor prognosis in patients with chronic heart failure.