关键词: 心力衰竭, 正常甲状腺病态综合征, 非甲状腺疾病综合征, 低T3综合征, 预后

Abstract: Background　Abnormal metabolism of thyroid hormones is involved in the pathological processes of chronic heart failure （CHF）.However，there are few studies on the long-term prognosis of CHF patients with euthyroid sick syndrome （ESS） in China.Objective　To study the effects of ESS on long-term prognosis of CHF patients.Methods　This study included 304 CHF patients，who were hospitalized in Department of Cardiology，Wusong Hospital of Zhongshan Hospital，Fudan University from January 2017 to June 2019.The general information and laboratory indicators were compared between those with T3 level<1.01 nmol/L and/or FT3 level<3.28 nmol/L（ESS group） and those with T3 level of 1.01-2.48 nmol/L and FT3 level of 3.28-6.47 nmol/L（normal thyroid function group）.Post-discharge follow-up was conducted until June 2020 with all-cause death （including death due to heart failure and non-cardiac death）as the primary endpoint，and readmission due to heart failure as the secondary endpoint.Thyroid hormones 〔T3，FT3，thyroxine （T4），free T4 （FT4），and thyroid stimulating hormone （TSH）〕，B-type natriuretic peptide （BNP），and left ventricular ejection fraction （LVEF）of the survivors were compared with those of the deceased due to all causes，the deceased due to heart failure，and the deceased due to noncardiac causes.The readmission rate due to heart failure，heart failure mortality rate，and all-cause mortality rate between the ESS and normal thyroid function groups were compared，and Kaplan-Meier survival curves were plotted.Cox regression analysis was used to identify the factors associated with heart failure death and all-cause death.Results　There were 164 patients in the ESS group and 140 patients in the normal thyroid function group.The distribution of NYHA class showed significant difference between the two groups （P<0.05）.The mean levels of T3，FT3，FT4，TSH，albumin，and hemoglobin，and LVEF were lower，and mean levels of BNP，C-reactive protein，and creatinine were higher in the ESS group （P<0.05）.In a median follow-up period of 25.7 （interquartile range 14.2） months，there were 46 all-cause deaths （32 due to heart failure，and 14 due to noncardiac causes） and 258 survivors（115 were readmitted at least once for heart failure）.The survivors showed higher mean levels of T3，FT3 and LVEF and lower mean level of BNP compared with the deceased due to all causes，or the deceased due to heart failure （P<0.05）.Those with ESS had higher heart failure readmission rate，heart failure mortality rate，and all-cause mortality rate than those with normal thyroid function（P<0.05）.Kaplan-Meier survival analysis showed that the heart failure mortality rate and all-cause mortality rate of the ESS group were higher than those in the normal thyroid function group （P<0.016）.Cox regression analysis showed that age 〔HR=1.056，95%CI（1.009，1.105）〕，FT3 〔HR=0.564，95%CI（0.325，0.976）〕，hemoglobin 〔HR=0.955，95%CI（0.932，0.980）〕，and LVEF〔HR=0.980，95%CI（0.961，1.000）〕 were associated with heart failure death in CHF patients （P<0.05），and age 〔HR=1.055，95%CI（1.019，1.093）〕，hemoglobin〔HR=0.964，95%CI（0.944，0.984）〕，and LVEF 〔HR=0.979，95%CI（0.963，0.994）〕 were associated with all-cause death （P<0.05）.Conclusion　CHF patients with ESS had poor renal and liver function.Their heart-failure mortality rate and all-cause mortality rate were higher，and their prognosis was poorer than those of CHF patients without ESS.T3 and FT3 levels reflected the severity and prognosis of CHF patients.

Key words: Heart failure, Euthyroid sick syndrome, Nonthyroidal illness syndrome, Low T3 syndrome, Prognosis