Study On Changes Of Free Triiodothyronine(FT3) In Heart Failure Patients With Non-preserved Ejection Fraction And Its Significance

Objective:To investigate the changes of free triiodothyronine(FT3)in heart failure patients with non-preserved ejection fraction and its relationship with cardiac function.Methods:The total of 309 patients who were admitted to the Department of Cardiology of the First Affiliated Hospital of Soochow University from January 2018 to August 2019 were selected,age from 16 to 95 years old,average age was(62.71 ± 14.53)years old,including 198 males and 111 females.Among them,247 were heart failure(HF)patients with left ventricular ejection fraction(LVEF)<50%and 62 were non-heart failure patients.247 HF patients were divided into three groups according to NYHA classification:NYHA class ?(n=35),NYHA class ?(n=76),and NYHA class ?(n=136);Non-heart failure patients were used as control group(n=62).All patients were recorded gender,age,height,weight,smoking history,history of diabetes,history of hypertension,history of coronary heart disease and calculated the Body Mass Index(BMI).All patients received peripheral venous blood for N-Terminal pro-brain natriuretic peptide(NT-proBNP)test or chest pain test within 2 hours after admission,or collected the NT-proBNP or chest pain test results from the emergency laboratory of the First Affiliated Hospital of Soochow University within 2 hours before admission.The fast peripheral venous blood was taken from all patients in the early morning the next day after admission to examine high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C),and triglyceride(T G),Total cholesterol(TC),Fasting blood glucose(FBG),Creatinine,Thyroid-stimulating hormone(TSH),FT3,Free thyroxine(FT4)and other indicators.All patients underwent echocardiographic examination within 48 hours after admission,or collected the echocardiographic results of cardiac ultrasonographic examination at the First Affiliated Hospital of Soochow University within 48 hours before admission,and recorded LVEF values.To compare the differences of FT3 levels among the 4 groups,and analyze the correlation between FT3 and LVEF?NT-proBNP?NYHA classification and the predictive value of FT3 on the degree of heart failure.Result:1.The FT3 levels of the 4 groups were:control group(4.96±0.65)pmol/l,NYHA II group(4.54±0.56)pmol/l,NYHA ? group(3.97±0.70)pmol/l and NYHA IV group(3.70±0.84)pmol/l,the difference in FT3 between the four groups was statistically significant(p<0.001);2.Spearman correlation analysis in patients with heart failure showed that FT3 level was positively correlated with LVEF(r=0.153,p=0.016),and was significantly negatively correlated with the level of NT-proBNP(r=-0.482,p<0.001);There was also a significant negative correlation between FT3 level and NYHA classification(r=-0.319,p<0.001);3.The NYHA classification of HF patients was used as the dependent variable;and age,eGFR,BMI,LVEF,NT-proBNP,TSH,FT3,FT4,FBG,HDL-C,LDL-C,TG and TC were used as covariates;smoking history,gender,history of diabetes,history of hypertension,history of coronary heart disease as independent variables,Univariate logistic regression showed that history of diabetes(p=0.008),eGFR(p=0.009),LVEF(p<0.001),NT-proBNP(p<0.001),FT3(p<0.001),F BG(p=0.047),HDL-C(p=0.026)were the predictors of NYHA classification;Multivariate logistic regression showed that FT3(p=0.015),LVEF(p=0.012)and NT-proBNP(p<0.001)were independent predictors of NYHA classification.Conclusions:1.The level of FT3 in heart failure patients with non-preserved ejection fraction is lower than that in patients without heart failure,and as the degree of heart failure increases,the decrease in FT3 becomes more obvious.2.FT3 levels in heart failure patients with non-preserved ejection fraction were significantly positively correlated with LVEF,and negatively correlated with both NT-proBNP and NYHA classifications.3.Multivariate logistic regression analysis showed that FT3 was an independent factor of NYHA classification in heart failure patients,suggesting that FT3 level has a predictive value for the condition of heart failure patients with non-preserved ejection fraction.