Correlation Between Serum Angiopoietin-like Protein 4 And Left Ventricular Remodeling After Acute Myocardial Infarction

Objective: The morbidity of acute myocardial infarction(AMI)is increasing and more and more younger people have AMI.Although timely,standard and effective reperfusion therapy and drug therapy after AMI,thus less major adverse cardiovascular events and decreasing early mortality rate resulting from it,left ventricular remodeling after AMI still has an adverse effect on heart function and short and long-term prognosis,and what's more,is closely related with early ventricular aneurysm formation and cardiac rupture,late ventricular dilation and heat failure.Adipose tissue,not only involves in energy metabolism,but also as an active endocrine organ secrets a number of adipokines that take part in many physiologic and pathophysiologic process including glucose and lipid metabolism and inflammation and affect atherosclerosis and left ventricular remodeling via different ways.Angiopoietin-like protein 4(ANGPTL4),a kind of circulating protein,belonging to the ANG-like family,classified as an adipokine as well,predominantly expresses in adipose tissues and liver.It has been demonstrated that ANGPTL4 plays an important role in fighting against atherosclerosis and modulating inflammation,but no research on ANGPTL4 and left ventricular remolding.This study aims to observe the serum ANGPTL4 levels in patients with AMI,and determine the relationships between serum ANGPTL4 level and the risk factors of coronary artery disease and left ventricular remodeling.Methods: 81 patients with ST-segment elevation acute myocardial infarction treated in No.2 Affiliated Hospital of Hebei Medical University from Dec.2014 to Sept.2015 were enrolled in this study.The diagnosis of AMI were made according to the WHO Acute Myocardial Infarction criteria.The following conditions were excluded: non-ST-segment elevation acute myocardial infarction,previous myocardial infarction,previous heart failure,valvular heart disease,cardiomyopathy,myocarditis,congenital heart disease,poorly controlled hypertension for a long time and other diseases accounting for left ventricular remodeling,further more malignant tumor,infectious disease,autoimmune disease,severe hepatic and renal dysfunction.All patients with AMI were admitted within 24 hours after symptoms onset.Some of them received thrombolytic therapy or percutaneous coronary intervention(PCI)with indications and all patients were given standard drug therapy if had no contraindications.The fasting median cubital vein blood samples were drawn within 48 hours after symptoms onset to measure serum ANGPTL4 levels by enzyme-linked immunosorbent assay(ELISA).Echocardiograms were performed within 48 hours after symptoms onset and at 6 months follow-up.Left ventricular end-diastolic volumes(LVEDV)and left ventricular ejection fraction(LVEF)were measured by the Simpson method.All patients with AMI were divided into left ventricular remodeling group and no left ventricular remodeling group according to LVEDV within 48 hours after symptoms onset(LVEDV1)and at 6 months follow-up(LVEDV2).Left ventricular remodeling was defined as an at least 10% [(LVEDV2-LVEDV1)/LVEDV1]increase in LVEDV.35 healthy persons who had physical examinations in No.2 Affiliated Hospital of Hebei Medical University were selected as the control group.The fasting median cubital vein blood samples were drawn within 24 hours after enrollment to measured serum ANGPTL4 levels of them by ELISA as well.Take a record of the clinical data of all subjects in detail,including gender,age,height,weight,the history of hypertension,hyperlipemia,impaired glucose metabolism,smoking and family history of cardiovascular diseases and drug therapy of patients with AMI and so on.All participants routinely underwent fasting blood test,chest X-ray,echocardiogram and electrocardiogram(ECG).The normality test of measurement data were conducted firstly.Normally distributed continuous variables were presented in form of mean±standard deviation((?)±s).The differences between means of two groups were evaluated with t-test.Count data were presented in form of percentage.The differences between percentages of two groups were evaluated with Chi-square test.Correlations between 2 variables were assessed by using Pearson correlation analysis.Associations between left ventricular remodeling and clinical/ biochemical parameters(including age,gender,body mass index(BMI),the presence of hypertension,blood lipid,blood glucose,smoking and serum ANGPTL4 levels)were analyzed by Logistic regression analysis.All P-values were two-tailed and a level of P<0.05 was considered statistically significant.Statistical analysis were performed using SPSS 22.0 for Windows.Results:86 patients with AMI were enrolled first,while 2 patients of them died and 3 patients were loss to follow-up.Actually 81 patients were enrolled at last,59 of which were male.32 patients were divided into left ventricular remolding group.1 There were no differences in age,gender,BMI,serum triglycerides(TG)level,serum total cholesterol(TC)level,serum high-density lipoprotein(HDL)level,serum low density lipoprotein(LDL)level,fasting plasma glucose(FPG),the prevalence of hypertension,hyperlipemia,impaired glucose metabolism,history of smoking,and medication between left ventricular remodeling group and no left ventricular remodeling group.Patients with anterior myocardial infarction were more common in left ventricular remolding group(P<0.01).2 Serum ANGPTL4 levels of persons in the control group(38.82±5.19 ng/ml)were high compared with that of patients in left ventricular remodeling group(18.77±3.50ng/ml)and no left ventricular remodeling group(21.13±5.23 ng/ml,P<0.01).There was significant difference in serum ANGPTL4 levels of patients between left ventricular remodeling group and no left ventricular remodeling group(P<0.05).3 Serum ANGPTL4 levels were not correlated with gender,age,BMI,serum TG levels,serum TC levels,serum HDL levels and serum LDL levels in all patients with AMI(P>0.05).FPG showed a negative correlation with serum ANGPTL4 levels(r=-0.838,P<0.01).4 There were no significant differences between left ventricular remodeling group and no left ventricular remodeling group in LVEDV(100.83±12.39 ml vs.101.97±12.15 ml,P>0.05)and LVEF(52.70±8.94% vs.54.00±8.08%,P>0.05)within 48 hours after symptoms onset.At 6 months after AMI,LVEDV of patients in the remodeling group was 114.85±14.02 ml,LVEDV of patients in the non-remodeling group was 102.91±13.35 ml,while LVEF of patients in the remodeling group was 50.77±8.61%,and LVEF of patients in the non-remodeling group was 53.13±8.79%.The changes of LVEDV and LVEF of patients in the remodeling group were 14.03±3.71 ml and-1.93±2.31% respectively,while the changes of LVEDV and LVEF of patients in the non-remodeling group was 0.94±5.57 ml and-0.87±2.16% respectively.5 Serum ANGPTL4 levels of patients in the remodeling group were significantly negatively correlated with ?LVEDV(r=-0.831,P<0.01),and positively correlated with ?LVEF(r=0.375,P<0.05).6 In Logistic regression analysis of all patients with AMI,only serum ANGPTL4 level was significantly associated with left ventricular remodeling(OR=0.602,P<0.01).Conclusion:Serum ANGPTL4 levels of patients with AMI decrease remarkably compared with healthy persons.Serum ANGPTL4 levels of patients with left ventricular remodeling after AMI are significantly lower than that of patients without left ventricular remodeling after AMI.ANGPTL4 may be a protective factor in the process of AMI and left ventricular remodeling after AMI.