Correlation Research Among Plasma BNP,QTc Interval Of Electrocardiogram And Echocardiographic Cardiac Function Indexes In Patients With Heart Failure With Preserved Ejection Fraction

Objective:Through observing the characters of plasma BNP,QTc interval and QTd of electrocardiogram and echocardiographic indexes in patients with heart failure with preserved ejection fraction(HFPEF).We investigated the correlation relationship among plasma BNP and QTc interval as well as QTd of electrocardiogram and echocardiographic indexes.Furthermore,we investigated the relationship between the severity of cardiac function and plasma BNP,ECG and echocardiographic relevant indexes in patients with HFPEF.Methods:A retrospective study was conducted to analyze 104 patients(53 men and 51 women,age:55～80)with HFPEF who were admitted to the Department of Cardiology,second affiliated Hospital of Kunming Medical University from June 1 st 2016 to October 30th 2017;selected another 80 examinees(41 men,39 women,age:60-75)from the examination center of the hospital as the control group with normal left ventricular function(NYHA cardiac function grade I).1.Basic information was collected from all candidates,such as,gender,age,height,weight,history of tobacco and wine,and underlying disease,etc.;laboratory tests were performed,such as,plasma BNP and biochemistry,etc.;12-leads routine electrocardiogram,echocardiography and other relevant tests were performed.The level of plasma BNP,QTc interval and QTd of ECG,and echocardiographic indexes of 12-leads routine electrocardiogram(such as LAD,LVDd,IVST,LVPWT,E/A ratio and PAS,etc.)were measured,recording results and analyzing the correlation relationship among plasma BNP,QTc interval of ECG and echocardiographic indexes of heart function in patients with HFPEF.2.According to the heart function of NYHA,the patients with HFPEF were divided into three subgroups:Group A:42 cases with NYHA cardiac function grade Ⅱ Group B:39 cases with NYHA cardiac function grade Ⅲ;Group C:22 cases with NYHA cardiac function grade Ⅳ.Observed the changes of the above indexes in patients with HFPEF deteriorating with cardiac function,and analyzed the correlation relationship of the severity of cardiac function in patients with HFPEF and plasma BNP,electrocardiogram,echocardiographic relevant indexes.Results:1.The body mass index,systolic and diastolic blood pressure in HFPEF group were higher than those in control group with significant difference(P<0.05);Hypertension was the main cause in HFPEF group with the percentage of 62.5%,and NYHA cardiac function grade II was the largest group with hypertension,accounting for 41.3%.2.The levels of plasma BNP,blood glucose,triglyceride,cholesterol,creatinine,uric acid and homocysteine in HFPEF group were all significantly higher than those in control group with significant difference(P<0.05).3.The values of heart rate,QT interval,QTc interval and QTd in HFPEF group were higher than those in control group with significant difference(P<0.05).4.The-values of LVDd,LAD,IVST,LVPWT and SPAP in HFPEF group were significantly higher than those in control group with significant difference(P<0.05).There was no significant difference in LVEF between the two groups(P>0.05).5.After dividing HFPEF group into 3 groups according to NYHA cardiac function,there were significant differences(P<0.05)in plasma BNP level,QTd,QTc interval and LAD among the three groups.And the plasma BNP level and QTd,QTc interval increased with the deterioration of cardiac function.6.The value of LAD in HFPEF group was positively correlated with plasma BNP level(r=0.251,P=0.010)and QTc interval(r=0.221,P=0.024)of ECG.There was no correlation relationship between other indexes of echocardiography and plasma BNP level as well as QTc interval of electrocardiogram.7.There was a positive correlation between plasma BNP level and QTc interval(r= 0.594,P<0.05)and QTd(r= 0.0.378,P<0.05)of ECG in HFPEF group.The QTc interval of ECG was also positively correlated with QTd(R=0.456,P<0.05).8.The HFPEF was the dependent variable,QTc interval as independent variables,and were performed ROC curve analysis.The results show that AUC of QTc interval diagnosed with HFPEF was 0.831,P<0.05,and there was statistically significant.When the QTc interval cut-off value was 454.16ms,the sensitivity and specificity of predictive the prevalence of HFPEF were 0.615,0.918.Conclusions:1.Patients with HFPEF often complicate with hypertension,coronary heart disease,atrial fibrillation,diabetes and other underlying disease,among which hypertension is the most important risk factor.2.With the deterioration of cardiac function in patients with HPPEF,where the level of plasma BNP and the QTc interval of ECG increase and prolong relatively.So we suggest that the level of plasma BNP and QTc interval of ECG could be used as an auxiliary index to judge the severity of HFPEF.3.The level of plasma BNP and QTc interval of ECG and echocardiographic could be used as an auxiliary index to judge the severity of HFPEF.4.When the QTc interval cut-off value was 454.16ms,the sensitivity and specificity of predictive the prevalence of HFpEF were 0.615,0.918.