The Changes Of Left Atrial Structure And Function In Patients With Preserved Ejection Fraction Heart Failure

Objective : The pathogenesis of heart failure is that various etiologies lead to myocardial injury,leading to structural and functional changes,which in turn lead to impaired ventricular pumping and/or filling function.Found in the actual clinical work,although there have been a part of patients symptoms and/or signs of heart failure,but the left ventricular ejection fraction remained in the normal range,this type of heart failure is referred to as ejection fraction retained by heart failure.Recent studies found that changes in the structure and function of the left atrium plays an important role in the occurrence and development of cardiovascular disease,but did not make the analysis and report of patients with preserved ejection fraction heart failure of left atrial structure and function.This paper aims to study the changes of the left atrial structure and function of the patients with heart failure(LVEF% > 50%)by applying two-dimensional speckle tracking echocardiography to study the strain and strain rate indicators,the relationship between the left atrial strain and strain rate index with the global longitudinal strain peak of left atrial ventricular(LV-GLS%),the ratio of the peak veloctites of mirtral inflows in early diastole and the peak velocity of mitral annular interventricular septal ring in early diastole(E/e')and N terminal B type blood natriuretic peptide(NT-proBNP)level.Material and Methods: The heart failure group enrolled between January 2017 and November 2017 in our hospital circulation department and treatment of patients with 30 people,who meet the 2016 European Society of Cardiology(ESC)in thediagnosis and treatment of acute and chronic heart failure guidelines about ejection fraction retained heart failure diagnostic criteria,and N terminal b-type natriuretic peptide original(NT-proBNP)> 300 pg/ml(including hypertension,diabetes,coronary heart disease,paroxysmal atrial fibrillation).All the participants were sinus rhythm at the time of ultrasonic examination.Except LVEF<50% and all kinds of congenital heart disease,heart valvular disease,cardiomyopathy,pericardium,persistent atrial fibrillation,hyperthyroidism,hypothyroidism,tumor and other patients.According to the cardiac function classification method of New York Heart Association(NYHA),HFpEF was divided into A group with impaired heart function(NYHA ? Level)and group B with severity impaired cardiac function(NYHA ? and ? level).28 subjects were selected as healthy control group who exclude cardiopulmonary diseases trough the electrocardiogram(ECG),echocardiography and biochemical examination.There was no statistical difference in sex and age between the two groups.Record the basic clinical data,take the admission day or second days fasting venous blood test,use echocardiography test,strain and strain rate evaluation of two groups of left atrium diameter,left ventricular parameters,the global longitudinal strain peak of left atrial and left ventricular(LA-GLS% ? LV-GLS%)and strain rate,left ventricular global circumferential strain peak(LV-GCS%)and strain rate.The statistical analysis was carried out with SPSS 20.0 software,and the difference was statistically significant when p < 0.05.Results:1.Comparison of general clinical data: systolic blood pressure(SBP),heart rate(HR),NT-proBNP,creatinine(Cr),urea nitrogen(BUN)and uric acid(UA)in HFpEF group were higher than those in the control group.Hemoglobin(Hb)and glomerular filtration rate(eGFR)were both smaller than the control group,and the difference was statistically significant.2.The comparison of echocardiography parameters: There was no significant difference between the two groups of left ventricular ejection fraction(LVEF%)?HFpEF group of left ventricular fractional shortening(FS%),left ventricular strokevolume(SV),peak velocity of mitral annular interventricular septal ring in systole(S '),peak velocity of mitral annular interventricular septal ring in early diastole(E '),peak velocity of mitral annular interventricular septal ring in late diastole(A ')is less than the control group(p < 0.01);left atrium anterior and posterior diameter(LA-D),left atrium transverse diameter(LA-T),left atrium long diameter(LA-L),the ratio of the peak veloctites of mirtral inflows in early diastole and the peak velocity of mitral annular interventricular septal ring in early diastole(E/e'),left ventricular interventricular septum thickness(IVSD),left ventricular posterior wall thickness(LVPWD),the ascending aorta diameter(AAOD)and the main pulmonary artery diameter(MPA)are higher than the control group(p < 0.01);right atrium transverse diameter(RA-T),right atrium long diameter(RA-L)are also bigger than the control group(p < 0.05),the difference was statistically significant.3.Strain and strain rate comparison: HFpEF group the global longitudinal strain of left ventricular and left atrial(LV-GLS%,LA-GLS%)and strain rate,the left ventricular global circumferential strain(LV-GCS%)and the strain rate are less than the control group,the difference was statistically significant.There was no significant difference in LVEF% between HFpEF A group and group B.However,the global longitudinal strain of left atrial(LA-GLS%),left atrial systolic mean strain rate(LA-mSRs)and left atrial late diastolic mean strain rate(LA-mSRa)in group A were higher than that in group B,the difference was statistically significant.The early diastolic average strain rate of the left atrium(LA-mSRe)in group A and group B was not statistically significant,but overall presented HFpEF B group downward trend than A group.4.Correlation analysis: The global longitudinal strain of left atrial(LA-GLS%)and left atrial systolic mean strain rate(LA-m SRs)were negatively correlated with LV-GLS%? NT-proBNP and the ratio of the peak veloctites of mirtral inflows in early diastole and the peak velocity of mitral annular interventricular septal ring in early diastole(E/e')';left atrial late diastolic mean strain rate(LA-mSRa)was positive related to LV-GLS%? NT-proBNP?E/e'.All of these were statistically significant.Conclusion: The left atrial diameter was enlarged and the left atrial function of reservoir,conduit and pump were impaired in the patients with preserved ejection fraction heart failure.Left atrial global longitudinal strain(LA-GLS%)and systolic strain rate(LA-mSRs)and late diastolic strain rate(LA-mSRa)has certain clinical value in judging severity of HFpEF.