Quantitative Analysis Of Left Ventricular Layer-specific Strain Using 2-Dimensional Speckle Tracking Imaging In Patients With Atrial Fibrillation

Objective As one of the most common arrhythmias in clinical practice,atrial fibrillation significantly increase the incidence of stroke and heart failure,affecting the life qualities,is one of the most important lethal and disabling diseases in China [1].Atrial fibrillation attacks will affect the effective ejection function of atrium,and left atrium in the late diastole can not take the initiative to contract for the left ventricular filling,Rapid and irregular ventricular rate impair the systolic function and compliance [2],thus further affecting the left ventricular local and overall function.The quantitative evaluation of local and global function of left ventricular myocardium is more and more concerned by imaging diagnosis,but the stratified analysis of left ventricular myocardium is lacking in-depth study.This study aims to take patients with atrial fibrillation as study object to explore the left ventricular myocardium stratification strain changes by 2D-STI.Methods Atrial fibrillation without heart failure group 48 cases,atrial fibrillation with heart failure group 32 cases,normal control group 40 cases.The Echo PAC 113 software is used to analyze two-dimensional dynamic images after routine measurement and acquisition of images.peak longitudinal strain(PLS)and total thickness of the whole of the endocardial,epithelium and epicardial myocardium in the left ventricular 18 segments were obtained.Conventional ultrasound measurements: Simpson's measurements of left ventricular ejection fraction(LVEF),left atrial diameter(LAD),left ventricular end diastolic diameter(LVEDD),left ventricular end systolic diameter(LVESD)and early diastolic mitral flow velocity(E ')and ventricular septal mitral annulus velocity(e')ratio E / e '.Segmental Stratification Strain: Endocardial systolic peak longitudinal strain(PLSEndo),Middle systolic peak longitudinal strain(PLSMid),Epicardial systolic peak longitudinal strain(PLSEpi),Eighteen segments in the left ventricular systolic.The overall stratification: Endocardial systolic global peak longitudinal strain(GPLSEndo),Middle systolic global peak longitudinal strain(GPLSMid),Epicardial systolic global peak longitudinal strain(GPLSEpi)and the whole myocardium in the subconjunctival myocardium Systolic peak longitudinal strain(GPLS).Results 1?Comparison of conventional echocardiography parameters Compared with the healthy group,there was no obvious statistical difference about left ventricular end diastolic diameter in atrial fibrillation group;also there was no obvious statistical difference about left ventricular end systolic diameter and left ventricular ejection fraction in atrial fibrillation group,but the left atrium diameter and the ratio of early diastole mitral valve flow low velocity(E)/ the ventricular septal mitral annulus velocity(e')was different(P <0.05).As to the atrial fibrillation with heart failure group,left atrial diameter,left ventricular end diastolic(systolic)diameter,left ventricular ejection fraction and E/e' was significantly different with the control group.(P <0.01)2?Segmental Stratification Strain Comparison: Compared with the control group,Systolic peak longitudinal strain of endocardial,Epicardial myocardium systolic peak longitudinal strain(PLSEndo),Middle systolic peak longitudinal strain(PLSMid)of the systolic heart in the medial segment,the middle segment and the pericardium of the atrial fibrillation group were obviously reducer than those in the healthy group(P <0.05).The peak longitudinal strain(PLSEpi)of the myocardium in the outer layer was decreased(P <0.05).Compared with atrial fibrillation group,the peak longitudinal strain(PLSEndo),the systolic peak longitudinal fixation(PLSMid)of the medial segment,the middle segment and the apical segment of the subendocardial,The peak longitudinal strain(PLSEpi)of the systolic myocardium in the atrial fibrillation with heart failure group were reducer,There was a big difference(P <0.05).3?The overall stratification of the comparison: Compared with the control group,the longitudinal strain(GPLSendo,GPLSmidi,GPLSepi)and the left ventricular whole placenta(GPLS)of the inner,middle and outer layers of the atrial fibrillation group were obviously reduced,There was a big difference(P <0.05).Compared with atrial fibrillation group,the longitudinal strain(GPLSendo,GPLSmidi,GPLSepi)and full-thickness PLS(GPLS)of the left ventricle in the atrial fibrillation with heart failure group were significantly lower,and the atrial fibrillation group Statistically significant(P <0.05).The GPLS of the left ventricle from the inner to the outer myocardium was decreased in all subjects.4.The ROC curve analyse of left ventricular full-thickness overall longitudinal strain myocardial detection in patients with atrial fibrillation.Left ventricular myocardial full-thickness overall longitudinal strain consolidation area under the curve of patients with atrial fibrillation is 84.9%,when the truncation point of 21.38%,77.7% sensitivity and 72.5% specific degrees.Conclusion Stratified Strain Technique can quantitatively evaluate the overall and local function of left ventricular myocardium in patients with atrial fibrillation,and has certain clinical application values.