Clinical Application Of Two-dimensional Speckle Tracking Echocardiography In Evaluating Left Atrial Function And Synchrony In Patients With Metabolic Syndrome

Objective: Evaluation of the effect of metabolic syndrome on left atrial function and synchrony by two-dimensional speckle tracking echocardiography,and to understand the changes in function and synchrony of LA in MS patients.Methods: The subjects were all from 2016-2017 years of health check-ups at the age of 40~70 in a community in Shenyang.According to the 2013 edition of the guidelines for the prevention and control of type 2 diabetes in China,the subjects were divided into two groups: case group(group MS)included 78 patients with MS,and healthy control group(group Normal)included 48 healthy persons with matched age and sex.According to the standard of diastolic dysfunction,the case group was divided into two subgroups: normal diastolic function group(group MS/DD-),diastolic dysfunction group(group MS/DD+).The following parameters were obtained and analyzed by echocardiography.1.Parameters of conventional echocardiography : left atrial anteroposterior diameter(LAD),left ventricular end diastolic dimension(LVEDD),interventricular septum thickness(IVST),left ventricular posterior wall thickness(LVPWT),left ventricular relative wall thickness(RWT)and left venricular mass index(LVMI).2.Parameters of Left ventricular diastolic function: left atrial volume index(LAVI),mitral valve flow velocity ratio(E/A),septal and lateral mitral annular early-diastolic peak velocity(SeptE',LatE')and E/E'.3.Parameters of left atrium function:(1)Traditional ultrasonic parameters: left atrial total emptying fraction(LATotEF),left atrial passive emptying fraction(LAPassEF)and left atrial active emptying fraction(LAActEF).(2)2D-STE parameters: LA longitudinal strain during ventricular late diastole(LAa S),LA longitudinal strain during ventricular early diastole(LAe S)and LA longitudinal strain during ventricular systole(LAs S).4.Parameters of left atrial synchrony: Standard deviation for the time-to-peak(TP-SD)of regional strain was calculated during ventricular systole and late diastole,they were named as SDs and SDa,respectively.Results: 1.Comparison of left atrial function and synchrony between MS and control groups(1)LAD,LVEDD,IVST,LVPWT,RWT and LVMI were increased in the MS group compared with the Normal group(P<0.05),LVEF was no difference between MS and Normal groups(P>0.05).(2)E/A,SeptE' and LatE' were reduced and E/E',LAVImax,LAVImin and LAVIpreA were increased in the MS group compared with the Normal group(P<0.05).(3)LAs S and LAe S were reduced in the MS group compared with the Normal group(P<0.05),However,LAa S,LATotEF,LAPass EF and LAActEF were no significant difference between Normal and MS groups(P>0.05).(4)SDs was increased in the MS group compared with the controls(P<0.05),but SDa was no significant difference between the two groups(P>0.05).2.Comparison of left atrial function between the MS subgroup and the control group(1)LVEDD,RWT and LVMI were no difference between MS/DD-and Normal groups(P>0.05),but these parameters were increased in the MS/DD+ group compared with the Normal group(P<0.05).LAD,IVST and LVPWT were increased in the MS/DD-group and MS/DD+ group compared with the Normal group(P<0.05).The LVEF was no difference in the three groups(P>0.05).(2)There was no significant difference in diastolic function between group MS/DD-and group Normal(P>0.05).But,E/A,SeptE' and LatE' were reduced and E/E' was increased in the MS/DD+ group compared with the Normal group and MS/DD-group,LAVImax,LAVImin and LAVIpre A were increased only in the MS/DD+ group compared with the Normal group(P<0.05).(3)LAe S was reduced in the MS/DD-group compared with the Normal group.LAs S,LAe S,LATotEF and LAPassEF were reduced in the MS/DD+ group compared with the Normal group.Forthemore,the LAs S,LAe S and LATotEF were reduced in the MS/DD+ group compared with the MS/DD-group(P<0.05).However,there was no significant difference in the rest(P>0.05).Conclusions: 1.The LA conduit function has decreased when the left ventricular diastolic function is not significantly reduced of MS patients.When the left ventricular diastolic function is significantly reduced,the LA conduit function is further reduced.Forthemore,the LA reservoir function is also reduced.2.The synchrony of LA in the ventricular systole of MS patients was impaired.