Left Atrial Volume Tracking Technique And Tissue Doppler Imaging In Assessment Of Left Atrial Volume,Function And Synchrony In Patients With Coronary Artery Stenosis

BackgroundCoronary artery stenosis(CAS)causes myocardial ischemia,resulting in left atrial volume,function and synchronization changes.There are more reports of the effects of generalized coronary artery disease on the left atrial,but the effect of single CAS on left atrial volume,function and synchronization was rarely studied.In this study,left atrial volume tracking(LAVT)technique and tissue doppler imaging(TDI)were used to evaluate comprehensively the changes of left atrium volume,function and synchronization in patients with different coronary artery stenosis.Chapter 1 Left atrial volume tracking technique in assessment of left atrial volume and function changes in patients with different coronary artery stenosisObjectives To explore the clinical value of left atrial volume tracking(LAVT)technique in evaluation of left atrial volume and function changes in patients with different coronary artery stenosis(CAS).Methods Thirty-nine patients with coronary artery stenosis(CAS)patients who were checked by coronary angiography(CAG)and confirmed single CAS rate>75%were collected.There were twenty-two stenosis patients(LAD group)with left anterior descending coronary artery and seventeen stenosis patients(LCX group)with left coronary artery circumflex.Thirty patients(control group)with coronary artery stenosis rate<30%were collected.Four-chamber and two-chamber of apical dynamic two-dimensional images of all patients were obtained.LAVT technique was used to obtain left atrial volume-time curve line and volume change rate-time curve line.Maximal volume(LAVmax),pre-systolic volume(LAVp),minimal volume(LAVmin)of left atrial,and peak filling rate in systolic(dv/dt-S),peak passive emptying rate in early diastolic(dv/dt-E),peak active emptying rate in late diastolic(dv/dt-A)of left atrial were measured.LAVimax,LAVip and LAVimin were obtained by calibrating the volume parameter by body surface area(BSA).After total emptying rate(LAtE%),passive emptying rate(LApE%)and active emptying rate(LAaE%)of left atrial were calculated.Results There were statistically significant differences in LAVimax,LAVip and LAVimin among three groups(all P<0.05).LAVimax,LAVip and LAVimin in the LAD group and LCX group were larger than those in the control group(all P<0.05).LAVimax,LAVip,LAVimin in the LAD group were smaller than those in the LCX group(all P<0.05).There were statistically statistical differences in LAtE%,dv/dt-S,LApE%,dv/dt-E and LAaE%,dv/dt-A among three groups(all P<0.05).LAtE%,dv/dt-S and LApE%,dv/dt-E in the LAD group and LCX group were lower than those in the control group(all P<0.05).LAtE%,dv/dt-S and LApE%,dv/dt-E in the LAD group were larger than those in the LCX group(all P<0.05).LAaE%,dv/dt-A in the LAD group were higher than those in the LCX group and control group(all P<0.05).LAaE%,dv/dt-A in the control group were larger than those in the LCX group(all P<0.05).Conclusions1.Left atrial volume and function changes in patients with single coronary artery stenosis(stenosis rate>75%).2.There were differences in the effects of different coronary artery stenosis on the left artery.Compared in patients with LAD stenosis,changes of left atrial volume and functional in patients with LCX stenosis are more significant.3.LAVT enables noninvasive measurement of left atrial volume and rate of change in multiple phases of continuous cardiac cycle,providing valuable and detailed reference for clinical assessment of left atrial volume and function in patients with different coronary artery stenosis.Chapter 2 Evaluation of intracardiac and atrial synchrony in patients with different coronary artery stenosis by tissue Doppler imagingObjectives Atrial contraction time,atrial electrical-mechanical coupling time,atrial electrical-mechanical delay time were measured by tissue doppler imaging(TDI)to investigate the changes of the atrial-intral and atrial-inter synchronization in patients with different coronary artery stenosis.Methods Thirty-nine patients with coronary artery stenosis(CAS rate>75%)were collected.There were twenty-two stenosis patients(LAD group)with left anterior descending coronary artery and seventeen stenosis patients(LCX group)with left coronary artery circumflex.Thirty patients(control group)with coronary artery stenosis rate<30%were collected.Under tissue doppler image(TDI)conditions,the sample volume was placed at the left atrial lateral wall at mitral annulus,interatrial septum and right atrial lateral wall at tricuspid annulus in apical four-chamber view,and get various parts TDI spectrum.Then atrial contraction time(A)was measured from the durative time of the A wave on the TDI spectrum on the three parts.Atrial electrical-mechanical coupling time(P-A)was measured form the initiation of the P wave on the electrocardiogram(ECG)to the A wave starting point on the TDI spectrum on the three parts.After left,right atrial-intral and atrial-inter electrical-mechanical delay time(T-LA,T-RA,T-LR)were calculated.Results There were no statistically significant differences in RAD1,RAD2 among three groups(all P>0.05).There were statistically significant differences in LAD1,LAD2,LAD3 among three groups(all P<0.05).LAD1,LAD2,LAD3 in the LCX group were larger than those in LAD group and control group(all P<0.05).LAD1,LAD2,LAD3 in the LAD group were larger than those in the control group(all P<0.05).There were no statistically significant differences in AIAS,ARA,P-AIAS,P-ARA,T-RA among three groups(all P>0.05).There were statistically significant differences in ALA,P-ALA,T-LA,T-LR among three groups(all P<0.05).ALA,P-ALA,T-LA,T-LR in the LCX group were higher than those in the LAD group and control group(all P<0.05).ALA,P-ALA,T-LA,T-LR in the LAD group were larger than those in control group(all P<0.05).Conclusions1.Atrial synchronization changes in patients with single coronary artery stenosis(stenosis rate>75%).2.There was a significant difference in left atrial synchronization between different coronary artery disease stenosis,and the change of LCX stenosis in left atrial synchronization was more significant than that of LAD stenosis.3.TDI can accurately analyze atrial electrical-mechanical changes,so as to evaluate the atrial-intral and atrial-inter synchronization in patients with different coronary artery stenosis,for the study of atrial synchronization provides a quantitative basis for evaluation.