Assessment Of Global And Regional Left Ventricular Systolic Function By Real Time Three Dimensional Echocardiography: Clinic Applications And In Vivo Study

Part 1. Assessment of global and regional normal left ventricular systolic function by real time three dimensional echocardiographyObjective: To explore the feasibility, accuracy and reproducibility of real-time three dimensional echocardiography(RT-3DE) combined with semi-automatic boundary detection method in evaluating global & regional volume parameters and systolic function of normal left ventricle(LV), and to explore the heterogeneity of regional normal left ventricle systolic function.Methods: Thirty-six normal volunteers were studied, and all the three-dimensional echocardiographic datasets were acquired by Philips iE33 medical system. Then a series of LV parameters, namely, global end diastolic volume (gEDV), regional end diastolic volume (rEDV), global end systolic volume (gESV), regional end systolic volume (rESV), global stroke volume (gSV) , regional stroke volume (rSV), global ejection fraction (gEF) and regional ejection fraction (rEF), were off-line measured by Research-Arena 4D LV-Analysis CAP2.5 software. In 20 volunteers, global LV volume parameters acquired from RT-3DE were compared with corresponding values measured by biplane Simpson's method using two-dimensional echocardiography(2DE). Then all the regional LV volume parameters in different LV segments were compared respectively.Results: Evaluation of global LV systolic function:①No statistical differences are found between RT-3DE and Simpson's method in gEDV, gESV, gSV and gEF calculations.②gEDV, gESV, gSV and gEF measured by RT-3DE strongly correlate with those measured by Simpson's method.③Using RT-3DE, gEDV, gESV, gSV and gEF measured by the first examinator strongly correlate with those values measured by the second examinator, and inter-observer variabilities of RT-3DE are small.Evaluation of regional LV systolic function:①Regional volume-time curves of normal LV are"U-shaped"and uniform. Corresponding phases of all curve peaks are end diastole, and phases of valleys are in the neighborhood of end systole. Regional EF-time curves of normal LV are inversely"U-shaped". The valleys are zero, with corresponding phases being end diastole. The phases of peaks are in the neighborhood of end systole.②rEDV, rESV and rSV decrease from basal segment to apical segment in every LV wall. All the basal segments and apical segments are statistical differences, while in most of walls, there are no statistical differences between middle segments and apical segments.③rEF arise from basal segment to apical segment in every LV wall, but less segments are statistically different.④Comparing along LV longitude, rEDV, rESV, rSV of basal-segment group are larger than those of mid-segment group and apical-segment group, howerer, there are no statistical differences between mid-segment group and apical-segment group. rEF of basal-segment group are smaller than those of other two groups, howerer, there are no statistical differences between mid-segment group and apical-segment group.⑤Comparing along LV circumference, rEDV, rESV, rSV of anterior, anteroseptal and lateral segment group are largest, those of posterior and septal segment group take 2nd place, and those of inferior segment group are smallest. rEF in anterior and anteoseptal segment group is smaller than that in lateral, posterior and inferior segment group.Conclusions The new method of RT-3DE combined with semi-automatic boundary detection method can conveniently, feasibly, accurately and high-repeatedly measure globe and regional normal LV systolic function. Regional systolic function of normal LV is heterogeneity, rEDV, rESV, rSV and rEF show statistical differences between LV middle, apical segment and basal segment, and between LV walls in circumferential sectors. Part 2. Assessment of global and regional left ventricular systolic function in patients with coronary artery disease by real time three dimensional echocardiographyObjective: To explore the feasibility, accuracy and reproducibility of real-time three dimensional echocardiography(RT-3DE) combined with semi-automatic boundary detection method in evaluating global & regional left ventricular(LV) volume parameters and systolic function in patients with coronary artery disease(CAD), and to explore the characteristic of systolic function in CAD together with functional improvement after revascularization. Methods: Forty-two patients with CAD and 36 normal volunteers were studied, and all the three-dimensional echocardiographic datasets were acquired by Philips iE33 medical system. Then a series of LV parameters, namely, global end diastolic volume (gEDV), regional end diastolic volume (rEDV), global end systolic volume (gESV), regional end systolic volume (rESV), global stroke volume (gSV) , regional stroke volume (rSV), global ejection fraction (gEF) and regional ejection fraction (rEF), were off-line measured by Research-Arena 4D LV-Analysis CAP2.5 software.①In 25 patients, global LV volume parameters acquired from RT-3DE were compared with corresponding values measured by biplane Simpson's method using two-dimensional echocardiography(2DE).②According to angiography findings, 42 patients were divided into 3 groups. Group A consists of 14 patients with isolated left anterior descending artery(LAD) stenosis, group B consists of 12 patients with left circumflex artery(LCX) stenosis, and group C consists of 16 patients with LAD stenosis and other main coronary artery stenosis (a percent area stenosis of≥75%). Global and regional LV volume parameters of group A, group B, group C and normal contrast group were compared.③In 20 patients undergone revascularization therapy, RT-3DE images were acquired 1~3 days preoperatively, 1 week postoperatively and 3 months postoperatively respectively, and analyzed to reveal changes of global and regional LV systolic function after revascularization.Results: Comparison of global LV systolic function values from RT-3DE and 2DE:①In CAD group, gEDV, gESV, gSV and gEF measured by RT-3DE strongly correlate with those measured by Simpson's method, but the correlation coefficients are lower than those in normal group.②In CAD group, no statistical differences are found between RT-3DE and Simpson's method in gEDV, gESV, gSV and gEF calculations.③In CAD group, using RT-3DE, gEDV, gESV, gSV and gEF measured by the first examinator are consistent with and strongly correlate with those values measured by the second examinator.④Comparing with normal group, inter-observer variability of RT-3DE and Simpson's method increase in CAD group, and inter-observer variability of Simpson's method increased markedly, which is much larger than that of RT-3DE.Evaluation of regional LV systolic function of CAD group:①gEDV and gESV in group A and C incearse than normal group, besides, gEDV and gESV in group C are larger than group A and B.②gSV in group C is smaller than normal group, and relationship of gEF in different groups is normal group>group B>group A>group C.③In CAD group, regional LV volume-time curves are disuniform. Curvatures of ischemic segments decrease, and coordinates of curve valleys are disperse. Regional LV EF-time curves show similar changes, becoming disuniform. Curvatures of ischemic segments decrease, and coordinates of curve peaks are disperse.④In group A, rEF in anteroseptal, anterior and apical segments are much lower than corresponding segments values in normal group. rEF in basal septal, mid septal and mid lateral segments are slightly lower than corresponding segments values in normal group. However, in most of above-mentioned segments, rEDV, rESV increase and rSV decrease.⑤In group B, rEF in posterior, inferior, septal segments and mid lateral segments are lower than corresponding segments values in normal group. In above-mentioned segments, rEDV show no evident change, while in most of the segments, rESV increase and/or rSV decrease.⑥In all segments of group C, rEF are lower than corresponding segments values in normal group, moreover rESV and rEDV increase.⑦ In group A and B, rEF of ischemic segments is much lower than that of normal segments, and there is statistical difference between them.Comparison of LV systolic function before and afte revascularization:①Comparing with pre-operation, 1 week after revascularization, gEDV, gESV, gSV and gEF show unobvious change, but rEF of basal anterior and basal anteroseptal segments increase.②Comparing with pre-operation, 3 months after revascularization, gEDV, gESV, gSV show unobvious change, but gEF increases. rEF of basal anterior and basal anteroseptal segments much more increase, and rEF of other segments become increased.Conclusions The new assessment method of RT-3DE combined with semi-automatic boundary detection method can conveniently, feasibly, accurately and high-repeatedly measure globe and regional LV systolic function of patients with CAD, and it can be used in follow-up study of revascularization therapy. Global and regional LV systolic function of patients with CAD decrease, and the decrease is affected by number of stenostic coronary artery and revascularization therapy. Part 3. Assessment of global and regional left ventricular systolic function in acute myocardial infarction canine by real time three dimensional echocardiographyObjective: To explore the feasibility and accuracy of real-time three dimensional echocardiography(RT-3DE) combined with semi-automatic boundary detection method measure global and regional left ventricular(LV) volume parameters and systolic function in acute myocardial infarction(AMI) canine, and to explore the effect of coronary artery ligation site on global and regional LV systolic function.Methods: Twenty canines were successfully undergone coronary artery ligation and suffered from AMI. According to coronary artery ligation site, all the canines were divided into 2 groups: left anterior descending artery(LAD) ligation group(11 canines)and left circumflex artery(LCX) ligation group(9 canines). They were taken RT-3DE examination before ligation, 10 minutes, 1 hour and 3 hour after ligation. Then a series of LV parameters, namely, global end diastolic volume (gEDV), regional end diastolic volume (rEDV), global end systolic volume (gESV), regional end systolic volume (rESV), global stroke volume (gSV) , regional stroke volume (rSV), global ejection fraction (gEF) and regional ejection fraction (rEF), were off-line measured by Research-Arena 4D LV-Analysis CAP2.5 software.Results: Changes of LV global systolic function in AMI canine:①In LAD ligation group, 10min and 1h after ligation, gESV and gEDV increase respectively, and the increase last into 3h post-ligation.②In LAD ligation group, 10min after ligation, gEF decrease and last into 1h post-ligation. Three hours after ligation, gEF slightly improve but without statistical significance.③In LCX ligation group, 10min after ligation, gESV increase and last into 3h post-ligation. One hour after ligation, gEDV increase and slightly recover 3h after ligation.④In LCX ligation group, 10min after ligation, gEF decrease and last into 1h post-ligation. Three hours after ligation, gEF improve and with statistical significance.⑤ Ten minutes, 1 hour and 3 hour after ligation, gEF of LAD ligation group are all lower than rEF of LCX ligation group.Changes of LV regional systolic function in AMI canine:①In baseline, regional volume-time curves of canine LV are"U-shaped"and uniform. Corresponding phases of curve peaks are all end diastole, and phases of valleys are in the neighborhood of end systole. Regional EF-time curves of baseline canine are inversely"U-shaped". The valleys are zero, with corresponding phases being end diastole. The phases of peaks are in the neighborhood of end systole.②After coronary artery ligation, regional LV volume-time curves become disuniform. Curvatures of ischemic segments decrease, curve valleys of ischemic segments are shallow, and coordinates of valleys are disperse. Regional LV EF-time curves show similar changes, becoming disuniform. Curvatures of ischemic segments decrease, curve peak of ischemic segments fall, and coordinates of peaks are disperse.③LAD ligation primarily affect LV anterior, anteroseptal and apical segments.Ten minutes after ligation, rEF of anterior, anteroseptal and apical segments decrease. One hour after ligation, rEF of above segment decrease partly, and rEF of basal lateral, mid lateral and mid septal segments decrease too. Three hours after ligation, rEF in minority of abnormal segments slightly recover.④LCX ligation primarily affect LV basal, inferior and posterior segments. Ten minutes after ligation, rEF of basal segments, mid inferior segment and mid posterior segment decrease. One hour after ligation, rEF of above segment decrease partly, and rEF of mid septal and apical inferior segments decrease too. Three hours after ligation, rEF in minority of abnormal segments slightly recover.Conclusions The new assessment method of RT-3DE combined with semi-automatic boundary detection method can conveniently and accurately measure globe and regional LV systolic function of AMI canine. LAD ligation and LCX ligation affect canine LV global and regional systolic function differently.