Study Of Real-time Three-dimensional Echocardiography For Quantifying Left Ventricular Global And Regional Mass And Function In Canine Acute Myocardial Infarction

Objective (1)To investigate the feasibility and accuracy of RT3DE for analysis of left ventricular global and regional volume,ejection fraction and mass;(2)To investigate the feasibility and accuracy of RT3DE for analysis of left ventricular global and regional function ; (3)to validate the accuracy of different method of three-dimensional echocardiography for measurement of left ventricular function;(4) To investigate the feasibility of ME,2DE and RT3DE for quantifying left ventricular global and regional mass and function in canine acute myocardial infarction.Methods Coronary ligation was performed in 18 open chest dogs .M-mode,two-and real-time three-dimensional echocardiographies were performed to measure LVEDV 4 hours after coronary occlusion, and the results were compared each other. Three-dimensional echocardiography was also performed to measure left ventricular mass 4 hours after coronary occlusion, and the results were compared with those of anatomic method. Three-dimensional echocardiography was performed to measure left ventricular regional ejection fraction (LVEFr) before and after coronary occlusion (at first it was performed, later 4 hours).Results There were no statistically significant differences between RT3DE,2DE and ME for measurement of EDV,ESV and LVEF before coronary occlusion (P>0.05),but there were statistically significant differences between RT3DE and 2DE(or ME) after coronary occlusion(P<0.05).Regression analysis demonstrated high correlation between left ventricular mass measured by RT3DE and anatomic method,inclu- ding left ventricular global mass and segmental mass of mitral valve,papillary muscles and Apex of heart (r=0.93,SEE=3.01g;r=0.91, SEE=1.01g;r=0.93,SEE=1.79g;r=0.92, SEE=1.62g P>0.05). The left ventricular global mass and segmental mass of papillary muscles and apex of heart had grown after coronary occlusion (P<0.05),but segmental mass of mitral valve had not grown(P>0.05).The most regional end-diastolic and end-systolic volume of seg- ments after coronary occlusion were significantly larger than those before coronary occlusion (P<0.05). The regional stroke volume of some segments(basal anteroseptal wall,medium anteroseptal wall,apical septal wal1 and apical wall),regional ejection fraction of all segm- ents and regional to global EF ratioes (EFRGs) of all segments after coronary occlusion were significantly lower than those before coronary occlusion (P>0.05). The regional to global SV of some segments(medium anteroseptal wall,apical septal wal1 and apical wall)were significantly lower than those those before coronary occlusion (P>0.05),but some segments(basal lateral wall, basal posterior wall ,basal inferior wall and basal interventricular sep- tum wall)were significantly larger than those before coronary occlusion.Conclusions For geometrically asymmetric left ventricular volumes associated with acute myocardial infarction, real-time three-dimensional echocardiography can accurately measure left ventricular global and regional volume,ejection fraction and mass. It is a breakthrough for real-time three-dimensional echocardiography to assess left ventricular regional function by measureing left ventricular regional mass.Real-time three-dimensional echocardiography can assess left ventricular remoding after acute myocardial infarction by measureing left ventricular global and regional volume,ejection fraction and mass .