| Objective This study was designed (1) to compare the accuracy ofthree-and two-dimensional echocardiography for quantifying left ventricular end-diastolic volumes (LVEDV); (2) to test the reproducibility of three-dimensional echocardiography for measurement of LVEDV; (3) to validate the accuracy of three-dimensional echocardiography for measurement of left ventricular mass (LVM); (4) to evaluate the quantitative assessment and its significance of left ventricular regional function before and after myocardial infarction (5 )to explore how well change of LVEFr quantified by three-dimensional echocardiography reflects the actual anatomic infarct mass.Methods Coronary ligation was performed in 11 open chest dogs. Two-and three-dimensional echocardiographies were performed to measure LVEDV 4 hours after coronary occlusion, and the results were compared with those of fluid method. The three-dimensional echocardiographic date set was processed, and quantitative dates were derived weeks apart for evaluatingintraobserver variability. Another investigator analyzed the date for obtaining interobserver variability. 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 during the period of 4 hours after coronary occlusion (at first it was performed every 15 minutes, later every 30 minutes). With triphenyltetrazolium chloride staining, anatomic infarct regions were delineated, dissected, and weighed.Results Three-dimensional echocardiographic measurements of LVEDV correlated more closely with LVV of fluid method(r=0.98,SEE 1.69ml)than did the two-dimensional Simpson's method(r=0.87,SEE 4.62ml) . Analysis of intra- and interobserver variability showed strong indexes of agreement in the measurement of LVEDV with three-dimensional echocardiography. Regression analysis demonstrated high correlation between left ventricular mass measured by three-dimensional echocardiography and the actual weight measured by anatomic method(r=0.97, SEE 3.74g). The anatomic infarct mass was 9.8 3.1g(mean SD);The percentage of left ventricle involved in infarction was 18.7% 4.7%. One-way ANOVA analysis demonstrated significant reduction of LVEFr in middle anterosepter and apical wall. The correlation between percent of left ventricle involved in infarction (x) and themean change of LVEFr in middle anterosepter and apical wall 4 hours after coronary occlusion (y)was y=1.61x+15.62,r=0.88,P<0.01.Conclusions For geometrically asymmetric left ventricular volumes associated with acute myocardial infarction, volume-rendered three-dimensional echocardiography can quantitatively measure left ventricular volume, left ventricular mass, and left ventricular regional ejection fraction.
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