3-DIMENSIONAL ECHOCARDIOGRAPHY COMPARED TO 2-DIMENSIONAL ECHOCARDIOGRAPHY FOR MEASUREMENT OF LEFT-VENTRICULAR MASS ANATOMIC VALIDATION IN AN OPEN-CHEST CANINE MODEL

A three-dimensional echocardiographic system has been developed that c an accurately compute left ventricular mass in vitro. This study was d esigned to validate the new echocardiographic system for the measureme nt of left ventricular mass in vivo and to compare the accuracy of thr ee-dimensional echocardiography to the accuracy of conventional two-di mensional echocardiography for measuring left ventricular mass, Echoca rdiographic imaging was performed 6 h following coronary ligation in 2 0 open chest dogs, at which time the heart was excised and the left ve ntricle weighed. Three-dimensional echocardiography used multiple shor t axis sections and polyhedral surface reconstruction to compute myoca rdial volume. The two dimensional methods employed the truncated ellip soid model and the area-length model. Myocardial volume was multiplied by 1.05 g/cc and echocardiographic mass estimates were compared to th e true left ventricular weight. Three-dimensional echocardiography pro vided the best correlation (r = 0.96, v r = 0.88 and r = 0.83 for the truncated-ellipsoid and area-length methods, respectively), and the lo west standard error of the estimate for the regression equation (+/- 5 .5 g v +/- 11.0 g and +/- 14.6 g, respectively). Three dimensional ech ocardiography also had the lowest standard deviation for the echo-true mass differences (+/- 5.8 g v +/- 10.7 g and +/- 14.2 g) and a lower root mean square percent error (6.8% v 12.6% and 12.7%). In this open chest canine model, three-dimensional echocardiography is more accurat e than standard two-dimensional echocardiographic methods for measurin g left ventricular mass.