Influence of echocardiographic scan plane location and number on the accuracy of three-dimensional left ventricular volume and shape determination

Quantitative 3-dimensional (3-D) echocardiography provides accurate assessm ent of left ventricular (LV) volume, shape, and function, but depends on ma nual endocardial border tracing. This study determined the minimal number o f borders that need to be traced to obtain an accurate analysis of not only the volume of the left ventricle but also its shape, using the integrated methods for quantitative 3-D echocardiography developed by our laboratory. Transthoracic 3-D echocardiographic studies were obtained in 9 normal subje cts and 6 patients with heart disease by freehand scanning. The LV endocard ium was manually traced in 17 +/- 5 imaging planes and reconstructed in 3 d imensions. The volume and shape of each reconstruction were compared with v alues measured from surfaces reconstructed from 8 subsets containing 2 to 7 borders; each subset was acquired from different combinations of spatially distributed parasternal and apical views. Accurate measurements were obtai ned from data sets having greater than or equal to 5 borders, regardless of whether the image planes were predominantly apical or parasternal views. I n conclusion, the LV border should be traced in greater than or equal to 5 imaging planes to obtain accurate measurements of volume and shape, The pie cewise smooth reconstruction method and freehand scanning using a magnetic field tracing system allow the borders to be acquired from whatever combina tion of acoustic windows and views provides optimal image quality. (C) 1999 by Excerpta Medica, Inc.