Two-dimensional Echocardiographic Automatic Boundary Detection for Evaluation of Left Ventricular Function in Unselected Adult Patients

Recent modications in two-dimensional echocardiography imaging include automatic boundary detection (ABD) that permits instantaneous quantification of left ventricular (LV) function. To define its clinical application from different views in consecutive patients (n = 68), we performed both conventional two-dimensional imaging and ABD with lateral gain compensation and compared the ability of each method for visualization of myocardial segments. From each view (short-axis and apical four- and two-chamber), the LV was divided into six wall segments. The short-axis view was obtained successfully in 53 of 68 patients; of the possible 318 segments, 96% were visualized adequately by two-dimensional echocardiography and 89% by ABD. From the four-chamber view, obtained in 63 of 68 patients, visualization of 378 possible segments was 93% by two-dimensional imaging and 86% by ABD, respectively. From the two-chamber view obtained in 58 of 68 patients, the success rate was 88% and 80% (two-dimensional imaging and ABD, respectively). ABD detected LV endocardial/blood borders in all six segments of each view in 73%, 72%, and 72% of cases, concordant with adequate two-dimensional imaging. Discrepancies between two-dimensional imaging and ABD were usually in the short-axis inferior and lateral, four-chamber lateral, and two-chamber anterior segments. There were 46 patients with normal LV wall motion and 22 with wall-motion abnormalities. The average time required to perform ABD was 375 seconds (range 180 to 780 seconds). Thus ABD is clinically applicable, has similar yield in parasternal and apical views, does not add excessive time for analysis, and provides comparable visualization of LV segments if acceptable conventional two-dimensional images are obtained.