QUANTIFICATION OF LEFT-VENTRICULAR DIMENSIONS ON LINE WITH BIPLANE TRANSESOPHAGEAL ECHOCARDIOGRAPHY AND LATERAL GAIN COMPENSATION

To determine the feasibility and accuracy of biplane transesophageal e chocardiography (TEE) with automatic boundary detection (ABD) for the estimation of left ventricular areas, we examined 19 consecutive patie nts with the use of this technique. In addition, we evaluated the util ity of lateral gain compensation (LGC) to improve the online tracking of the ABD algorithm on the lateral endocardial-blood boundary of the echocardiographic image. The transverse plane short-axis TEE view and the longitudinal plane two chamber TEE view were used for the analysis . A semiquantitative estimate (in degrees) of the endocardial circumfe rence, in which the boundary was correctly identified and tracked on l ine, improved from a mean of 198-degrees to 360-degrees with LGC (P < 0.001). Results of comparisons of offline and online biplane TEE cavit y areas revealed excellent correlations of values for the 16 patients (84%) in whom adequate transverse plane short-axis images were obtaine d (r values > 0.9 at systole and diastole). The correlation was also e xcellent (r values > 0.9) in the nine patients in whom longitudinal pl ane two-chamber views adequate for ABD analysis were obtained at systo le and diastole. LGC significantly improved the accuracy of endocardia l detection and tracking, which otherwise would be limited due to the anisotropic properties of the myocardium. Thus, ABD during biplane TEE may be feasible in a significant number of patients and accurately re flects left ventricular areas when compared with offline methods.