DK2985_C000 1..28 - AlSharqia Echo Club

94 Transesophageal EchocardiographyFigure 5.5 Importance of spatial orientation in the measurement of the diameter of the left ventricle (LV). The measurements obtainedon (B) will overestimate ventricular diameters because they were obtained in an oblique plane (LA, left atrium).edge of the posterior wall of the aorta to the leading edgeof the posterior wall of the LA. The normal value is3.8 + 0.98 cm for the LA (7).Measurements of the Left VentricleFrom a short-axis 2D view of the LV just beneath themitral valve leaflets, the M-mode cursor is positionedthrough the center of the left ventricular cavity. Enddiastolicmeasurements are first made at the onset of theQRS complex on the ECG (Fig. 5.6).The interventricular septal thickness (IVST) ismeasured from the leading edge of the interventricularseptum to the leading edge of the endocardial border ofthe interventricular septal wall.The left ventricular end-diastolic dimension (LVEDD)is measured from the leading edge of the endocardialborder of the interventricular septal wall to the leadingedge of the endocardial border of the posterior wall.The posterior wall thickness (PWT) is measured fromthe leading edge of the endocardial border of the posteriorwall to the leading edge of the epicardial surface of theposterior wall.End-systolic measurements are performed at the peakposterior displacement of the ventricular septum.The left ventricular end-systolic dimension (LVESD) ismeasured from the leading edge of the endocardial borderof the interventricular septal wall to the leading edge of theendocardial border of the posterior wall.Measurements of the Right VentricleFrom the same view used earlier for the left ventriculardimension, the right ventricular end-diastolic dimension(RVEDD) is measured from the leading edge of the endocardialborder of the right ventricular anterior wall to theleading edge of the right endocardial border of the interventricularseptum.Note that the normal values usually reported for thesemeasurements are obtained by transthoracic M-modeechocardiography.2. Two-Dimensional MeasurementsWhen the cardiac structures of interest cannot be positionedso that they are perpendicular to the line ofM-mode interrogation, 2D echocardiographic measurementsare preferred. It is of note that the ASE recommendedmethod for measuring cardiac structures by 2Dechocardiography differs as it is done from inner edge toinner edge (as opposed to the leading edge to leadingedge method in M-mode echocardiography) (8). Normalvalues have been reported for transesophageal echocardiography(TEE) (9,10) (Fig. 5.7).