Final Feigenbaum’s Echocardiography DIGITAL

Feigenbaum’s Echocardiography

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Feigenbaum’s Echocardiography

FIGURE 5.16. Parametric imaging derived from a patient with nor- mal left ventricular systolic function. The bull's-eye plots depict timing of contraction (upper plot) and wall excursion (lower plot). Individual volumetric changes for each of the 17 segments are plot- ted in the lower graph. Detailed parameters of temporal heterogene- ity are displayed on the right.

Strain and Strain Rate Imaging (Deformation Imaging)

short-axis views (Figs. 5.18 and 5.19). While it is feasible to extract multiple two-dimensional views from the three-dimensional data- set, the image quality of the extracted views is below that obtained from a dedicated two-dimensional scan. is is demonstrated in Figure 5.18 which illustrates a three-dimensional dataset from which an apical four-chamber view has been extracted at the lower le. At the lower right is a superimposed two-dimensional apical four-chamber view from the same patient recorded on the same platform but utilizing dedicated two-dimensional scanning.

e majority of analysis techniques discussed thus far analyze le ventricular wall motion from the frame of reference of the transducer. As such, rotation, translational motion, and tethering confound analysis. Doppler tissue imaging and speckle tracking allow for evaluation of a myocardial region with reference to an adjacent myocardial segment rather than to a „xed transducer posi- tion and theoretically provide more accurate data regarding ventric- ular function. Analysis of ventricular mechanics or shape during

FIGURE 5.18. Comparison of the three-dimensionally and two-dimensionally derived apical four-chamber views in a patient with high image quality. The upper figure is the three- dimensional dataset from which apical four- and two-chamber views have been extracted. At the lower left is the three-dimensionally derived apical four-chamber view. At the lower right is a dedicated two-dimensional scan from the same patient which has been superimposed in the location where the two-chamber view was originally displayed. Note the substantially better resolution available from the dedicated two-dimensional probe compared to the extracted four-chamber view from the three-dimensional probe.

FIGURE 5.17. Transthoracic three-dimensional acquisition in a patient with an ischemic cardiomyopathy. The two upper panels are fitted models to the automatically determined endocardial border from the three-dimensional dataset. An apical view as well as a short- axis composite as viewed from the apex are presented. The individual graphs of volume over time in each of the 16 segments demonstrate regional variation in left ventricular function. The table at the right outlines a variety of automatically determined measures including an ejection fraction of approximately 35% as well as parameters of heterogeneity of contraction.

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