Contrast echocardiography in @entity741 . III. An in vivo comparison of the extent of abnormal wall motion with the area at risk for XXXX .

@entity39 @entity235 @entity63 @entity1563 @entity910 @entity741 @entity432
To define the in vivo relation between abnormal wall motion and the area at risk for @entity39 after acute coronary occlusion, 11 open chest @entity235 were studied. Five @entity235 underwent left anterior descending @entity1563 and six underwent left circumflex @entity432 . Area at risk was defined at five short-axis levels (mitral valve, chordal, high and low papillary muscle and apex) using myocardial contrast echocardiography. Wall motion was measured in the cycles preceding injection of contrast medium. Two observers used two different methods to measure wall motion. In method A, end-diastolic to end-systolic fractional radial change for each of 32 endocardial targets was determined. The extent of abnormal wall motion was then calculated using three definitions of wall motion abnormality: @entity910 / @entity910 , fractional inward endocardial excursion of less than 10%, and fractional inward endocardial excursion of less than 20%. In method B, the information from the entire systolic contraction sequence was analyzed and correlated with a normal contraction pattern. The best linear correlation between area at risk (AR) and abnormal wall motion (AWM) was achieved using method B and expressed by the following linear regression: AWM = 0.92 AR + 3.0 (r = 0.92, p less than 0.0001, SEE = 1.7%). Of the three definitions of abnormality used in method A, the best correlation was achieved between area at risk and less than 10% inward endocardial excursion and was expressed by the following polynomial regression: AWM = -0.01 AR2 + 1.5 AR -0.14 (r = 0.92, p less than 0.001, SEE = 1.7%). These data demonstrate that there is a definite relation between area at risk and abnormal wall motion but that this relation varies depending on the method used to analyze wall motion. However, wall motion during acute @entity63 is also influenced by the loading conditions of the heart. Because these may vary in a manner that is independent of the ischemic process, measurement of both risk area and abnormal motion may provide a more comprehensive assessment of cardiac function in @entity741 than is provided by the measurement of either alone.
