Figure 4

Bull's eye views of all subjects in the study. The colour legends are reproduced, with yellow to red being shortening, blue being lengthening, and deeper colour means greater magnitude of either shortening or lengthening. The same colour legend is used for strain rate and strain, but the scales differ somewhat, resulting deeper colour in the strain images. The two upper rows are the normal subjects, mid systolic strain rate and end systolic strain. In control subjects 2 and 5 a small defect top left is seen, which is the aortic root. Large reverberations are seen in strain rate and strain in subject 4 and 6, and in strain in subject 3 as well. Reverberations are seen as circular bands at the midwall level, being due to the spatial interpolation process. In addition, basal artefacts are seen in subject 1, 5 and 6. Subject 6 shows areas of light colours due to dropouts as well. The three bottom rows are the infarction patients. Patients 2 and 4 had inferior, the rest apical infarctions. The infarcts have a more typical location, but the infarct in patient 4 may be difficult to separate from the basal artefacts in control subjects. In patient 5, there are reverberation artefacts as well, seen in the lateral base. The diagnosis of infarction was as easy with mid systolic strain rate as with end systolic strain, as is apparent in this figure. However, by adding post systolic shortening, the diagnosis of infarction was facilitated. Post systolic shortening was present in all six patients in this acute phase, and is seen to extend beyond the area of hypo- and dyskinesia in all. In the early diastolic images, there is visible inhomogeneity that is a normal phenomenon, not the results of pathology or reverberations. In some subjects small areas of inverted colour in the apex due to angular distortion can be seen, however, this area is small, and in most images it has been blanked.