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Fig. 5
Advanced 2D wall motion measurement by speckle-tracking analysis after cryoinjury reveals segmental and regional motion and deformation disturbances.
(A) Absolute radial displacement of individual segments at indicated time points. The ventricle was divided in six segments as indicated with segment 1 and 2 representing the anterior wall (AW), 3 and 4 the apex (Ap), and 5 and 6 the posterior wall (PW) for subsequent displacement analysis. Small numbers indicate number of animals measured. (B) Average of radial displacement at indicated time points. (C) High resolution speckle-tracking analysis of radial (upper row) and longitudinal (lower row) displacement. The top region displays displacement of the AW, the central region of the Ap and the lower region of the PW. Absolute values are color coded with high values in light red and low values in light blue as indicated. Time scale and color coding bar as indicated. The pink line at 4dpi depicts injured area (MI). (D) 3D reconstruction of regional displacement at indicated time points enables identification of akinesis of injured AW at 4dpi and residual wall motion deficiencies at 60dpi, respectively. The lower right image shows a schematic illustration of the 3D-reconstrations. The u-shaped pink lines indicate consecutive systoles; t and the arrow below indicate the time progress and MI the infarcted area, also indicated by the bold pink line. (E) Modified AFOG-staining (myocardium in red, connective tissue and fibrotic areas in blue) stained sections of a sham operated control heart and at 120 and 180dpi. AW is to the right, PW to the left. Boxed area of the cryo-injured region is shown in higher magnification in the lower left corner of its respective overview picture. At 120dpi residual fibrotic deposition (arrows) together with a thickening of the compact myocardial layer (*) can be detected. Residues of fibrosis are still detectable at 180dpi. Note that the thickening of the compact myocardial layer (*) extends over a great segment of the AW. Ap, apex; A, atrium, AVV, atrio-ventricular valve; AW, anterior wall; B, bulbus arteriosus; MI, myocardial injury; PW, posterior wall; V, ventricle; VBV, ventriculo-bulbar valve. Values are expressed as means ± SEM; *, p<0.05; **, p<0.01, unpaired student’s t-test and ANOVA with post hoc comparisons by Bonferroni’s multiple comparison test