Automated tissue Doppler imaging for identification of occluded coronary artery in patients with suspected non-ST-elevation myocardial infarction

Figures

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  Fig. 1. Flow diagram of the study population. TDI = tissue Doppler imaging. STE-AFI = speckle tracking echocardiography Automated Functional Imaging

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  Fig. 2. The process from EchoPac to values in the TDI-software. 2a: 3 apical views from EchoPac. 2b: Velocities and position values are extracted by the automated method into a 3D mesh, assuming 60 degrees between imaging planes and a bullseye plot. The colors reflect the strain rate values from red (-3.0 s− 1 /contraction) to yellow (0 s− 1) to dark blue (3.0 s− 1/stretch). Red subsegments show values that are discarded. 2c: Extracted peak values (indicated by red cross) from segmental curves. i: peak systolic strain. ii: peak systolic strain rate. iii: peak post systolic strain. X-axis is frame-numbers, Y-axis is strain (%) for curve i and ii and strain rate(s− 1) for iii. The periods in the heart cycle where the peak-values are searched for are marked in green. Red vertical line marks the aorta valve closure defined as the smallest reconstructed volume from the 3D mesh. ES: End Systole. AAVC: After Aorta Valve Closure

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  Fig. 3. 16-segment model adapted from American Heart Association (AHA) [12]. Values from segment 1, 2, 7, 8, 13 and 14 were averaged to Left Anterior Descending artery (LAD) territory, segment 5, 6, 11, 12 and 16 to Circumflex artery (CX) territory and segment 3, 4, 9, 10 and 15 to the Right Coronary Artery (RCA) territory

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  Fig. 4. ROC analysis for identification of acute coronary occlusion by global deformation measurements by TDI and STE-AFI AUC [95% Confidence Interval] for the deformation measurements. PSI = Post systolic index

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  Fig. 5. Illustration of effect of reverberations on strain rate curves. The yellow curve is from outside the reverberation whilst the green curve is from inside the reverberation. The size of the region of interest (ROI) is the same. The curve is inverted in the area of the reverberation