Table 1 Comparison of recommended steps for tissue Doppler and speckle tracking based deformation imaging
From: Tissue Doppler, Strain and Strain Rate in ischemic heart disease “How I do it”
Tissue Doppler | Speckle tracking | |
|---|---|---|
Image acquisition | - TDI images with insonation angle <15° (single wall acquisition if needed) and adequate velocity scale (to avoid aliasing) | - Optimized 2D images avoiding foreshortening and stationery artefacts (reverberation) |
-Frame rate > 100 fps (ideally > 140 fps) | - Frame rate: 40–80 fps | |
- Acquire spectral Doppler traces of mitral and aortic valve for timing | - Acquire a spectral Doppler trace at least of the aortic valve as backup for timing | |
Image analysis | - Measure aortic and mitral valve opening and closure in order to define cardiac phases | |
-Order of image analysis: arbitrary | - Start analysis with the apical long axis view in order to define aortic valve closure. Use Doppler derived data if needed. | |
- Set the region of interest (ROI) shape and size oval somewhat smaller than the wall thickness. Position the needed number of ROIs it in the middle of the segments to be analysed. Track ROI position if needed. | - Contour the myocardium according to the procedure proposed by the vendor. Avoid including the bright pericardium. | |
- Evaluation of curve quality. Repositioning of the ROI if needed. | - Careful visual control of the proposed tracking. Repositioning of the contours if needed. Exclusion of suboptimally tracked segments if re-contouring is unsuccessful. | |
- Shape analysis of the curves | - Shape analysis of the curves | |
- Measurement of peak values and further post-processing if needed | - Measurement of peak values and further post-processing if needed |