1. TISSUE DOPPLER BASICS
DR BIJILESH U

2. Tissue Doppler imaging (TDI) is a relatively new echocardiographic technique that uses Doppler principles to measure the velocity of myocardial motion.
In conventional doppler we record the motion of blood…By adjusting gain and reject settings, the Doppler technique can be used to record the motion of the myocardium rather than the blood within it

3. Assessment of myocardial motion
2D imaging
Poor delineation of endocardial borders
Inter observer variability
Qualitative than quantitative
Poor regional function assessment
Diastolic function assessment limited
All tehse are better with tdi , inter observer variability less as tdi is a aemi quantitive method. Better borders due to spatialresolution, regional function assessment better, stand alone tecniqe in diastolic fn

4. TDI TVI obtain data even in suboptimal 2D windows
Less inter observer variation
Quantitative than qualitative
Important in diastolic function assessment
Better regional assessment

5. Principles of TDI Doppler Effect
Frequency of a reflected ultrasound wave is altered by movement of the reflecting surface away from or towards the source

6. Doppler tissue Vs blood pool imaging
returning signal contains a broad range of frequency shifts with low-frequency shifts being related to slowly moving targets and high-frequency shifts to more rapidly moving targets. There is also a broad range in the signal amplitude with low-amplitude targets being represented by red blood cells and high-amplitude targets by tissue.

7. RBC s - relatively weak reflectors and fast moving
Conventional doppler -filters adjusted to exclude highly reflective objects and to maximize less reflective & high velocity objects

8. blood motion imaging, low shifts and high-amplitude targets are filtered out, and a spectral display representing blood pool motion is presented. Opposite filtering of low-amplitude and high-frequency shifts results in selective registration of tissue motion.

9. TDI- target is tissue rather than red blood cells.
Tissue has a greater reflectivity and slower motion,
Filters set to exclude high velocities and low-intensity reflectors.
Filters are set to parameters opposite
With this technique, either the myocardium targeted and weaker reflections from the higher velocity blood cells relatively excluded.

10. blood motion imaging, low shifts and high-amplitude targets are filtered out, and a spectral display representing blood pool motion is presented. Opposite filtering of low-amplitude and high-frequency shifts results in selective registration of tissue motion.

11. blood motion imaging, low shifts and high-amplitude targets are filtered out, and a spectral display representing blood pool motion is presented. Opposite filtering of low-amplitude and high-frequency shifts results in selective registration of tissue motion.

13. Limitations
TDI measures only the vector of motion that is parallel to the direction of the ultrasound
Incident angle between the beam and the direction of target motion varies from region to region
Limits the ability to provide absolute velocity
Unable to discriminate passive motion from active motion
One obvious limitation is that the incident angle between the beam and the direction of target motion varies from region to region. This limits the ability of the technique to provide absolute velocity

14. Tissue Doppler –imaging modes
Pulse wave Doppler
Color 2D imaging
Color M- Mode

15. Pulsed-wave TDI Used to measure peak myocardial velocities
Suited to the measurement of long-axis ventricular motion
Longitudinally oriented endocardial
fibers are most parallel to the ultrasound beam in the apical views.
TDI can be performed in pulsedwave and color modes.

16. mitral annular motion :good surrogate measure of overall longitudinal left ventricular (LV) contraction and relaxation
To measure longitudinal myocardial velocities, the sample volume is placed in the ventricular myocardium immediately adjacent to the mitral annulus
Because the apex remains relatively stationary throughout the cardiac cycle,

18. Wave forms The cardiac cycle is represented by 3 waveforms
Sa - systolic myocardial velocity above the baseline as the annulus descends toward the apex
Ea - early diastolic myocardial relaxation velocity below the baseline as the annulus ascends away from the apex
Aa - myocardial velocity associated with atrial contraction.

19. Doppler tissue imaging using a spectral display and a single area of interest targeted to the lateral mitral valve anulus. The location of the sample volume is noted by the arrow and in this instance is in the lateral anulus. The systolic motion of the anulus (Sa) and the diastolic anular motion (Ea and Aa) are as noted.

20. Measurement of peak myocardial systolic (Sm), early diastolic (Em), and late diastolic (Am) velocities, as well as the time to peak systolic velocity in ejection phase (Ts) at basal septal and basal lateral segments by 2-dimensional color-coded tissue Doppler imaging in a normal subject (

21. PARAMETERS OF TDI

22. Normal Doppler pattern
Sm (cm/sec)
Em (cm/sec)
Am (cm/sec)
Septal
Lateral
Septal Systolic velocities lower than free wall Sm
Em / Am more than one, similar to E/ A in mitral flow
Peak velocities at base and decrease towards apex
Age related reduction in peak velocities Sm and Em
Em/ Am reversal after age of 50

23. Color TDI
Color-coded representation of myocardial velocities is superimposed on gray-scale 2-dimensional or M-mode images
indicate the direction and velocity of myocardial motion
increased spatial resolution and the ability to evaluate multiple structures and segments in a single view.
Color TDI mode has the advantage of

24. septum moves posteriorly, it is encoded in blue, and as the posterior wall moves anteriorly in systole, it is encoded in red

25. M-mode color Doppler tissue imaging
Color -encoded images of tissue motion along an M-mode interrogation line
Represents a combination of M-mode echocardiography, color Doppler imaging, and quantitative Doppler tissue imaging
High temporal and spatial resolution
Determining velocity gradients between adjacent points or more recently for strain rate imaging

26. individual with normal contraction
individual with normal contraction. Note that motion toward the transducer is color encoded in red and that oriented away from the transducer is in blue. For this reason, normally contracting walls that move opposing directions are color encoded in opposite colors. Also note the excellent temporal resolution for determining the timing of contraction.

27. Endocardial-epicardial gradient
DTI sample volume in the subendocardium, & subepicardial
Difference between velocities -endocardial-epicardial gradient.
Alterations ,with a selective decrease in the subendocardial velocities --very sensitive marker of ischemia
determined in a single segment with the same angle of interrogation of the Doppler beam- relatively angle independent
Derivation of doppler tissue velocity

29. Strain Lo Strain rate :- rate of deformation
Deformation of the myocardium on application of stress
Change in distance between two points divided by the initial length (L0).
expressed as percentage L-Lo Lo
Strain rate :- rate of deformation
Integration of Strain Rate gives strain

30. Strain rate
Derivative of DTI provides a high-resolution evaluation of regional myocardial function
sensitive and earlier indicator of regional dysfunction

31. With DTI simultaneously determine velocities in two adjacent points & relative distance in between
Defined as the instantaneous rate of change in the two velocities divided by the instantaneous distance between the two points.
Positive strain rate represents active contraction and negative values, relaxation or lengthening between the two points.

33. Clinical Applications of TDI

34. Assessment of LV Systolic Function
Systolic myocardial velocity (Sa) at the lateral mitral annulus measure of longitudinal systolic function
Correlated with LV ejection fraction
Mitral annular displacement Velocity reduced in LV dysfunction
Regional reductions in Sa - regional wallmotion abnormalities.
Advantage in suboptimal echo window

35. Note that in heart failure there is a reduction of Sm and Em
Note that in heart failure there is a reduction of Sm and Em. Systolic dyssynchrony is demonstrated by the delay of Ts in the basal lateral segment when compared with the basal septal segment.

36. Assessment of Diastolic Function
Mitral inflow patterns are highly sensitive to preload
mitral valve inflow patterns to assess diastolic function remains limited
TDI assessment of diastolic function is less load dependent

37. Lateral annulus most commonly used
Ea - reflects the velocity of early myocardial relaxation as the mitral annulus ascends during early rapid LV filling.
Peak Ea velocity - measured from any aspect of the mitral annulus from the apical views
Lateral annulus most commonly used
Septal Ea velocitiy slightly lower than lateral Ea velocities
Because of intrinsic differences in myocardial fiber orientation

38. Reductions in lateral Ea velocity to ≤ 8 cm/s in older adults indicate impaired LV relaxation
Differentiates normal from a pseudonormal mitral inflow pattern
Unlike conventional mitral inflow patterns, Ea is resistant to changes in filling pressure

39. Em / Am < 1
Em <8 cm/sec

42. CAD
Reduction in Sa velocity can be detected within 15 seconds of the onset of ischemia
Ischemia low systolic and diastolic velocities
<7.5cm./sec LV wall velocity - WMA
Em/ Am reversal

43. TDI Stress Echo
Incorporation of TDI measures of systolic function in exercise testing to assess for ischemia
Peak Sa velocity increases with dobutamine and exercise and decreases with ischemia
Better identification of abnormal segments
Better reproducibility than standard Echo
Peak velocity < 5.5 cm/sec identify abnormal segments
96% sensitivity, 81% specificity Katz et al
The technical difficulties of timely acquisition of both 2-dimensional and TDI data during exercise
represent the major limitations to routine integration in stress testing.

44. Novel Applications of TDI
A number of emerging applications for TDI are under active investigation

45. Estimation of LV Filling Pressures
LV filling pressures are correlated with the ratio of the mitral inflow E wave to the tissue Doppler Ea wave (E/Ea)
E/lateral Ea ≥ or E/septal Ea ≥ 15
-- elevated LV end-diastolic pressure,
E/Ea ≤ 8 is correlated with a normal LV EDP
E/Em > 10 predicted PCWP > 15 mm of Hg
with 92% sensitivity and 82% specificity Nagueh et al
Simultaneous cardiac catheterization and echocardiographic studies have shown that

46. Differentiation Between Constrictive and Restrictive Physiology
Constrictive pericarditis and restrictive cardiomyopathy -- abnormal LV filling
In the absence of myocardial disease, Ea velocities typically remain normal.
intrinsic myocardial abnormalities - impaired relaxation and reduced Ea velocities.
characteristic of restrictive cardiomyopathy result

47. Constriction Vs Restriction
Em < 8 cm/sec restriction
>8 constriction
Garcia et al

48. Early Diagnosis of Genetic Disease
unexplained LV hypertrophy is typically required to diagnose hypertrophic cardiomyopathy (HCM)
degree of hypertrophy and age of onset are highly variable
Abnormalities of diastolic function-reduction of Ea velocities
Sarcomere gene mutation ;before the development of LV hypertrophy
Early stages of Fabry disease.
Reduced Ea velocities have been similarly demonstrated in patients in the

49. Differentiation of Athlete’s Heart From HCM
Approximately 2% of athletes abnormal degree of LV hypertrophy
Discriminating physiological hypertrophy due to intense athletic conditioning from pathological
Athletes highly compliant ventricles with brisk Ea velocities
reduced Ea velocities in individuals with HCM

50. Assessment of Cardiac Dyssynchrony
Identifying patients who will benefit from cardiac resynchronization therapy which can improve heart failure
TDI can be used to assess the relative timing of peak systolic contraction in multiple myocardial regions
standard deviation of the time to peak contraction represents a measure of overall ventricular synchrony

51. identify potential responders to cardiac resynchronization therapy

52. Assessment of Right Ventricular Function
important prognostic indicator in patients with heart failure and in postinfarction patients
Reduced tricuspid annular velocities with TDI have been documented in a variety of disease settings
Post inferior myocardial infarction chronic pulmonary hypertension, and chronic heart failure
The complexity of right ventricular anatomy and geometry challenges accurate assessment of right ventricular systolic function

53. TDI Consider complimentary to the std. Echo
Important in diastolic function assessment
TVI obtain data even in suboptimal 2D windows
Less inter observer variation
Quantitative than qualitative
Better regional assessment
Assessment of myocardial asynchrony

54. Strain rate imaging Better regional assessment than TVI
Better predictor of LV function than TVI
Better predictor of ischemia

55. THANKU