1. TISSUE DOPPLER IMAGING
DR PRASANTH S

2. Introduction
TDI uses Doppler shift data from the myocardium to obtain qualitative and quantitative information on myocardial wall motion.
Measures the velocity of myocardial wall motion
Low velocity
5 to 20 cm/s
10 times slower than velocity of blood flow
High amplitude
Approximately 40 decibels higher than blood flow
IntJ of Card Imaging 2001;17::8

3. 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.

4. 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.

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

6. 2D Colour TDI
Colour-coded representation of myocardial velocities- superimposed on gray-scale 2-dimensional 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

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

8. M-mode colour Doppler tissue imaging
Colour-encoded images of tissue motion along an M-mode interrogation line.
High temporal and spatial resolution.

9. Pulsed-wave TDI Used to measure peak myocardial velocities
Mitral annular motion: Good surrogate measure of overall longitudinal left ventricular contraction and relaxation.
To measure longitudinal myocardial velocities, the sample volume is placed in the ventricular myocardium immediately adjacent to the mitral annulus
TDI can be performed in pulsedwave and color modes.

10. Pulse Wave Tissue Doppler

12. Diastolic components of myocardial velocities correlate with mitral inflow velocities

13. Normal Myocardial Velocities : Basal Segments (cm/s)
J Am Soc Echo 2001;14:

14. Myocardial Velocity Gradient
Difference in myocardial velocity between the endocardium and epicardium divided by the myocardial wall thickness
Reflects rate of change in wall thickness
MVG is an indicator of regional myocardial contraction.
Determined in a single segment with the same angle of interrogation of the Doppler beam- relatively angle independent
J Am CollCard 1995; 26:217-23

16. Clinical Applications of TDI

17. Assessment of LV Systolic Function
Sa- Correlated with LV ejection fraction.
Peak systolic velocities were measured at 4 different sites of the mitral annulus.
A cut-off point of ≥ 7.5 cm/s had a sensitivity of 79 % and a specificity of 88 % in predicting preserved systolic function or ejection fraction of ≥ 0.50.
Regional reductions in Sa - regional wall motion abnormalities.
J Clin Basic Cardiol 2002; 5: 127

18. Regional Systolic Function
Pulse wave tissue Doppler after anteroseptal MI.
Decreased velocity in the septum (top).
Normal velocity in the lateral wall (bottom).

19. Diastolic Dysfunction
Impaired relaxation
Pseudonormal
Restrictive

20. Transmitral flow velocities are dependent on LA filling pressures.
Psuedonormalization occurs as LA pressure increases.
Difficult to diagnose diastolic dysfunction from mitral flow velocities.
Myocardial velocities are persistently reduced in all stages of diastolic dysfunction.
TDI assessment of diastolic function is less preload dependent.

21. Diastolic Dysfunction
NORMAL
Impaired Relaxation
Pseudonormal
Restrictive Filling DT
<220 ms
>220 ms ms
<150
E/A
1-2
<1
>2 Em
> 8
< 8

22. Diastolic Dysfunction

23. 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/E’)
E/lateral E’ ≥ 20 - elevated LV end-diastolic pressure.
E/E’ = is correlated with a normal LV EDP
E/E’ > 20 predicted PCWP > 15 mm of Hg
with 92% sensitivity and 82% specificity Nagueh et al
Simultaneous cardiac catheterization and echocardiographic studies have shown that

24. Constrictive Vs Restrictive Physiology
Constrictive pericarditis with normal LV function have normal or elevated Em velocities.
Doppler Em velocity of 8 cm/s differentiates constriction and restriction.
Restrictive < 8 cm/s
Constrictive > 8 cm/s
characteristic of restrictive cardiomyopathy result

26. 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 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

27. Limitations
Accuracy of velocities dependent on angle of ultrasound beam.
Not all wall velocity obtainable from every view.
Wide range of normal values.
Even non contractile myocardium will be pulled by near by segments resulting in apparent velocity component.

28. Strain Rate Imaging

29. Introduction
Evaluation of a myocardial region with reference to an adjacent myocardial segment.
Deformation analysis- analysis of ventricular mechanics or shapes during cardiac cycle.
Myocardial strain, strain rate, torsion.
Strain- percentage thickening or deformation of the myocardium during the cardiac cycle.
Change of strain per unit of time is referred to as strain rate

30. Strain calculated in three orthogonal planes- representing longitudinal, radial, circumferential contraction.
Negative strain- shortening of segment.
Positive strain- lengthening of segment

32. Strain & Strain rate

34. Methods Doppler tissue imaging
Two discrete points are compared for change in velocity
Strain rate- primary parameter obtained
Strain –derived by integrating velocity over time.
Speckle tracking
Actual location of discrete myocardial segments calculated.
Strain is the primary parameter.
Strain rate-derived by calculating change in distance over time.

35. Comparison of Two-Dimensional Speckle Tracking Echocardiography (2D STE) with Tissue Doppler Imaging (TDI)
2D STE
TDI
Deformation analysis in 2 dimensions .
One-Dimension measurements
Angle independent
Measurement dependent on angle
Better spatial resolution
Limited spatial resolution
Less time-consuming data acquisition and easy data processing.
Time-consuming
Lower temporal resolution
High temporal resolution
Dependent on high resolution image quality
Image quality less important
Lower interobserver variability
Higher interobserver variability
Lower optimal frame rate limits the reliability of measurements in patients with tachycardia

37. SR- Doppler tissue imaging

38. Speckle tracking
‘Speckles’ are small dots or groups of myocardial pixels that are created by the interaction of ultrasonic beams and the myocardium.
Considered as acoustic fingerprint for that region.
This enables to judge the direction of movement, the speed of such movement, and the distance of such movement of any points in the myocardium.

39. Speckle

40. Method
Track the endocardial and epicardial borders of the left ventricle
Correctly define the region of interest (ROI) in the long or short axis view
Post-processing software automatically divides the ventricle into six equally distributed segments
2D or 3D data set is produced
Mathematical algorithms are applied to generate values

41. Strain is not uniform among all myocardial segments.
Radial strain-Magnitude of basal parameters are higher than the apical values.
Longitudinal strain- less variability fron apex to base.
Circumferential strain- higher in anterior and lateral walls compared to posterior and septal.
Normal longitudinal strain averages -20%
Normal radial strain about +40%

43. Normal Strain Displays Wave Forms ,Curved M-mode

44. Normal Strain Displays- bulls eye presentation

46. Normal pattern
Dilated cardiomyopathy
Dyssynchrony

47. Velocity vector imaging

48. Cardiac muscle 3 layers- middle transverse layer.
inner oblique layer(descending segment)
outer oblique layer( ascending segment)

49. VENTRICULAR TORSION Similar to the winding and Unwinding of a towel.
Isovolumetric contraction -the apex and base rotates in counterclockwise direction.
Ejection phase apex rotates counterclockwise & base rotates clockwise when viewed from the apex
Diastole - relaxation of myocardial fibres - recoiling - clockwise apical rotation.
Isovolumetric relaxation- both apex and base rotates in clockwise direction.

50. Myocardial mechanics

51. Rotation - Measure of the rotational movement of the myocardium in relation to an imaginary long axis line from apex to base drawn through the middle of LV cavity.
Twist (degrees) is the net difference between apical and basal rotation
Torsion - Twist divided by the vertical distance between the apex and base and is expressed as degrees/cm.

52. VENTRICULAR TORSION

53. CAD- Myocardial ischemia, Myocardial infarction, Myocardial viability
Reduction in strain by 2D STE more objective and accurate than the traditional visual method of assessing WMA.
Post systolic thickening (deformation)by radial strain correlates with the severity of ischemia.
To differentiate transmural from subendocardial infarction- lower circumferential strain in the former

54. Applications Heart failure with normal LVEF
Reduced and delayed LV untwisting—at rest and exercise
Cardiac resynchronization therapy (CRT)
Speckle Tracking and Resynchronization (STAR) study showed radial and transversal strain better than longitudinal and circumferential strain in predicting LVEF response and long term survival after CRT.
Lack of dyssynchrony before CRT by 2D STE radial strain associated with death or hospitalization for heart failure

55. Twist in DCM
Am J Cardiol 2008;101:1163–1169, 2008

56. Applications Valvular heart disease- Stress cardiomyopathy.
Restrictive cardiomyopathy.
Detection of subclinical diseases/early myocardial involvement.
Detection of rejection and coronary stenosis in heart transplant patients.
Early detection of chemotherapy induced cardiotoxicity.
Valvular heart disease-
Decreased radial, circumferential and longitudinal strain in patients with severe aortic stenosis and normal LVEF. Long term follow up after valve replacement showed significant improvement in strain.

57. Differentiation of Athlete’s Heart from Hypertrophic Cardiomyopathy
Normal longitudinal and other
types of strain
Decreased longitudinal strain
Increased LVEDV
Decreases after deconditioning for 3 months.
Decreased LVEDV
No change with deconditioning.
Increased LV twist.
Delayed LV untwisting.
Increased early LA strain rate.
Reduced LA strain and
strain rate