This document discusses the evolution and clinical applications of strain imaging using echocardiography. Strain imaging allows quantitative analysis of myocardial deformation and function beyond what can be seen with conventional echocardiography. It describes how speckle tracking can measure longitudinal, radial, and circumferential strain to assess different regions of the heart. Clinical uses of strain imaging include early detection of chemotherapy-induced cardiomyopathy and assessment of valvular heart disease before changes in ejection fraction occur.

1. Evolution of Echocardiography

2. STRAIN
IMAGING

3. CASE 1
65 year old male is a K/C/O
HTN (5 years), smoker with
family history of CAD present
presented with complaints of
angina on exertion since 3
months.
ECG- Normal
Echo- normal study.
CAG- Normal coronaries.
CASE 2
65 year old male is a K/C/O
HTN (5 years), smoker with
family history of CAD present
presented with complaints of
angina on exertion since 3
months.
ECG- Normal
Echo- normal study.
CAG- TVD.

4. INTRODUCTION
• Echocardiogram is a standard procedure in
evaluation of LV function.
• Conventional echocardiography is considered to be
reliable for regional wall motion analysis.
• Visual estimation of wall motion is very subjective
& therefore highly operator dependent.
• High interobserver & intraobserver variability

5. • Also some patients had no visual segmental
wall motion abnormalities at rest despite
having significant CAD on angiography.
• Strain imaging is a new tool to measure
myocardial deformation and allow quantitative
analysis of global and regional myocardial
function

6. • Deformation- Any change in shape.
• Strain - percentage change in myocardial
deformation.
ε= L-L0/L0
L - length of the object after deformation,
L0 is the basal length of the object.

8. Depending on the direction :-
• shortening/ thinning of segment- Negative
strain,
• thickening/ lengthening of segment- Positive
strain

10. Strain Rate
• Rate of change of deformation of a myocardial
segment over time.
• Strain rate- strain/ ∆ time
• It is expressed as seconds−1;
• Noisier and less reproducible & most clinical
studies use strain measurements.

11. • At baseline
• A) 10 cm
• B) 10cm

12. • At 2 second
• A) 20cm
• B) 15 cm

13. • At 2 second
A) 20cm
• Strain -20-10/10= 100%
• Strain Rate- 1/2= 0.5 per second
At 4 second
B) 20 c 20cm
Strain -20-10/10= 100%
Strain rate 1/4 = 0.25 per second

14. • Myocardial Tethering
• Dysfunstional segment is pulled by active
segment.
• 2D echo cant differentiate b/w active and
passive movement.
• Strain/ strain rate can differentiate which is
actually pulled and not contracting

15. Three aspects
• Velocity- How fast/ slow myocardial segment
is contracting.
- cm/sec
• Strain- Total amount of contarction that has
occurred.
- percentage
• Strain rate- At what rate it is contracting
- per second.

16. • Strain calculated in three orthogonal
planes- representing
• Longitudinal - negative (shortening)
• Radial – positive (thickening)
• Circumferential – negative (shortening)

18. Longitudinal Strain-
• Shortening of LV along its long axis
• Directed from the base to the apex, during systole.
• Represented by negative trend curves on speckle tracking
• Measured from 4-chamber, 2-chamber, and apical long-axis
views, both regional (relative to each of the 17 LV
segments) and global strain values (global longitudinal
strain) can be obtained.

20. Radial Strain
• Thickening of LV wall along its radius, during
systole
• Obtained in basal and apical LV short-axis
views.
• represented by positive trend curves on
speckle tracking

22. Circumferential Strain
• Reduction in the circumference of LV cavity,
during systole
• Circumferential strain represented by negative
curves.
• Measured from short axis view

24. Rotational strain
• LV rotates around its long axis.
• During systole, apex rotates in anticlockwise direction &
base rotates in clockwise direction.
• Measured from short axis view.
• By convention, anticlockwise rotation is displayed above
the baseline and is assigned a positive value whereas the
opposite is true for the clockwise rotation. Thus, the normal
apical rotation is positive and the basal rotation is negative.

25. Myocardial mechanics

26. Arrangement of myofibers in Myocardium
• Inner subendocardial fibres are
oriented parallel to the long axis of
LV and hence predominantly help
in longitudinal contraction.
• Mid-myocardial & subepicardial
fibers are arranged parallel to the
circumference of LV & hence help in radial,
circumferential & rotational movement.

27. • Epicardial coronary artery stenosis is a/w reduction
in the subendocardial to subepicardial flow ratio.
• Subendocardium layer of the heart is most
vulnerable to ischemic damage.
• The subendocardial region consists of
longitudinally directed fibers, significantly
contributing to long axis function.
• As a result; longitudinal function is impaired first in
CAD.
• Measurements of longitudinal motion and
deformation are therefore, the most sensitive
markers of CAD

28. • RS & CS remain preserved or may even be
accentuated during the early stages to compensate
for the loss of the longitudinal function.
• As the disease becomes more extensive/ more
transmural, RS & CS also get progressively
impaired.
• Thus, the impairment of RS & CS is a relatively
late phenomenon and tends to reflect more
extensive myocardial damage.
• However, in certain pathological conditions that
affect the heart from the outside, such as
constrictive pericarditis, CS & RS may get
compromised earlier than the LS.

29. 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.

30. SR- Doppler tissue imaging

32. 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

33. Speckle tracking
• Analysis of the spatial dislocation (referred to as tracking)
of speckles on routine 2-dimensional sonograms.
• ‘Speckles’ are small dots or groups of myocardial pixels
that are created by the interaction of ultrasonic beams and
the myocardium.
• Judge the direction of movement, the speed movement, &
the distance of movement of any points in the
myocardium.

34. Speckle

35. How to perform speckle tracking
echocardiography
Image acquisition
• Obtain high quality gray scale image, wherein
endocardial & epicardial border is well defined
• Apical 4, 3 & 2 chamber for Longitudinal strain.
• Short axis view at basal, mid & apical levels for
radial, circumferential & rotational strain.
• For LA strain, apical 4, 3 & 2 chamber view
• For RV strain, RV focused apical 4 chamber view

36. • Optimal frame rate - 60 and 110 frames/
second.
• High quality ECG signal for proper gating of
images
• Minimal 3 cardiac cycle should be acquired.
• All images should be acquired in breath- hold
to avoid any breathing artifacts.

37. Image Analysis
• Begin with an apical 3 chamber view. In this AV
movement help in timing the AVC, essential to
perform deformation analysis.
• When the image is opened in software, software
automatically brings up end systolic frame.
• In this, endocardial border is traced manually,
beginning at one end of the mitral annulus and
ending at the other end.

38. • The software then generates a region of
interest (ROI) to include the entire myocardial
thickness.
• Width of ROI can also be manually adjusted.
• Software then track the myocardial speckles
frame by frame and generates moving images
displaying the tracking.
• Software then divides the LV myocardium into
seven segments and generates segmental and
global longitudinal strain & strain rates.

41. • Same process is repeated with apical 4 & 2
chamber images.
• Strain values for all the segments are recorded
& averaged to obtain the global longitudinal
strain.
• Also provide Bull’s eye display of the regional
& global longitudinal strain.

42. Normal Strain Displays- bulls eye
presentation

44. • Short axis is also analyzed in the same manner
to get the segmental & global radial &
circumferential strain & strain rate.

45. Interpretation
• Among all the strain parameters, longitudinal
strain is more reproducible than the radial &
circumferential strain & rotation.
• Similarly, global strain has much better
reproducibility than the segmental strain.
• The normal GLS is usually in the range of - 16 to
-18% or more (i.e. more negative).

46. • The circumferential strain is usually greater than the
longitudinal strain with average values in excess of -20%.
• The average radial strain is in the range of +40 to +60%.
• The rotation strain has much greater variability which
makes it difficult to define the normal ranges for the same.
However, it should be noted that the apical rotation is
normally much greater than the basal rotation which is
limited by the tethering effect of the mitral annulus

47. • The maximum LS, CS & RS during systole is
termed as peak systolic strain (peak LS, peak
CS & peak RS).
• Average strain during systolic phase is termed
as mean LS, mean CS & mean RS

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

52. Clinical application
1. Detection of subclinical myocardial dysfunction
 Fall in the LVEF represents a relatively late stage
when sufficient myocardial damage has already
occurred.
Detection of the myocardial dysfunction in
subclinical stage may have significant diagnostic and
therapeutic implications .

53. a) Chemotherapy induced cardiomyopathy
• Impairment of GLS despite preserved LVEF in
patients receiving cancer chemotherapy may
warrant discontinuation of the treatment regimen.
• One study found that reduction of LS by 10%
predicts decline in LVEF in subsequent 6 month
with sensitivity of 78% and specificity of 79%

55. b) Valvular heart disease
• In MR/AR, LV respond to increase in volume
overload by dilatation & in AS respond to
pressure overload by hypertrophy.
• This maintain LV sysytolic function & could
mask subcliniacal LV dysfunction.
• Evidence of early myocardial damage in
patients with severe AS/MR may help in
timing the surgical intervention in these
patients & can prevent irreversible myocardial
damage.

56. • Impaired LS is the first sign of myocardial
dysfunction in chronic VHD f/b impairement
of RS & CS as disease progressed.
• Also strain have been shown to improve after
surgical intervention.

57. Also helpful in documenting cardiac involvement
in a variety of disorders such as HTN, DM,
obesity, OSA, amyloidosis, Fabry’s disease, etc.
• Varghese MJ et al. (2016, AIIMS), GLS was
significantly reduced in patients with OSA
(p < 0.01).
• Segmental analysis revealed that the LS
abnormalities are more pronounced in the apical
and mid segments of LV.

59. Differentiating HCM from Athletes’ heart.
HOCM
- Decrease LS strain with preserved CS strain
Athlete’s Heart
• Increase LV hypertrophy lead to increase LV mass
with preserved or increase LV systolic & diastolic
function.
• STE showed increase in LS.
• Some study showed increase in RS & CS

61. 2) As a surrogate for LVEF
• For estimation of LVEF from GLS using the in-built
regression equation.
3) Monitoring response to treatment
• GLS can be used for monitoring improvement in LV
contractile function after myocardial revascularization
/ stem cell therapy /drugs etc.

62. 4) Role in acute coronary event
• LS is reduced in infarcted segment proportional to
the area of infarcted region. Hence predict infarct
size
• In subendocardial infarct, only LS is reduced with
preservation/ accentuation of RS & CS, While in
transmural infarct, CS & RS is also impaired.

63. • Becker et al. have shown that segmental RS <
+16.5% & CS < -11.1% can differentiate
nontransmural infarction from transmural
infarction with sensitivity of 70% & specificity of
71.2%.
• He also found that RS > +17.2% indicate good
functional recovery after reperfusion.

64. 5) As a measure of myocardial ischemia and viability
• LS, when combined with DSE, improves the accuracy
of assessment of myocardial ischemia and viability.
• Augmentation of strain & strain rate with dobutamine
is a marker of myocardial viability.
• The resting GLS has also been shown to be a predictor
of myocardial viability.

65. • In one study, it is found that RS cut off value
17.2% could predict a viable myocardium with
sensitivity of 72% & specificity of 85% (similar
to CE-MRI).
• Another study (Park et al.), found that LS value <
-10.2% following reperfusion therapy aftetr MI
predicts non viable myocardium with sensitivity
of 90% & specificity of 85%.
• In addition, impairment in CS also indicates lack
of myocardial viability as it reflects greater
transmural extent of the infarct.

66. DCMP
• Impairement of all three directional
strain(LS/RS/CS)
Stress cardiomyopathy
• Reduction in various LV strain that extend
beyond the single coronary artery territory &
improvement in these finding at recovery.

68. Heart Transplant patients
• Marciniak et al. found significantly lower LV
LS & RS strain rate in patients with acute
rejection.
• Fusaka sera et al. found that LS <11% could
predict cellular rejection with sensitivity of
40% and specificity of 90%

69. 6) Role in cardiac resynchronization therapy
• Radial strain has been shown to be a robust
measure of intraventricular mechanical
dyssynchrony & a reliable predictor of the
response to CRT therapy.
• Time to peak radial strain can also help in
identifying the site of least activation and thus help
in guiding the LV lead placement.
7) Assessment of LV diastolic function
• Early diastolic strain rate, peak untwist velocity
and time to peak untwist velocity have all been
used as measures of LV diastolic function with
variable results.

70. 8) Assessment of RV function
• RV longitudinal strain has been shown to be a
reliable measure of RV systolic function in a variety
of clinical conditions such as pulmonary embolism,
RVMI, pulmonary hypertension, RV
cardiomyopathies, congenital heart diseases like
TOF, pulmonary atresia with intact IVS & TGA,
tricuspid atresia, DORV & AV canal defect etc.

71. LA function
• Reduced peak atrial LS is observed in:-
-LV diastolic dysfunction
- atrial septal device occlusion
- who have undergone catheter ablation/
cardioversion

72. 10) RA Strain
• Not much study.
• One study showed that in DCMP patient with
CRT for dyssynchrony, peak right atrial LS is
much lower in non-responder (24+10%) in
comparison to responder (40+8%).
11) Other uses
• As mentioned earlier, early impairment of
circumferential strain may help in
differentiation between constrictive
pericarditis and restrictive cardiomyopathy.

73. Limitation
There are a number of factors that affect
measurement of LV strain. These include
physiological factors such as age, gender etc
Other limitation are :-
1) image quality
-Highly dependent on 2D image quality.
-With suboptimal acoustic window, STE fail
to quantitate strain correctly.

74. 2) Heart rate
- Mismatch of temporal & spatial resolution at higher
heart rate, leading to underestimation of strain & SR.
3) Vendor viability
• - measurements obtained on one ultrasound
system are not identical to the measurements
obtained on another ultrasound system.
• For these reasons, no universally accepted normal
values are available for the different myocardial
deformation parameters.

75. 3-D Speckle Tracking Echocardiography
• 2D STE is based on the assumptions that speckles
always confined within the 2D images.
• This is not always valid because 3D motion of
cardiac chambers.
• 2D STE unable to measure one of three component
of displacement vectors & this affect the accuracy of
various derived strain.
• In comparison, 3D STE result in more homogenous
spatial distribution of various myocardial strain

76. • 3D STE estimated strains showed more interobserver,
intraobsever & test-retest reproducibility.
• Show greater correlation with MRI than corresponding 2D
derived strain.
• In addition, global deformation indices can be obtained in a
shorter span of time by obtaining a single large 3D volume.
• Finally, 3D strain exclusively allows for the measurement of
“area strain (AS),” defined as longitudinal strain ×
circumferential strain, providing additional information on
global myocardial function.

77. • Dillikar MV et al. (2017, Sri Satya Sai) found
that the sensitivity of GLS for CAD was 80% for
2D versus 93% for 3D STE.
• Similar findings were seen for global
circumferential strain (sensitivity 87% for 2D vs.
100% for 3D).
• However, the sensitivity of 3D global radial strain
was lower (93% for 2D vs. 47% for 3D).

81. Flow chart
Patients who meet the inclusion criteria for study admitted to BHMRC will be enrolled
Eligible cases
Routine demographic,clinical,biochemical and ECG assessment
2D echocardiography (Global peak LV strain,, LVEF,)

82. • All patients will undergo Coronary Angiography
Statistical Analysis
Outcome:whether 2Decho parameters of LV function helps in ruling out significant
CAD
Group 1
CAD present= Gensini score
Group 2
CAD absent

83. Hypothesis
With this study we hypothesized that global
longitudinal peak systolic strain (GLPSS)
correlates inversely with coronary artery disease
severity and a reduced GLPSS may be able to
predict high Gensini Score in patients
undergoing coronary angiography, whose resting
echocardiogram failed to detect any regional
and/or global wall motion abnormalities.

85. Normal pattern
Dilated cardiomyopathy
Dyssynchrony

86. Velocity vector imaging

87. Cardiac muscle
• 3 layers-
1) middle transverse layer.
2) inner oblique layer(descending segment)
3) outer oblique layer( ascending segment)

88. 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.

89. • 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.

90. VENTRICULAR TORSION

91. 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

92. 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

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

94. Applications
• 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.

95. Differentiation of Athlete’s Heart from
Hypertrophic Cardiomyopathy
Athlete’s Heart 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

96. 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

98. Why Global Longitudinal Peak Systolic Strain?
• The subendocardium is often the earliest
myocardial layer affected in many disease
processes.
• It is the furthest layer from epicardial coronary
flow
• It undergoes extreme fluctuations in pressure and
compression in both systole and diastole
• Appears prone to early structural microvascular
architectural change

100. Measurement of GLPSS

101. Speckle tracking : Strain
• Tissue imaging evaluation myocardial
deformation
• Good Quantitative assessment
• Angle independence
• Validated to CMR and Sonomicrometry
• Minimal bias ( low intra and interobserver
variability)

103. • Speckle tracking measures strain and strain rate.
• Strain is defined as the percentage change in
myocardial deformation and its derivative,
• The strain equation (ε) is as follows:
ε=L-L0/L0
• where L - length of the object after deformation,
• L0 is the basal length of the object

104. Strain & Strain rate

105. • How to Obtain Strain Parameters
• performed offline,.
• The optimal frame rate - 60 and 110 frames/ second.
• Begin with an apical 3 chamber view to select the
frame corresponding to the aortic valve closure,
followed by apical 4-and 2-chamber view acquisitions.
• The endocardial surface of the myocardial segment
analyzed is manually traced by a point-and-click
approach.
• An epicardial surface tracing is then automatically
generated by the system, thus creating a region of
interest.

106. • After manual adjustment, the software
automatically divides the region of interest into 6
segments, and the resulting tracking quality for
each segment is automatically scored as either
acceptable or unacceptable, with the possibility of
further manual correction.
• Once the region of interest is optimized, the
software generates strain curves for each selected
myocardial segment.
• From these curves, the operator can obtain regional
and global peak and time-to-peak values.

107. • the software also automatically generates a
topographic representation of all 17 analyzed
segments (bull's-eye).

108. Application
• Diabetes- detecting subclinical LV systolic
dysfunction, which is unmasked by the alteration
of longitudinal strain.
• Valvular heart disease
Inpatients with degenerative mitral
regurgitation undergoing valvular surgery, speckle
tracking showed post surgery LV dysfunction.
In patients with AS/ AR immediately
after AVR, there is a substantial increase in radial
and circumferential strain, suggestive of how these
myocardial deformation parameters critically
depend on LV load conditions

109. • Heart failure
LV longitudinal strain progressively
deteriorates from NYHA I to class IV, with
additional LV radial and circumferential systolic
impairment occurring in NYHAclasses III and IV

110. • Other Application
• Early detection of doxorubicin induced cardiac
injury.
• Useful in quantification of LV systolic function
in athletes and the differentiation of physiologic
hypertrophy in athletes’ hearts from
asymptomatic nonobstructive hypertrophic
cardiomyopathy, which is the major cause of
sudden cardiac death in young competitive
athletes.

111. • Also be used to differentiate physiologic cardiac
hypertrophy (“athlete’s heart”) from hypertensive
cardiac hypertrophy
• Also useful for the evaluation of right ventricular
(RV) function in pulmonary hypertension and RV
diseases of different etiologies (RV infarction,
arrhythmogenic RV dysplasia/ cardiomyopathy)

112. • Mean longitudinal LV strain is closely related to
plasma BNP levels, in patients with both systolic
and diastolic heart failure.
• Sensitive indicators for sub-clinical diseases,
including diabetes, systemic sclerosis, myocardial
ischemia, arterial hypertension, isolated mitral
regurgitation, aortic regurgitation and non-
ischemic cardiomyopathies.
• Useful for the assessment of myocardial damage
after infarction, evaluation of myocardial
revascularization efficiency and prediction of
patient outcome with heart failure.

113. • Augmentation of strain and strain rate with dobutamine is a
marker of myocardial viability and hence can improve the
diagnostic and prognostic assessment of myocardial
ischemia and post-infarction scars during dobutamine stress
echocardiography.
• In patients with chronic ischemic LV dysfunction it was
shown that combined assessment of long-axis and short-axis
function using 2Dstrain imaging may be used to identify the
transmural extent of myocardial infarction

114. Following parameters of the left ventricle will be
determined from apical two-chamber, three-
chamber and four-chamber view:
Global peak systolic longitudinal strain
 LV ejection fraction (LVEF) will be
calculated using Simpson’s method.