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 Figure 4-10: Segment scoring
1. Selected segment
2. Selected score
1. Scored segment 
						

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Blood pressure monitoring
The blood pressure (systolic and diastolic) for the selected view 
is displayed over the scoring diagrams (Figure 4-10).
1. Press BP.
The blood pressure 
data in the dialogue 
window can be edit-
ed.the systolic and diastolic blood pressure data for all levels 
is displayed in a dialogue window. 
						

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Quantitative TVI Stress echo analysis
The Vivid 7/Vivid 7 PRO Ultrasound unit provides a 
Quantitative TVI (QTVI) Stress analysis package based on 
Tissue velocity information (TVI). The TVI data is stored in a 
combined format with grey scale imaging during stress 
examination.
When selecting a template supporting TVI data acquisition, the 
ultrasound unit will automatically store TVI information, 
generally for the apical views of the stress examination.
The QTVI Stress analysis option currently applies only to 
Dobutamine stress-echo.
Wall Motion Scoring remains the basis for the diagnosis of CAD 
in stress echocardiography. QTVI Stress may be used as a 
guidance tool to check this interpretation.
The current version of QTVI Stress is based on the assessment 
of peak velocity at peak Dobutamine stress (see reference 1 on 
page 176). The normal ranges have been validated in the 
“average” patient presenting for stress testing. The velocity 
cutoff values for the Vpeak measurement will not work in the 
following cases: 
•  Submaximal stress (
						

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Velocity measure-
ments in mid and 
basal segments of 
the myocard will 
contain contribu-
tions from the api-
cal region of the 
myocard. E.g. if 
measured value in a 
mid segment is be-
low the cutoff value 
for this segment 
then this might re-
late to a reduced 
function in the mid 
or apical region.The velocity cutoff values are based on placing the sample 
volume at center of each cardiac segment at start of systole, 
the left ventricle myocardial segments are defined by the 
American Society of Echocardiography 16 segments model. 
However, the velocity cutoff model does not cover the apical 
segments (due to low velocities and segment orientation), (see 
side note).
Tissue Doppler does not have perfect site-specificity because 
of tethering by adjacent segments. Thus, although an ischemic 
segment has little thickening (and therefore could be expected 
to show low velocity), measured velocity may be influenced by 
local tethering, reflecting contraction in surrounding segments. 
Conversely, a normal segment may have its velocity reduced 
by an adjacent segment with reduced velocity. This tethering 
effect may decrease the sensitivity for single vessel disease, 
but nonetheless the sensitivity and specificity of the cut-offs are 
approximately 80% (see reference 1 on page 176).
Three different analysis tools based on TVI data are available:
• ’Vpeak measurement’ on page 171, enables the display 
of a tissue velocity trace for a selected region of a 
previously scored segment through the entire heart cycle. 
In addition Vpeak is color-coded on the 2D image. From the 
velocity trace, the user can estimate the peak systolic 
velocity (see reference 1 on page 176).
This tool is available in views from peak levels only and 
only when a segment has been scored in one of these 
views.
• ’Tissue Tracking’ on page 175, enables visualization of 
the systolic contraction of the heart by color-coding the 
myocardial displacement through the systole.
• ’Quantitative analysis’ on page 176, enables further 
quantitative analysis based on multiple tissue velocity 
traces.
The quantitative analysis is described in Chapter 7, 
’Quantitative Analysis’ on page 233. 
						

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Accessing QTVI Stress analysis tools
The three QTVI Stress analysis tools are entered by pressing a 
dedicated button on the scoring diagram (see Figure 4-11) of 
the selected view. Only views with TVI data acquired will 
display QTVI Stress tools buttons on the respective diagrams.
 Figure 4-11: QTVI Stress tools buttons
Vpeak measurement
This tool enables the user to generate a tissue velocity profile 
for a given wall segment through the entire heart cycle and 
display color-coded Vpeak in tissue. 
From the velocity trace, the user can determine whether the 
systolic Vpeak is over or under a clinically determined velocity 
threshold (see reference 1 on page 176) to confirm the wall 
motion scoring.
1. Vpeak measurement (V-peak measurement is 
displayed in views from peak levels and only 
after scoring.)2. Tissue Tracking
3. Quantitative analysis 
						

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To display a Vpeak measurement
1. Perform segment scoring as described on page 165.
When performing scoring i a view from a peak level, the 
Vpeak measurement button (V) is displayed in the 
corresponding diagram.
2. In the Scoring diagram, press V.
The trackball cursor is changed to sampling area and the 
scored peak views are updated showing:
•  A diagram with the current segment highlighted (scoring 
bullet with a ring) and the segments velocity cutoff (see 
Figure 4-12). 
See page 174 for 
further information 
on Vpeak measure-
ment interpreta-
tion.•  Color-coded velocity in tissue. The color-coding 
convention is as follow:
- Green: Velocities above threshold value + 5%
- Ye ll o w: Velocities near threshold (+/- 5% interval)
- White: Velocities below threshold value - 5%
•  A result window to display tissue velocity profile, shown 
when moving the sampling area in the view.
3. In the 2D sector, trackball the sampling point over the wall 
area corresponding to the current segment (shown as the 
highlighted segment in the diagram).
A tissue velocity profile for the actual segment is generated 
in the Result window (see Figure 4-12).
4. Use 
SEGMENT SELECT assignable to analyze the other 
segments in the peak view,
Or
Select another scoring bullet in the diagram in one of the 
peak views.
Turn-off the Vpeak measurement tool
1. Trackball to one of the V button in the peak view scoring 
diagrams.
2. press 
SELECT in the trackball area.
CAUTIONQTVI Stress can be used only in conjunction with wall motion 
scoring analysis, as a guiding tool.
When activating QTVI Stress, the measurement applies only to 
the currently highlighted segment for the current level and 
projection view. 
						

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 Figure 4-12: Vpeak QTVI Stress display
1. Threshold for current segment (green)
2. Sampling point
3. Current segment
4. Vpeak threshold for current segment5. Color-coded tissue velocity:
6. Result window with tissue velocity profile
Color-coding (velocity thresholds and tissue):
• Green: velocities above threshold value
• Yellow: velocities near threshold (0 to -10% interval)
• White: velocities below threshold value - 10% 
						

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V-peak measurement interpretation
The systolic Vpeak in the tissue velocity profile is automatically 
detected and highlighted by a vertical bar (see Figure 4-12). 
The automatically detected Vpeak should be visually verified by 
the user. In addition Vpeak thresholds are displayed as color-
coded horizontal lines (see Figure 4-12). These thresholds 
represent statistical guideline values for peak velocity at peak 
stress level (Dobutamine stress procedure) for the three apical 
views. Only threshold values for basal and mid-segments for 
each apical view are defined (see reference 1 on page 176). 
The result is highlighted by a color-coding of the thresholds 
lines, the color-coding in the 2D image and the scoring bullet 
(see Figure 4-12). 
						

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Tissue Tracking
Tissue Tracking calculates and color-codes the displacement in 
tissue over a given time interval. The displacement is found as 
the time integral (sum) of the tissue velocities during the given 
time interval. The color-coded displacements calculated in the 
myocardium are displayed as color overlay in the respective 
acquisition window.
By studying the color patterns generated in the different 
segments, the user can confirm the standard segmental wall 
motion scoring at peak levels.
To display Tissue Tracking
1. Trackball to a loop with TVI data (usually an apical view at 
peak level).
2. Press 
SELECT on the control panel.
3. Trackball to the corresponding Wall segment diagram.
4. Press T on the Wall segment diagram field (see Figure 4-
11, page 171).
The Tissue Tracking color overlay is displayed in the 
Acquisition window.
 Figure 4-13: Tissue Tracking display 
						

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Quantitative analysis
Quantitative analysis enables further analysis based on 
multiple tissue velocity traces. Quantitative analysis is 
performed using the Quantitative analysis package described 
in Chapter 7, ’Quantitative Analysis’ on page 233.
To start quantitative analysis
1. Trackball to a loop with TVI data (usually an apical view at 
peak level).
2. Press 
SELECT on the control panel.
3. Trackball to the corresponding Wall segment diagram.
4. Press Q on the Wall segment diagram field to launch the 
Quantitative analysis package (see page 233).
References
1.Application of Tissue Doppler to Interpretation of 
Dubotamine Echocardiography and Comparison With 
Quantitative Coronary Angiography. Cain P, Baglin T, 
Case C, Spicer D, Short L. and Marwick T H. Am. J. Cardiol. 
2001; 87: 525-531