tatiana kuznetsova university of leuven, belgium the ingenious hypercare european network excellence...
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Tatiana Kuznetsova
University of Leuven, Belgium
The InGenious HyperCare European Network The InGenious HyperCare European Network
Excellence in phenotyping:Excellence in phenotyping:
Assessment of left ventricular Assessment of left ventricular functionfunction
OutlineOutlineOutlineOutline
Systolic function
Diastolic function
Echocardiographic protocol (JRP A3)
LVFLVF
Systolic functionSystolic functionSystolic functionSystolic function
Conventional echocardiography enables the assessment
of LV dimensions, volumes, sphericity index, and severity
of mitral regurgitation;
HF due to systolic dysfunction is relatively easy to
diagnose by echocardiography.
(dilated left ventricle with a reduced ejection fraction)
LVFLVF
• Radial function
• Longitudinal
• Circumferential
Components of regional functionLVFLVF
Without the longitudinal component, sarcomere shortening would lead to an EF < 30%.
Tissue Doppler imagingTissue Doppler imagingTissue Doppler imagingTissue Doppler imaging
Tissue Doppler Imaging (TDI) makes it possible to
specifically evaluate the longitudinal and radial
components of regional LV systolic function.
Measurements of myocardial deformation with the
Doppler technique have been validated using
microcrystals and MRI (Urheim S, Circulation 2000;
Edvardsen T, Circulation 2002).
LVFLVF
Basal segments of inferior and infero-
lateral walls
AVC MVO
Timeintegration
Peak systolic SR End-systolic S
StrainStrain rate
AVC MVO
LVFLVF Off-line analysisOff-line analysisOff-line analysisOff-line analysis
SPEQLE: Software Package for Echocardiographic Quantification, Leuven; version 4.06
Inter-observer differences in percent Inter-observer differences in percent versus average of two readingsversus average of two readingsInter-observer differences in percent Inter-observer differences in percent versus average of two readingsversus average of two readingsLVFLVF
Bland and Altman, 1986
Mean of 2 readings
Longitudinal Strain
0.16 0.20 0.24 0.28 0.32
-20
-10
0
10
20
14.1%
-1.38%
-16.8%
%
2 o
bse
rver
s
Radial Strain
0.4 0.5 0.6 0.7 0.8 0.9 1.0
-20
-10
0
10
20
18.9%
0.97%
-17.0%
Longitudinal S and SR by RWT Longitudinal S and SR by RWT Longitudinal S and SR by RWT Longitudinal S and SR by RWT LVFLVF
Mean values are adjusted; * P 0.05 ***P0.001
Longitudinal Strain
RWT < 0.43 RWT 0.43
20
21
22
23
24
***
%
Strain Rate
RWT < 0.43 RWT 0.43
1.20
1.25
1.30
1.35
1.40
RWT < 0.43N=335
RWT 0.43N=75*1/
s
Regional LV geometry Regional LV geometry Regional LV geometry Regional LV geometry LVFLVF
Wall stress related to:
•Pressure ↑ → σ ↑
•Shape, cavity size ↑ → σ ↑
•Wall thickness ↑ → σ ↓
σ = P x R / 2WT
Since R curvature is larger in longitudinal direction, the stress on longitudinal fibres is
higher, they show decreased deformation first.
Systolic functionSystolic functionSystolic functionSystolic function
TDI, compared with conventional echocardiography, is a more
sensitive method for the detection of LV systolic dysfunction,
particularly in subjects with LV remodelling and normal EF.
Our observations underscore the importance of normal long axis
function in maintaining a coordinated ventricular contraction.
The clinical utility of strain and strain rate in risk stratification or as
therapeutic target remains to be established.
LVFLVF
Diastolic functionDiastolic functionDiastolic functionDiastolic function
About 50% of patients with new onset of HF do have a normal EF
(HF with preserved EF).
HF with preserved EF is associated with a high mortality rate,
comparable to that of patients with reduced EF.
(Bhatia R.S., N Engl J Med 2006; Bursi F., JAMA 2006)
Assessment of diastolic function requires conventional and
Tissue Doppler Imaging
LVFLVF
Transmitral blood flow vs pulsed Transmitral blood flow vs pulsed Tissue Doppler ImagingTissue Doppler Imaging Transmitral blood flow vs pulsed Transmitral blood flow vs pulsed Tissue Doppler ImagingTissue Doppler Imaging
EA
Ea Aa
LVFLVF
LVFLVF
Ea
5 10 15 20 25
-7
-5
-3
-1
1
3
5
7
5.26%
0.72%
-3.83%
%
2 o
bse
rver
s
Aa
2.5 5.0 7.5 10.0 12.5 15.0 17.5
-7
-5
-3
-1
1
3
5
7
0.26%
4.48%
-3.96%%
Mean of 2 readings
Inter-observer differences in percent Inter-observer differences in percent versus average of two readingsversus average of two readingsInter-observer differences in percent Inter-observer differences in percent versus average of two readingsversus average of two readings
Bland and Altman, 1986
Determinants of TDI velocitiesDeterminants of TDI velocitiesDeterminants of TDI velocitiesDeterminants of TDI velocities
Stepwise analysis:
Ea: age, BMI, DBP, LVMI; LV length, EF;
Aa: age, HR, DBP, LV length, EF;
Ea/Aa: age, BMI, HR, DBP.
Intrafamilial correlation coefficients (P<0.0001 for all) were:
Ea: 0.43;
Aa: 0.41;
Ea/Aa: 0.46.
LVFLVF
Echocardiographic performance protocolEchocardiographic performance protocolEchocardiographic performance protocolEchocardiographic performance protocolEchoEcho
A single observer performs all echocardiographic examinations by means of
Vivid 7 ultrasound scanner (GE Vingmed, Horten, Norway)
Standardized echocardiography scanning sequence (about 40 min,
page 76-77 MOP JRP A3)
Correct orientation of the ultrasound beam and imaging planes to LV
structure and blood flow is essential
All echocardiographic examinations in a digital format are stored on a local
network for off-line reading by two independent observers (EchoPack, GE
and SPEQLE, University of Leuven)
Methods to limit echocardiographic Methods to limit echocardiographic measurement variabilitymeasurement variabilityMethods to limit echocardiographic Methods to limit echocardiographic measurement variabilitymeasurement variability
Use echocardiography central reading laboratory:
a. Minimize number of readers,
b. Monitor reader variability,
c. Rapid communication with study sites on study quality.
Standardized “hands-on” training of sonographers onsite.
Monitoring of sonographers for technical quality; encode study
quality in database.
American Society of Echocardiography Recommendations for Use of Echocardiography in Clinical Trials. J Am Soc Echocardiogr 2004;17:1086-1119
EchoEcho
Methods to limit echocardiographic Methods to limit echocardiographic measurement variabilitymeasurement variabilityMethods to limit echocardiographic Methods to limit echocardiographic measurement variabilitymeasurement variability
Reading off-line strategies:
1. Batch read when possible to minimize systematic temporal drifts;2. Average multiple beats (minimum of 3);3. Single reader preferable.
Establish acquisition and reader variability:
1. Test-retest of small sample of participants, ie, same participant repeated over small interval, same machine, same sonographer, same reader;
2. Blind duplicates for inter-reader and intra-reader variability assessment.
EchoEcho
Katholieke Universiteit Leuven, B JA Staessen, T Kuznetsova, T Richart
Jagiellonian University Cracow, PL K Kawecka-Jaszcz, K Stolarz, M Loster
Medical University of Gdansk, PL K Narkiewicz, W Sakiewicz, A Rojek
Universitá degli Studi di Padova, I E Casiglia, V Tikhonoff
Hospital Universitari Valencia, SP E Lurbe, J Alvarez
Institute of Internal Medicine, RU Y Nikitin, S Malyutina, A Ryabikov
Echo-centersEcho-centersEcho-centersEcho-centersJRP A3JRP A3