PowerPoint-Pr

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The InGenious HyperCare European Network
Excellence in phenotyping Assessment of left
ventricular function
Tatiana Kuznetsova University of Leuven, Belgium
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Outline

• Systolic function
• Diastolic function
• Echocardiographic protocol (JRP A3)

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Systolic 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)

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Components of regional function

• Radial function
• Longitudinal
• Circumferential

Without the longitudinal component, sarcomere
shortening would lead to an
EF lt 30.
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Tissue 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).

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Off-line analysis
Strain
Strain rate
AVC
MVO
Time integration
AVC
MVO
Basal segments of inferior and infero-lateral
walls
Peak systolic SR
End-systolic S
SPEQLE Software Package for Echocardiographic
Quantification, Leuven version 4.06
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Inter-observer differences in percent versus
average of two readings
Mean of 2 readings
Bland and Altman, 1986
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Longitudinal S and SR by RWT
Mean values are adjusted P ?0.05 P?0.001
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Regional LV geometry

• Wall stress related to
• Pressure ? ? s ?
• Shape, cavity size ? ? s ?
• Wall thickness ? ? s ?

s P x R / 2WT
Since R curvature is larger in longitudinal
direction, the stress on longitudinal fibres is
higher, they show decreased deformation first.
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Systolic 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.

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Diastolic 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

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Transmitral blood flow vs pulsed Tissue Doppler
Imaging
A
E
Aa
Ea
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Inter-observer differences in percent versus
average of two readings
Mean of 2 readings
Bland and Altman, 1986
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Determinants 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 (Plt0.0001
  for all) were
• Ea 0.43
• Aa 0.41
• Ea/Aa 0.46.

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Echocardiographic performance protocol

• 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)

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Methods to limit echocardiographic measurement
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
2004171086-1119
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Methods to limit echocardiographic measurement
variability

• Reading off-line strategies
• Batch read when possible to minimize systematic
  temporal drifts
• Average multiple beats (minimum of 3)
• Single reader preferable.
• Establish acquisition and reader variability
• Test-retest of small sample of participants, ie,
  same participant repeated over small interval,
  same machine, same sonographer, same reader
• Blind duplicates for inter-reader and
  intra-reader variability assessment.

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Echo-centers
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