N. Duchateau, M. De Craene, G. Piella, C. Hoogendoorn, E. Silva, A. Doltra, L. Mont, M.A. Castel, J. Brugada, M. Sitges, and A.F. Frangi. Atlas-based Quantification of myocardial motion abnormalities: Added-value for the understanding of CRT outcome?. In Statistical Atlases and Computational Models of the Heart (STACOM). MICCAI Workshop., 2010. http://www.dtic.upf.edu/~mde/pdf/stacom10/DuchateauStacom10.pdf

1. Atlas-based Quantication of Myocardial Motion
Abnormalities: Added-value for the
Understanding of CRT Outcome?
STACOM-CESC Workshop, MICCAI 2010
Beijing– 20/09/2010

2. Atlas-based quantification of motion abnormalities
Atlas average
variance
Radial velocity
(mm/s)
Long. velocity
(mm/s)
Healthy subjects
1a

3. Atlas-based quantification of motion abnormalities
Atlas
Radial velocity
(mm/s)
Long. velocity
(mm/s)
Healthy subjects
Patient to study
p-value (log scale)
d = ???
1b

4. Contributions
 New quantitative indexes
[quantification of motion abnormalities]
 Statistical atlas
 Automatic
 Reproducible
 Added-value for clinical studies
 Accurate, automatic
 Generic methods applicable to almost any
 imaging modality
 studied parameter and mechanism
In this work:
Mechanisms involved in CRT response
Quantification before and after the therapy
2

5. Why quantifying abnormalities? CRT context
 Lack of reproducibility in large scale studies [1]
 Is there a “universal” index? [2,3,4]
 Changing the strategy?
Patient classification into specific etiologies of HF [5]
 Correction of specific mechanisms of dyssynchrony conditions response
 Predicitive value of specific classes
• Septal flash [5]
• Septal rebound stretch [6]
• Apical transverse motion [7]
Need to accurately characterize these patterns
[1] Stellbrink et al. , EHJ Suppl. 2004 [5] Parsai et al., EHJ 2009
[2] Chung et al. , Circulation 2008 [6] De Boeck et al., EJHF 2009
[3] Fornwalt et al. , JASE 2009 [7] Voigt et al., EHJ 2009
[4] Voigt, EHJ 2009
3

6. What is a Fig.3: Septal flash mechanism
“septal flash” ? Parsai, Bijnens et al., EHJ 2009
Healthy volunteer CRT candidate with SF
4

7. Pre-CRT Follow-up (6 months)
Effect of CRT
on septal flash
3
5

8. Pre-CRT Follow-up (6 months)
Effect of CRT
on septal flash
Pre-CRT
3
5

9. Pre-CRT Follow-up (6 months)
Effect of CRT
on septal flash
Follow-up
Pre-CRT (6 months)
3
5

10. Plan
 Atlas pipeline
 Relevance of the atlas population
 Clinical outcome after CRT

11. Construction of an atlas of “normality”[9]
[9] Duchateau et al. , MICCAI 2009
Registration-based tracking
Spatio- Atlas of
temporal
normalization
“normality”
Healthy
subjects Group statistics:
average, covariance, …
Myocardial
velocities
8a

12. Construction of an atlas of “normality”[9]
[9] Duchateau et al. , MICCAI 2009
Registration-based tracking
Spatio- Atlas of
temporal
normalization
“normality”
Healthy
subjects Group statistics:
average, covariance, …
Temporal normalization
Inital ECG Normalized timescale
8b

13. Construction of an atlas of “normality”[9]
[9] Duchateau et al. , MICCAI 2009
Registration-based tracking
Spatio- Atlas of
temporal
normalization
“normality”
Healthy
subjects Group statistics:
average, covariance, …
Spatial reorientation
8c

14. Statistical distance to “normality”
Population
of CRT
candidates
Atlas of
“normality”
Healthy
subjects
Statistical distance = p-value
associated to Mahalanobis distance
d = ??? LOW p-value = HIGH abnormality
9

15. Plan
 Atlas pipeline
 Relevance of the atlas population
 Clinical outcome after CRT

16. Data available
2D echo, 4-chamber view
21 Healthy volunteers 88 candidates OFF / ON / FU (11+/- 2 months)
EF < 35%, QRS duration > 120ms, and (or) NYHA class III-IV
60 frames/s 60 frames/s
0.24 x 0.24 mm2 0.24 x 0.24 mm2
CRT response:
Clinical
6min walking test increase ≥ 10%
Echocardiographic
LV end-systolic volume reduction ≥ 15%
or NYHA class reduction ≥ 1 point
11

17. Is the atlas representative of “normality”?
• Non-dilated hearts
• No antecedent of cardiac dysfunction
• Normal baseline characteristics
• Young (30 +/- 5)
How many subjects?
13

18. Is the atlas representative of “normality”?
• Non-dilated hearts
• No antecedent of cardiac dysfunction
• Normal baseline characteristics
• Young (30±5)
How many subjects?
Statistical distribution assumption
Statistical distance = p-value Gaussianity tests:
Shapiro-Wilk (SW) and Lilliefors (LF)
associated to Mahalanobis distance
d = ???
14

19. Plan
 Atlas pipeline
 Relevance of the atlas population
 Clinical outcome after CRT

20. Data representation
Inward Outward
Local maps at fixed time t
Temporal evolution at a fixed anatomical point
p-value
(log scale) p-value (log scale)
Red = large abnormality
10a

21. Data representation
Inward Outward
Time
Spatiotemporal maps of abnormality p-value
Apex (log scale)
Base
IVC Systole Diastole
Blue = Inward (vp<0)
Red = Outward (vp>0)
10b

22. Spatiotemporal quantification of abnormalities
Local p-value * sign of
OFF radial velocity
(log scale)
CRT #9
Septal flash
Follow-up
???
CRT #8
Septal flash
CRT #12
Left-right
interaction
IVC Systole Diastole
Blue = Inward (vp<0)
Red = Outward (vp>0)
15a

23. Spatiotemporal quantification of abnormalities
Local p-value * sign of
radial velocity
OFF Follow-up (log scale)
CRT #9
Septal flash
CRT #8
Septal flash
CRT #12
Left-right
interaction
IVC Systole Diastole
Blue = Inward (vp<0)
Red = Outward (vp>0)
15b

24. Reduction of specific abnormalities (SF)
Correction of SF = High predictive value
p-value
(log scale)
17

25. Conclusions
 Added-value for clinical studies
 Accurate, automatic
 Information still available at every location (x,t) [not heart segments only]
 Generic methods applicable to almost any
 imaging modality
 studied parameter and mechanism
 Clinical conclusions
[5] Parsai et al., EHJ 2009
Similar observations than in previous clinical studies [5,6] [6] Parsai et al., EHJ 2009
 Observation of global abnormalities leads to limited conclusions
 Correction of specific abnormalities (e.g. SF) = high predictor of
response
 Further work = extension to strain measurements (influence of local infarction)
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26. Acknowledgements
 CISTIB, Universitat Pompeu Fabra
 Image registration team
M. De Craene, G. Piella
 Hospital Clínic, Barcelona
E. Silva, A. Doltra, M. Sitges, B. H. Bijnens
Related works
Atlas construction:
 N. Duchateau, M. De Craene, E. Silva, M. Sitges, B. H. Bijnens, and A. F. Frangi
“Septal Flash Assessment on CRT Candidates based on Statistical Atlases of Motion”
MICCAI’09
LNCS 5762 (pp.759-766)
Quantification of CRT outcome:
 N. Duchateau, A. Doltra, E. Silva, M. De Craene, G. Piella, L. Mont, Ma A. Castel, J. Brugada, M. Sitges, and A. F. Frangi
“Added value of a statistical atlas-based quantification of motion abnormalities for the prediction of CRT response”
EuroEcho 2010
Randers – Lecture rooms – 09/12/2010
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