STW vergadering

1
Intravascular Elastographypalpating plaques
with the finger of IVUS
C.L. de Korte1, F. Mastik1, J.A. Schaar1, M.
Sierevogel1,3, G. Pasterkamp3, P.W. Serruys1 and
A.F.W van der Steen1,2 1Erasmus University,
Thoraxcentre, Rotterdam, The Netherlands
2Interuniversity Cardiology Institute of the
Netherlands 3Experimental Cardiology Laboratory,
University Medical Center, Utrecht, The
Netherlands Supported by Netherlands
Organization for Scientific Research (NWO) and
the Dutch Technology Foundation (STW)
2
Background Vulnerable plaque
Plaque vulnerability Plaque composition

• Mechanical properties
• High strain region

3
Background Principle of elastography

• The response of tissue to mechanical excitation
  (e.g. compression) is a function of its
  mechanical properties.

Soft
Hard
uncompressed
compressed
4
IVUS elastography
IVUS at 100mmHg
strain
1
0
IVUS elastogram
IVUS at 80mmHg
5
IVUS elastography plaque characterization
strain
1
0
Picrosirius-red
Anti-CD68 antibody
Alpha-actin
Circulation 102(6) 617-623 (2000)
6
IVUS elastography vulnerable plaque detection
strain
1
0
Picrosirius-red
Anti-CD68 antibody
Alpha-actin
ACC 2002, presentation 1054-20
7
Predictive power of elastography to identify the
vulnerable plaque
Strain 1.26 Sensitivity 88 Specificity 89
ACC 2002, presentation 1054-20
8
In vivo elastography
140
120
Intra-coronary pressure mmHg
100
80
60
40
0
20
40
60
80
100
120
Frame no.
Strain
1.0
0.0
Eur Heart J 23(5) 405-413 (2002)
9
Cross-section LAD of patient with U.A.P
Strain
2.0
0.0
10
IVUS elastography before atherectomy
Strain
1.0
0.0
11
Histology atherectomy specimen
Fibrous cap tissue
Fibro-fatty core tissue
12
Echogram and elastogram obtained in vivo in
Yucatan
strain
1
0
Elastic-von Giesson
Picro-Sirius red
Acid Phosphatase
Polarized light
Circulation (2002) in press
13
Strain and plaque composition in Yucatan
Univariate ANOVA on strain Fat p0.007 MF p0.9
66
Circulation (2002) in press
14
3 Dimensional Elastography
15
Conclusion
Intravascular Ultrasound Elastography A
powerful technique to identify the vulnerable
plaque.