The document summarizes a meeting on vulnerable plaque research between UT-THI and Rice Coalition. It provides background on vulnerable plaque, describing it as dangerous forms of fat buildup in the arterial wall that can rupture or induce thrombosis. It reviews the history of research in this area dating back to the 19th century, and profiles the many contributors to the field. Emerging techniques for detecting vulnerable plaque non-invasively or invasively are also summarized, such as various imaging modalities, blood tests, and endothelial function tests.

1. First Meeting of
UT-THI and Rice Coalition
A Nano-Mega Initiative!
Friday, June 07, 2002
Denton A. Cooley Building
Texas Medical Center
Houston, Texas

2. How the World Dies Today?

6. Atherosclerotic Diseases Are Not
Diseases of Affluence!
• Only 2.7 millions of 6.3 million of
who died by IHD were in the
developed country.
• Cerebrovascular disease (stroke)
killed 4.4 million people, of whom
only 1.4 million were in the
developed world.

7. Leading cause of death in the
United States since the beginning
of the 20th
century?
Except for one year (1924)!

8. Fatal Heart
Attack!

9. What causesheart attack?

10. Vulnerable
Plaque
Theshort answer is:

11. What is
vulnerable plaque?

12. Dangerous forms of fat
buildup (atherosclerotic
plaques) in the arterial
wall that can rupture or
induce thrombosis and
lead to critical disruption
of blood flow.
Theshort answer is:

13. VulnerablePlaque Ruptured Plaque

16. Everybody has atherosclerosis, the question is who has vulnerable plaque
Sudden Cardiac Death
Acute MI
Vulnerable
Plaque(s)

17. Vulnerable Plaque and Vulnerable
Patient, The Challenge of
Cardiovascular Medicine in 21st
Century
An introductory tutorial from
The Center for Vulnerable Plaque Research
University of Texas Houston and
Texas Heart Institute

18. What Do We Know About
Vulnerable Plaque?
Center for Vulnerable Plaque Research
University of Texas at Houston
Texas Heart Institute
October 2001
Morteza Naghavi, MD
Mohammad Madjid, MD Silvio Litovsky, MD AlirezaZarrabi, MD
Maziar Azadpour, MD ParsaMirhaji, MD CorneliusNwora, MD
Ward Casscells, MD James Willerson, MD

19. Salute to Pioneers

20. First studies on inflammation of vessels, particularly phlebitis, Started at
a time when Cruveilhier2had just stated: La phlebite domine toute la
pathologie.3 First a great number of preparatory studies on fibrin,
leukocytes, meta-morphosis of blood, published separately. …
Rudolf Virchow 1821-1902
The Father of
Cellular
Pathology
Virchow appreciates prior works.
Virchow presented hisinflammatory theory. Heutilized thenameof "endarteritisdeformans." By thishe
meant that theatheromawasaproduct of an inflammatory processwithin theintimawith thefibrous
thickening evolved asaconsequenceof areactivefibrosisinduced by proliferating connectivetissuecells
within theintima.

21. Olcott 1931 “plaque rupture”
Leary 1934 “rupture of atheromatous abscess”
Wartman 1938 “rupture-induced occlusion”
Horn 1940 “plaque fissure”
Helpern 1957 “plaque erosion”
Crawford 1961 “plaque thrombosis”
Gore 1963 “plaque ulceration”
Friedman 1964 “macrophage accumulation”
Byers 1964 “thrombogenic gruel”
Chapman 1966 “plaque rupture”
Plaque Fissure in Human Coronary Thrombosis (Abstract) Fed. Proc. 1964, 23, 443
Paris Constantinidis
“Thedestruction of thehyalinized wall separating lumen from theatheromawas
almost alwaysobserved to bepreceded by or associated with itsinvasion by
lipid containing macrophages.” Friedman and van den
Bovenkamp 1965
Unheralded Pioneers

22. N Engl J Med 1999
“Atherosclerosis; an
inflammatory disease”
Ross R.
Russell Ross
Atherosclerosis; arterial “Response to Injury”
N Engl J Med 1976 Aug 12;295(7):369-77
The pathogenesis of atherosclerosis (first
of two parts).
Ross R, Glomset JA.

23. James T. Willerson 1981
N Engl J Med 1981 Mar 19;304(12):685-91
Plaque Thrombosis

24. Erling Falk Michael Davies
Autopsy Series
Thin Fibrous Cap + Large Lipid Core + Dense Macrophage
A culprit ruptured plaque
1981-1990

25. PlaqueEruption (Volcano!)

26. Seymour Glagov
Compensatory Enlargement
of Human Atherosclerotic Coronary
Arteries N Engl J Med 1987 May
28;316(22):1371-5
<50%
stenosis
Luminal area is not endangered until more than 40% of
internal elastic lamina is destructed and occupied by plaque
Coronary artery disease is a disease of arterial wall
disease not lumen.
PositiveRemodeling
<80%
stenosis

27. Angiographic progression of coronary
artery disease and the development of
myocardial infarction.
Ambrose JA, Tannenbaum MA, Alexopoulos D, Hjemdahl-Monsen CE, Leavy J, Weiss M, Borrico S, Gorlin R, Fuster V.
Department of Medicine, New York Cardiac Center, Mount Sinai Medical Center, New York 10029.
Simultaneously, Little et al, Haft et al reported that majority of culprit
lesions are found on previously non-critical stenosis plaques.
Conclusion:
“Myocardial infarction frequently develops from non-severe lesions.”
J Am Coll Cardiol 1988 Jul;12(1):56-62
Ambrose, Fuster, and colleagues
Angiographically Invisible Plaques

28. Falk E., Shak P.K., Fuster V. Circulation 1995
Non-stenotic (<75%) plaques cause about 80% of deadly MI

29. Macrophage-
driven MMPs
soften plaquecap
and prompt it to
rupture
P.K. Shah
Peter Libby
Thefateof atherosclerosisand
itsthrombotic complication are
governed by immunesystem.
Goran Hansson
and others
Allard van der
Wal
and others

30. •Eroded Plaque
Rupture-prone
plaques are not the
only type of
vulnerable plaque
•Calcium Nodule
van der Wal - Netherlands
Renu Virmani -USA
Thiene - Italy
Kolodgie F., Burk A.P., Farb A., and Virmani R.

31. Muller JE, Abela GS, Nesto RW, Tofler GH.
Triggers, acute risk factors and vulnerable plaques:
the lexicon of a new frontier.
J Am Coll Cardiol. 1994 Mar 1;23(3):809-13
James E. Muller 1994
Muller coined the term of “Vulnerable” Plaque
Muller likened Vulnerable Plaques to American nuclear missiles stored underground in
Nevada desert where they could be vulnerable to Russians’ long-range missile attack!

32. “Who is Who”
on
www.VP.org
Thefield of vulnerableplaqueisbest owed to
many known and unknown scientistswho have
worked hard to shed light on our way to prevent
and eradicateheart attacksin thefuture.
To seeamorecompletelist pleasevisit:

33. Natural History of
Vulnerable Plaques
Illustrated:

34. ~70%
Percent of stenosis
Frequency of plaques
“Risk” per each plaque
Culprit Risk per
each type of
Vulnerable Plaque
(Log)
Culprit lesions found
in autopsy series of
acute MI
Different Types
of Plaque
Vulnerable to
Thrombosis
All
Male
Female
~10% <5% ~20%
50%
Angiography
~80% <5% ~20%
~55% ~20%
<5%
<5% ~20%
Rupture Prone Eroded Calcified NoduleHemorrhage
Positive Remodeling
Fissured /Healed
Natural History
of Vulnerable
Atherosclerotic
Plaques

35. Ruptured Plaques (~70%)
1. Stenotic (~20%)
2. Non-stenotic (~50%)
Non-ruptured Plaques (~
30%)
1. Erosion (~20%)
2. Calcified Nodule (~5%)
Plaque Pathology Responsible for Coronary Thrombotic Death
In summary:

36. Rupture-Prone Plaque
Vulnerable Plaque Naghavi et al, Cur Ath Rep 2001
Macrophage
Necrotic lipid
core
Thin fibrouscap

37. Eroded Plaque
Vulnerable Plaque Naghavi et al, Cur Ath Rep 2001
Endothelial
denudation
Proteoglycans

38. Fissured / Healed Plaque
Vulnerable Plaque Naghavi et al, Cur Ath Rep 2001
Mural thrombi
Wounded
plaque

39. Intra-Plaque Hemorrhage with Intact Cap
Vulnerable Plaque Naghavi et al, Cur Ath Rep 2001
Leaking
angiogenesisor
ruptureof vasa
vaserum

40. Different Types of Vulnerable Plaques
Major Underlying Cause of Acute Coronary Events
Normal
Rupture-prone
Fissured Eroded
Critical Stenosis Hemorrhage
Naghavi et al, Cur Ath Rep 2001

41. Emerging
Techniques for
Detection of
Vulnerable Plaque

42. Emerging Diagnostic Techniques
A. Invasive Techniques
Angioscopy
IntravascularUltrasound (IVUS)
IntravascularThermography
IntravascularOptical Coherence Tomography (OCT)
IntravascularElastography
Intravascularand Transesophageal MRI
IntravascularNuclearImaging
IntravascularElectrical Impedance Imaging
IntravascularTissue Doppler
IntravascularShearStress Imaging
Intravascular(Photonic) Spectroscopy

43. - Raman Spectroscopy
- Near-Infrared Diffuse Reflectance Spectroscopy
-Fibrousis and lipid measurement
-pH and lactate measurement
- Fluorescence Emission Spectroscopy
- Spectroscopy with contrast media
… Invasive Techniques
Intravascular (Photonic) Spectroscopy
Intra-coronary assessment of endothelial function
Intra-coronary measurement of MMPs and cytokines

44. Emerging Diagnostic Techniques
B. Non-Invasive Techniques:
A. MRI
1- MRI without contrast media
2- MRI with contrast media: Gadolinium-DPTA
2- MR Imaging of Inflammation: Super Paramagnetic
Iron Oxide (SPIO and USPIO)
3- MR Imaging of Thrombosis using monoclonal Ab
B. Electron Beam Tomography (EBT)
C. Multi-Slice Fast Spiral / Helical Computed Tomography
D. Nuclear Imaging (18-FDG, MCP-1, Annexin V, CD40)

45. Emerging Diagnostic Techniques
C. Blood Tests / Serum Markers
- CRP
- ICAM-1, VCAM, p-Selectin, sCD40-L
- Proinflamatory cytokines
- Lp-PLA2
- Ox-LDL Ab
- PAPP-A
D. Endothelial Function Test
-Intra coronary acethylcholine test
-Noninvasive flow mediated dilatation of
brachial artery
- Anti-body against endothelial cells

46. Angioscopy
Advantages:
Intuitive (anatomic)
Simple (easy to understand)
Disadvantages:
Visualizes only the surface of the plaque
Requires a proximal occluding balloon
The spatial resolution is limited
Glistening
yellow plaque
Uchida et al, Japan

47. Intravascular Ultrasound (IVUS):
Advantage:
Reveals the morphology
of the plaque
Differs between soft
(hypo-echoic) and Hard
(hyper-echoic) plaques
Disadvantages:
Doesn’t give information about plaque
inflammation
Low spatial resolution (~ 200 µm)
Nissen, Yock, and
Fitzgerald

48. Optical Coherence Tomography (OCT)
Advantage:
Very high-resolution
Disadvantages:
Needs continuous saline wash / proximal
occlusion
Limited penetration
Does not give information
about plaque inflammation
Light Lab Inc.Mark Brezinski, James Fujimoto, Eric Swanson

49. Intravascular Thermography
Advantages:
Simplicity in theory; hot plaque
Gives information about plaque
inflammation
Disadvantages:
Plaque temperature is affected
by blood flow
Volcano Therapeutics Inc.

50. Casscells W, et al.
Thermal detection of cellular infiltrates in living atherosclerotic
plaques: possible implications for plaque rupture and thrombosis.
Lancet. 1996 May 25;347(9013):1447-51.
Vulnerable plaques are hot and acidic!
Ward Casscells and James Willerson showed ex-vivo that human
carotid atherosclerotic plaques have temperature heterogeneity
and plaques with thinner cap and higher macrophage infiltration
give off more heat. Two years later Morteza Naghavi invented
Thermosensor Basket catheter and showed invivo temperature
heterogeneity in Hypercholestrolemic Dogs and Watanabe
Rabbits. Coincidentally Stefanadis et al in 1999 confirmed
significant temperature heterogeneity invivo in patients with
unstable angina and acute MI.
Stefanadis C, et al.
Thermal heterogeneity within human atherosclerotic coronary arteries detected in
vivo: A new method of detection by application of a special thermography catheter.
Circulation. 1999 Apr 20;99(15):1965-71.

51. Photonic Spectroscopy
Advantage:
 Chemical compounds
Disadvantage:
Based on statistical analysis and
calibration is always an issue
S/N is a serious problem
Still not proven to be able to distinguish
vulnerable plaques from stable ones
Near Infrared Reflectance Spectroscopy
InfraReDx Inc.
NIR Spectroscopy
Robert Lodder, James Muller, and Pedro Moreno

52. Intravascular Elastography
Advantages:
Provides novel information, showing stiffness
Small added cost to IVUS
Disadvantage:
Does not give any chemical – compositional data,
nor shows inflammation
de Korte et al. Thorax Center, Erasmus University Rotterdam

53. Intravascular Nuclear Imaging
Immuno-scintigraphy
Advantage:
One may use radio-labeled antibodies to detect
specific antigens in plaque like MCP-1
Disadvantages:
Radiation and safety problems
Poor resolution and flow artifacts
Lack of specificity
ImetrX Inc.William Strauss and Vartan Ghazarossian

54. Magnetic Resonance Imaging
Plaque Characterization and Angiography
Advantages:
Lack of ionizing radiation
Non-invasive
Provides enormous information about flow as
well as plaque
Enhancement by contrast agents and NMR
spectroscopy
Disadvantages:
Ineligibility of patients with metal prostheses
High cost
Longer time for adoption by cardiologists

55. Human Carotid
Plaque
CCA
Carotid bifurcation
ICA stenosis & plaque
Courtesy of
Dr. Chun Yuan
University of Washington
Seattle

56. Human Carotid Plaque
Courtesy of
Dr. Chun Yuan
University of Washington

57. Fuster and Fayad and colleagues reinforced earlier MRI investigation of plaque for invivo
non-invasive detection of vulnerable plaque with large lipid pool and thin fibrous caps.

58. Noninvasive
Coronary Vessel
Wall and Plaque
Imaging With
Magnetic
Resonance
Imaging
René M. Botnar; Matthias Stuber; Kraig V. Kissinger; Won Y. Kim; Elmar Spuentrup; Warren J. Manning.
Circulation. 2000;102:2582

59. Intravascular MRI
Advantages:
Lack of ionizing
radiation
High resolution
Potential for NMR spectroscopy
Disadvantages:
Invasive and slower than fluoroscopy
Needs open/short bore high field magnet
Longer time for adoption by cardiologists
Surgi-Vision Inc.Ergin Atalar
IVUS

60. Coronary Calcium Imaging
EBT and MSCT
Advantages:
Quick and easy
Provide information about total
burden of atherosclerosis
Disadvantages:
Cannot distinguish vulnerable from stable plaque
(poor plaque characterization)
Inadequate specificity, may not accurately
predict near future event
May not be suitable for monitoring treatment
Calcium Score
Imatron Inc.Rumberger, Aard, Raggi, and others

61. Race for Non-Invasive Coronary
Angiography
• Multi-Slice Fast Computed
Tomography
(MSCT)
• Magnetic Resonance
Angiography
(MRA)

62. Plaque Morphology
vs.
Plaque Activity
Why do we need both?

63. Morphology vs. Activity Imaging
Inactive and
non-inflamed
plaque
Active and
inflamed
plaque
Appear Similar in
IVUS OCT MRI
w/o CM
Morphology
Show Different
Activity
Thermography, Spectroscopy,
immunoscientigraphy, MRI with
targeted contrast media…

64. 2001 2050
Genomic
Proteomic
2010 2020 2030 2040
VP Treatment
Home-based VP
Screening Test
Heart Attack
Eradicated
Annual
Death of MI
<10,000
Cloning Heart
VP Rx as OTC or
Vaccine?
Eradication of Heart Attack
VP Detection
Mission:

65. Center for Vulnerable Plaque Research
Ongoing Projects
Non-invasive Invasive
Diagnostic • MRI SPIO
• CT Detection
of Inflammation
• NanoScan
• MR Guide Wire
& Catheter
• Intravascular
Magnetometer
Therapy • Coronary
Dialysis
• Vaccine

66. Association for Eradication of Heart Attack
www.VP.org