Plaque Severity and Coronary Occlusion:

1
Plaque Severity and Coronary Occlusion Or, Why
Plaque Severity is More Important Than Stenosis
the less obstructive plaques gave risk to more
occlusions than did the severely obstructed
plaques because of their much greater
number.... Falk, Shah, Fuster Coronary Plaque
Disruption Circulation 199592pg. 658 Because
the aggregate risk of rupture associated with
many nonsignificant lesions exceeds that of the
fewer significant lesions, a myocardial
infarction will more likely originate from a
nonsignificant lesion. Kern, Meier Evaluation
of the Culprit Plaque Circulation 20011033142
2
EBT and Coronary Artery Calcium
55 year old woman with chest pain
No calcification EBT/CAC
EBA
low density plaque With stenosis
? low density plaque?
3
CAC by EBT and Atherosclerotic Plaque
Although not all plaque is visualized by EBCT and
soft plaque is currently not measured, the
greater the calcium score, the greater the
plaque burden
4
CAC by EBT vulnerable plaque vs vulnerable
patient
Risk increases as an individuals CAC score
and/or percentile rank increases Thus, although
EBCT and CAC is not able to identify the
vulnerable plaque, it CAN identify the
vulnerable patient
5
EBT and Coronary Artery Calcium

• Estimate Prognosis? YES

but does so based upon estimates of total
coronary atherosclerotic plaque burden and not on
visualization of hard vs soft plaque
6
EBT and CAC coronary remodeling and CAC
43 y/o woman FHx
Is this patient at higher risk due to
coronary artery remodeling?
CAC
7
Annualized Rates of Progression - EBT
Composite of 9 studies weighted average
n 292
Range 5-20
n 792
Range 22-52
8
The Search for the Vulnerable Patient

• EBT is the only non-invasive method visualizing
• the coronary arteries that has been shown to
• Track changes in coronary plaque in response
• to lipid lowering medications, and
• And suggest that the magnitude of serial changes
  can potentially be of value to predict the
  development of acute coronary syndromes

9
The Search for the Vulnerable Patient
Pieces of the Puzzle

• EBCT
• Calcium percentile
• Calcium serial changes
• Remodeling
• Contrast (soft plaque?)