2. INTRODUCTION
CAC Scoring
- in asymptomatic pt.
CAD burden
CV risk prediction
- in symptomatic pt.
high sensitivity and –ve predictive
value to exclude CAD.
3. ACC/AHA GUIDELINE–
CAC scoring (CACs) as a filter for coronary
angiography in atypical ACS.
CAC s –> as binary test
CAC+ve=further test considered.
CAC –ve=no further test required.
4. Recently question mark raised
- in population of high pre test risk of CAD
- incremental prognostic value of score
-significant incidence of CAD in pt. having
zero CACs.
5. AIM OF STUDY
To describe the prevalence and severity of CAD in
relation to prognosis in
- symptomatic patients
-without known CAD
- without coronary artery alcification
- undergoing CCTA
6. METHOD
The CONFIRM registry (Coronary CT Angiography Evaluation
for Clinical Outcomes: An International Multicenter)
international, multicenter, observational
registry
collecting clinical, procedural, and follow-up
data
on patients who underwent 64-detector row
CCTA between 2005 and 2009 at 12 centers in
6 countries(Canada, Germany, Italy, Korea,
Switzerland, and United States)
7. Symptomatic patients who underwent concomitant
CAC scoring and CCTA were included.
Individuals with known CAD were excluded.
CAC s with Agatston method
1 130-199 HU
2 200-299 HU
3 300-399HU
4 >400HU
8. Lesion quantification
LESION LUMINAL CLINICAL
GRADE STENOSIS SIGNIFICANCE
NONE 0%
MILD 1-49% NON
OBSTRUCTIVE
MODERA 50-69% OBSTRUCTIVE
TE
SEVERE > 70% SEVERELY
OBSTRUCTIVE
9. FOLLOW UP AND OUTCOME
END POINTS
Primary- Death due to any cause
Secondary- Consisting of
-all-cause mortality,
-nonfatal MI, and
-coronary revascularizations done
90 days after CCTA.
10. RESULTS
27125 Patients screened
10,037 Patients selected
(symptomatic, without known CAD,
undergoing CAC scoring and CCTA)
11. PROFILE OF STUDY GROUP
Mean age =57
Male =56 %
Among 10,037 pt. 51% has CAC score of 0.
- young
- female
- low CV risk
12. Among CAC score=0 group
13% have non obstructive CAD
3.5% have obstructive CAD
1.4% have severe obstructive CAD
13. In group of obstructive CAD and CACs = 0
82% have SVD
12% have DVD
6% have TVD
0.3% have LMD
14. For the detection of any stenosis> 50% on CCTA, the
presence of measurable CAC on calcium scoring
demonstrated a sensitivity of 89%, specificity of 59%,
negative predictive value of 96%, and positive
predictive value of 29%.
When using a threshold of 70% stenosis for
obstructive CAD, a CAC score> 0 demonstrated a
sensitivity, specificity, negative predictive value and
positive predictive value of 92%, 55%, 99%, and 16%,
respectively.
19. FOLLOW UP
During a median follow-up of 2.1 years,
patients with any obstructive CAD by CCTA
experienced a significantly increased rate of all-cause
mortality .
When restricted to individuals with a CAC score of 0,
there was no difference in all-cause mortality despite
the presence of non obstructive or obstructive CAD
20. FOLLOW UP FOR SECONDARY END
POINT
Among the 8,907 patients with complete follow-up for
the secondary endpoints of coronary revascularization
and MI, patients with evidence of obstructive CAD
had significantly increased rates of early coronary
revascularization, both among patients with and
without coronary artery calcification.
21. COMPARATIVE PROGNOSTIC VALUE OF CLINICAL VARIABLES, CAC
SCORING AND CCTA.
Independent predictor of adverse events
Increasing CAC scores,
The presence of nonobstructive CAD,
Any stenosis >50%, and
the number of coronary territories with 50% stenosis.
22. DISCUSSION
Absence of calcification decreases the likelihood Of
CAD ,but does not exclude it.
Rate of obstructive CAD in person with zero
calcification varies between 7 – 38%
Pt. with CACs=0 and obstructive CAD do not show
increased mortality due to predominent SVD.
23. LIMITATIONS OF STUDY
1.Definition of CAD was made using CCTA, the
possibility of false-positive and false-negative CCTA
findings exists.
2. Patients diagnosed with obstructive CAD on CCTA are
more likely to undergo PCI/CABG, especially in early
days.
3. Differences in the application of medical therapies
after CCTA were not assessed
4.Individual plaque character was not studied.
24. CONCLUSION
1.Absence of calcification decreases the likelihood Of
CAD but does not exclude it.
2. Among patients without CAC, the presence
of stenosis of > 50% is predictive of increased rates of
late coronary revascularizations and nonfatal MIs
during an intermediate-term follow-up period.
3. CAC scoring performed at the time of CCTA does not
appear to offer significant incremental prognostic
information
