coronary cta: the test of choice for obstructive cad
TRANSCRIPT
Coronary CTA : The Test of Choice for Obstructive CAD
LMLAD
LCxLM
LMLAD
LCx
Intramural hematoma
13.9 mm
LAD
Diag
Septals
LCxRCA
Harvey S. Hecht, MD, FACC, FSCCT Associate Director of Cardiovascular Imaging Professor of Medicine, Icahn School of Medicine at Mount
Sinai
Vessel Analysis
• CTA QCA: measure rather than eyeball
% Stenosis
1. 25-50
2. 50-75
3. > 75
Ostial LAD
62% stenosis
• Area calculation far superior to MLD: MLD has no physiologic significance except in the rare perfectly concentric lesion
Vessel Analysis
• CTA QCA: measure rather than eyeball
Ostial LAD
Obstr Reference % Stenosis
Effective diameter (mm) 3.1 5.8 46
Lumen area (mm2) 7.7 26.0 71
L Main
Calcified plaque
noncalcified plaque
lumen
L Main
MLA 4.3 mm2
L Main
noncalcified plaque
lumen
Calcified plaque
L Main
MLA 4.3 mm2 4.5 mm2
MLA 13.0mm2 3.8 mm2
47 yo asymptomatic male 2 yrs after LCx DES; ST elevation with exercise, nl LM on cath
LAD
LM
bridge
LAD
MLA 2.7 mm2 2.8 mm2
LM
LCxLAD
LCx
LM
LAD
MLA 5.5 mm2 3.6 mm2 3.3 mm2
448
-11
89
70
138
Intramural hematoma
LM/LAD
MLA 5.9 mm2 3.1 mm2 2.5 mm2
dLM oLAD pLAD
hematomahematoma hematoma
hematoma
hematoma
Stents
Normal Normal
in-stent restenosis
stent fracture
jailed branches
edge stenosis
bifurcation stents
inadequate stent expansion
Stent sizing
1% of CTA volume Failure of image acquisition Inability to selectively cannulate a native vessel or graft Severe pressure damping
Requirement for additional information Ostial disease versus spasm Course of anomalous vessels Relationship of bypass grafts to the sternum Graft morphology Chronic total occlusions
J Inv Cardiol 2008;20:1-6
Septals
Diag
RCA
LAD
LADSeptal
CTO
Diagnostic Performance and Comparative Cost-Effectiveness of Non-invasive Imaging Tests in Stable Patients
with Suspected Coronary Artery Disease: A Systematic Overview
Van Wardhuizen.Curr Cardiol Rep 2014;16:537
Diagnostic 13 studiesCost Effect 11 studies
Sens SpecCTA 83-100% 81-92%CMR 87-91% 70-84%SPECT 81-94% 48-85%PET 84-90% 81-88%SE 68-87% 72-93%
CTA best gatekeeper
CTA most cost effective
Accuracy
# Studies Sensitivity Specificity ArteriesSPECT 45 69% 79% CMR 17 84% 83% PET 7 77% 88% CTA 12 97% 93%
Diagnostic Performance of SPECT, CMR and PET for Detection of Obstructive CAD: Meta-analyses
Jaarsma JACC 2012; ;59:1719–28 von Ballmoos. Ann Int Med 2011;154:413-20
Accuracy
Comparison of Nuclear and CTA for >50% Stenosis in Individual Arteries
* Meijer et. AJR 2008; 191:1667–75
Sens Sens Spec ● * Nuclear CTA Segments 90.8% 95.7% proximal 94.2% 94.1% distal 84.8% 96.9%Vessels Lmain 85%† 100% 99.1% pLAD 81% 94.3% 93.8% pLCx 77% 85.3% 95.4% pRCA 75% 95.8% 97.7%
● Mahmarian.JACC 1990:318-29 †Berman JNC 2007;14:521-8
Accuracy
Pre-test vs Post-test Probability of CAD by SPECT MPI, 2DE and CCTA
Nuc Sens 83% Spec 77%Echo Sens 83% Spec 81%
CCTA Sn 94% Sp 89%64 slice 2005-2009
ACC/AHA/ASE 2003 Guidelines for EchocardiographyACC/AHA/ASNC 2003 Guidelines for Cardiac Radionuclide Imaging
Pre-test probability of Disease (Prevalence)
143 pts TVD: >70% 3V or >50% LM+>70% RCA
SPECT MPI for Triple Vessel Disease
Lima et al. JACC 2003;42;64-70
Perfusion Perf+ FunctionNL 18% 12%SVD 36% 28%DVD 36% 35%TVD 10% 25%MVD 46% 60%Specificity 72% 69%
Conc: MPI fails to identify 40% of high risk TVD pts
Accuracy
80/1327 pts without known CAD
LM > 50 % stenosis + >70% other V
MPI Total LM LM+LAD/LCx LM+RCA LM+3VD
NL 10% 9% 20% 9% 4%
Low risk 5% 0% 10% 5% 0%
Hi risk 85% 91% 70% 86% 96%
Berman et al. JNC 2007;14:521-528
Detection of Left Main Stenosis by SPECT Imaging
Conclusion: MPI misses 15% of the highest risk pts
Accuracy
MDCT Meta-analysis of Coronary ISR
Andreini. AJC 2010; 105:645– 655
Sens 89.7%Spec 92.2%PPV 72.5%NPV 97.4%Accuracy 91.9%Non evaluable 9.6%
18 studies 64 MDCT: 1300 pts, 2003 stents
AccuracyStents
Segmental Accuracy Prev Sens Spec PPV NPV
Bypass grafts 19% !00% 100% 100% 100%
Natives Distal runoffs 13% 95% 100% 100% 99% All grafted V 59% 100% 96% 97% 100% All nongrafted V 29% 97% 92% 83% 99%
Westinck et al.JACCImg 2009;2:816-24
Diagnostic Accuracy of CTA in CABG Patients
52 post CABG pts
AccuracyCABG
SVG-LAD
MLA 5.6 mm2 29.5 mm2
• Graft analysis
SVG-M1
MLA 16.6 mm2 2.6 mm2 12.6 mm2 6.8 mm2
Beller. Circulation 2000;101;1465-1478
Meta-analysis of 12,000 pts in 14 studies
Nuclear Stress Testing and PrognosisPrognosis
Stress Echocardiography and Prognosis
Yao et al. JACC 2003;42;1084-1090
1500 pts; 2.7+1.0 yr f/u
Nl Mild/Mod Abnl Sev Abnl
Prognosis
Meta-analysis of Prognostic Value of CTA 18 studies, 9,592 patients, median f/u 20 months
Sens .99Spec .41
Pooled negative likelihood ratio after nl CTA: .008
Hulten. JACC 2011;57:1237-47
Prognosis
Prognostic Value of CCTA during 5 Years of Follow Up Prognosis
1453 pts suspected CADMedian f/u 5.6 y; 58 hard events- death or nonfatal MI
CAD Annual EventsNormal 0.2 %Nonobstructive 0.7 %Obstructive 1.2%
CAD Improves Morise Risk ScoreNonobstructive 0.003# Abnormal segment <0.001
Hadamitsky. JACC 2012;59:A325
CAD and Adverse Events in Symptomatic Patients With 0 CAC Undergoing CTA: CONFIRM
Villines. JACC 2011;58:2533–40
10,037 symptomatic pts, 56 y, 51% 0 CAC, 2.1 y f/u
0 CACNo CAD 84%Nonobstr 13%>50% 3.5%>70% 1.4%
Events 0 CAC +Nonobstr 0.8%0 CAC + >50% 3.9%P <0.001
No mortality diff 0 CAC w/w/o obstr
Prognosis0 CAC
Age, Sex, and Angina Typicality–Based Approach for PretestProbability of Significant CAD by CTA: CONFIRM
Cheng. Circulation 2011;124
>50%DS
Men Women
Typical angina 40% 19%
Observed 29%
Predicted 86%
Atypical angina Observed 15%
Predicted 47%
All Observed 18%
Predicted 51%
14048 patients with suspected CAD Angina typicality, age, sex, for pretest likelihoods of >50% DS
PrognosisSymptoms
Stress echocardiography 0
Tc-99m tetrofosmin rest-stress (10 mCi 30 mCi) 10.6 Tc-99m sestamibi 1-day rest-stress (10 mCi 30 mCi) 12 Tc-99m sestamibi 2-day stress-rest (30 mCi 30 mCi) 17.5 TI-201 stress and reinjection (3.0 mCi 1.0 mCi) 25.1Dual-isotope (3.0 mCi Tl-201 30 mCi Tc-99m) 27.3New nuclear scanners 4-6Stress only 2-3
Retro MDCT coronary CTA (m) 9.6–15.2Retro MDCT coronary CTA (f) 13.5–21.4Retro MDCT coronary CTA (m) dose modulation 7.0-12Retro MDCT coronary CTA (f) dose modulation 9.0-14.0Pro Step & shoot 2-5Retro Iter Recon 3-6Pro Iter Recon Step & shoot 0.26-2
Cardiac catheterization 4-Hiroshima
Radiation Doses (mSv)
Thompson RC, Cullom SJ .J Nucl Cardiol 2006;13:19-23.
Radiation
“The relationship between radiation and the development of cancer is well understood: A single CT scan exposes a patient to the amount of radiation that epidemiologic evidence shows can be cancer-causing.”
We Are Giving Ourselves CancerBy RITA F. REDBERG and REBECCA SMITH-BINDMAN
New York Times Editorial JAN. 30, 2014
Radiation Dose in 256 Coronary CTA
Perisinakis. Circulation. 2010;122:2394-2402
Prospective CTA
Lung Ca RR Life attributable riskWomen 1.0032 24.9/100,000Men 1.0008 7.3/100,000
“The mean projected life attributable risks of radiation-induced cancer in a typical clinical patient cohort undergoing standard prospectively ECG-gated CCTA with a 256-slice scanner were found to inconsequentially increase the natural cancer incidence rates”
Radiation
Stress Myocardial CT Perfusion
Blankstein JACC2009;54:1072–84
Function
Author Scanner Reference N Population Se Sp
Kurata 16CT (stat) SPECT-MPI 12 Susp CAD 90 79
George 64/256CT (stat) QCA/SPECT 27 Pos SPECT 81 85
Blankstein 64DSCT (stat) QCA/SPECT 33 SPECT/ICA 93 74
Ho 128DSCT (dyn) SPECT 35 Recent MPI 83 78
Ko 64DSCT (stat) MRI 41 Known CAD 91 72
Tamarapoo 64DSCT (stat) SPECT 30 Pos SPECT 92 86
Weininger 128DSCT (dyn) MRI 20 Acute CP 93 99
Feuchtner 128DSCT (stat) MRI 30 Kwn/susp. CAD 96 95
Bamberg 128DSCT (dyn) FFR 36 Kwn/susp. CAD 93 87
Ko 320CT FFR 42 Kwn CAD 76 84
CORE320JACC 13Pooled 306 88.3 83.1
CT Perfusion: Diagnostic Performance
Validation Paradox
Echo Cath CTA
IVUSNuclearFFR
PETMRI
Functional tests (stress tests and FFR) and IVUS area criteria are used to judge the anatomic gold standard (cath) by which they were validated
The cath gold standard is flawed; does not correlate with IVUS
Outcomes may be the true gold standard: FFR
Hecht. JCCT 2009: 3, 334–339
PCI of Functionally Nonsignificant Stenosis:5-Year Follow-Up of the DEFER Study
Pijls. JACC 2007;49:2105–11)
325 pts with intermediate (50%) stenosis scheduled for PCI
n FFR PCIDEFER 91 >0.75 no PERFORM 90 >0.75 yesREFERENCE 144 <0.75 yes
Conc: No benefit for PCI when FFR>0.75
Function
FFR vs Angiography for Guiding PCI in Multivessel CAD:2-Year Follow-Up of the FAME Study
Pijls. JACC 2010;56:177–84
Death/MI PCI/CABG Death/MI/RevascAngio 12.9% 12.7% 22.4%FFR 8.4% 10.6% 17.9%P <0.02 0.30 0.08
MI RevascDeferred lesions: 0.2% 3.2%
1005 randomized multivessel CAD pts Angio guided PCI: all lesions stented FFR guided PCI: stent only if FFR< 0.80
FFR in multivessel CAD PCI with DES significantlyreduces 2 yr death/MI compared to angiography-guided PCI
Function
Non-invasive FFR (FFRCT)
50
3-D FFRCT map computed
FFRCT = 0.72(can select anypoint on model)
Computational Model based on CCTA
Calculate FFRCT
No additional imagingNo additional medications
3-D anatomic model from CCTABlood flow equations solved
on supercomputer
Blood Flow Solution
Physiologic models- Myocardial demand- Morphometry-based boundary condi-
tion- Effect of adenosine on microcircula-
tion
Case ExamplesCCTA Invasive angiographyFFRCT FFR
>50% diameter stenosis >50% diameter stenosisFFRCT 0.74 ischemia FFR 0.74 ischemia
0.74
0.85
FFR
>50% diameter stenosis FFRCT 0.85 no ischemia FFR 0.84 no ischemia>50% diameter stenosis
FFR
DISCOVER: Single center trial 103 pts
30% 40% 50% 60% 70% 80% 90% 100%30%
40%
50%
60%
70%
80%
90%
100%
Stress EchoJung, EHJ 2008
cCTAMin, JAMA 2012Koo, JACC 2011Meijboom, JACC 2008Norgaard 2013
SPECTMelikian, JACC CV Interventions 2010
Invasive AngiographyPark, JACC CV Interventions 2012Meijboom, JACC 2008
IVUSWaksman, JACC 2013
cCTA TAGYoon, JACC Imaging, 2012
FFRCTNorgaard 2013
Diagnostic performance of non-invasive imaging vs. FFR*FFR
Gold Standard
Spec
ificity
Sensitivity
NXT FFRCT
*Inclusive of all published studies comparing imaging against invasive FFR
Unsuspected Dissection and PEOther
RUL
LMLAD
LCxLM
LMLAD
LCx
Intramural hematoma
13.9 mm
LAD
Diag
Septals
LCxRCA
Harvey S. Hecht, MD, FACC, FSCCT Associate Director of Cardiovascular Imaging
Professor of Medicine, Icahn School of Medicine at Mount Sinai
Disclosure: Philips Medical Systems Consultant
Coronary Plaque Characterization by CT: Is the Stenosis Paradigm Too Simple?
CTA Characteristics of Plaques Subsequently Resulting in ACS
Motoyama, Narula. JACC 2009;54:49–57
ACS+ ACS- pPR 127 % 113 % .003PV 135 mm3 58 mm3 .001 LAP V 20 mm3 1.1mm3 .001%LAP/ 21.4% 7.7% .001 plaque area
1059 pts suspected or known CAD 27+10 mo f/u
Plaque
Impact of Coronary Plaque Composition by CTAOn Troponin Elevation After PCI in Stable Angina Pectoris
Watabe. JACC 2012;59:1881–8
T+ T- pHU 43 (27-76) 94 (65-109) <0.001RI 1.20 1.04 <0.001Spotty Ca 50% 11% <0.001
107 stable pts : 36 T 3xnl, 101 nl T post PCI
ORRI>1.05 4.54Spotty Ca 4.27
HU<55+RI>1.05+SC PPV 94%HU<55+RI<1.06, -SC NPV 90%
Plaque
CTA Plaque Characteristics and PCI Slow-Flow
Kodama. JACC Intv 2012;5:636–43
40 consecutive slow flow pts; 40 matched controls
SF NSF pCPC 63% 5% <0.001PRI 1.5 1.2 <0.001LAP 23.5 45 <0.001 (9.5-40) (29-86)
OR p CPC 79 <0.001Min HU 0.977 0.013Dyslipid 18 0.04
CPC: >180 deg of perimeter, >1/3 of plaque length
Plaque
Initiation of Aggressive Medical Therapy in Patients with 0 CAC Scores and Noncalcified Plaque.
Plaque
Ultra-aggressive Treatment of Nonobstructive Lesions Plaque
Accelerate Timing of PCIPlaque
Modify Interventions to Prevent PCI Complications Plaque
Override Fractional Flow Reserve (FFR) CriteriaPlaque
FFR 0.81
Smith. BMJ 2003;327:1459–61
We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute.
Conclusions: As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data.
CTA Functional testingAccuracy ++++ +++Prognosis ++++ +++ Plaque ++++ 0Anatomy ++++ 0Function ++++ +++Fast Dx ++++ ++Radiation + ++Safety ++++ +++Cost ++ +++Other Etiology ++++ 0
Comparison of CTA and Functional Testing
When is Coronary CT Angiography Indicated?
CTA is the best noninvasive test for the evaluation of atherosclerosis, from plaque to stenosis, from prognosis to function, and will be the gatekeeper for PCI
If you thought about doing a stress test, do a CTA instead
Congenital anomalies
Aneurysm, PE and EP evaluation: coronaries should always be done