Computed Tomography of the Coronary Arteries

Transcription

1 Cardiology Update DAVOS 2011 Computed Tomography of the Coronary Arteries Anders Persson M.D., Ph.D Director, Assoc. Professor Center for Medical Image Science and Visualization Linköping University SWEDEN

2 CT Time Line 4 th Gen 3 rd Gen 2 nd Gen 1 st Gen MR EBCT Spiral CT MDCT Cardiac MDCT DE Cardiac MR Calcium Scoring MDCT Coronar Angiography

3 1972

4 1985

5 2006

6 2009

7 3sec.

8 0.25 sec.

9 9

10 Evolution of MDCT 1989 single slice spiral CT 1992 dual slice spiral CT 1999 four slice spiral CT 2001 eight slice spiral CT 2002 sixteen slice spiral CT 2004 sixty four slice spiral CT Dual source MDCT , 256 and 320 MDCT Dual source MDCT

11 To consider Type of scanner, MDCT 4, 16, 64, DS, 320, DS2 slice? I.v contrast Type of patient Staff Type of hospital...

12 Retrospectiv ECG Triggered Spiral

13 Prospectiv ECG Triggered Sequential Siemens

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15 High pitch 0.25 sec.

16 3D < 65 bpm 1-4 msv > 65 bpm > 3-20 msv 4D

17 CTCA as filter test symptoms age, gender stress tests 0% 100% risk of CAD no catheter indicated??? catheter indicated CT coronary angiography no catheter catheter surgery

18 Top 5 indications 1. Rule out coronary stenosis in patients with low to intermediate likelihood of CAD 2. Evaluation of suspected coronary artery anomaly 3. Resolve questions after cardiac catheter 4. Establish patency of bypass grafts 5. Preoperative evaluation, non-coronary surgery

19 Limitations of cardiac CT; high radiation dose?

20 CT Dose? Ca ALARA 100 msv

21 Limitations of cardiac CT; high radiation dose? 16-slice 6 11 msv 64-slice 9 21 msv Dual-Source msv Diagnostic Cardiac Catheter 3-23 msv # ± similar to the reference standard *Stolzmann et al. Eur Radiol 2008; 18(3): *Alkadhi et al. Eur J Radiol 2008; 68(3): # Einstein et al. Circulation 2007; 116(11):

22 Limitations of cardiac CT; high radiation dose? Alkadhi et al, Eur J Radiol 2008; 68(3):

23 Cardiac sequence technique, step-and-shoot mode <65 bpm -> 0.4 msv Joerg Hausleiter, MD; Franziska Herrmann, MD; Stefan Martinoff, MD, German Heart Center, Munich, Germany

24 Cardiac CT Dose msv Gating - kv

25 0.6 msv 0.6 sec.

26 0.7 msv 0.6 sec.

27 Multi-center multi-vendor trial, 50 sites, 1965 coronary CTAs Mean radiation dose: 5.7 msv 36.5 msv Definition Flash: ~ 1 msv Source: 1: Hausleiter et al, JAMA 2009 Feb 4;301(5):500-7

28 SCAAR annual report 2009

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31 2D?, 3D?, MPR?, cmpr?, MIP?, 4D?, 5D

32 CT heart

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36 Diagnostic performance of CT Recent CT scanner generations: n notevaluative sensitivity specificity PPV NPV all 4-slice CT % 79% 94% 52% 96% all 16-slice CT % 88% 97% 70% 97% alle 64-slice CT % 89% 97% 76% 99% Dual Source CT scanner: Author year n notevaluative sensitivity specificity PPV NPV Scheffel % 96% 98% 86% 99% Leber % 90% 98% 91% 99% all DSCT % 93% 97% 85% 99%

37 Diagnostic performance of CT Study TP FP FN TN Sensitivity Specificity Sensitivity Specificity Alkadhi HP 2010 Alkadhi SAS 2010 de Graaf 2010 Dewey 2009 Labounty ns 2010 Labounty s 2010 Marwan 2010 Meng 2009 Rasmussen 2010 Tsiflikas 2010 van Werkhoven 2010 Weustink o 2009 Weustink s [0.73, 1.00] 0.94 [0.71, 1.00] 1.00 [0.90, 1.00] 1.00 [0.72, 1.00] 1.00 [0.83, 1.00] 1.00 [0.81, 1.00] 1.00 [0.77, 1.00] 0.98 [0.92, 1.00] 0.96 [0.87, 1.00] 0.94 [0.88, 0.98] 1.00 [0.79, 1.00] 1.00 [0.98, 1.00] 1.00 [0.96, 1.00] 0.91 [0.75, 0.98] 0.94 [0.80, 0.99] 0.88 [0.69, 0.97] 0.94 [0.73, 1.00] 0.94 [0.73, 1.00] 0.85 [0.66, 0.96] 0.85 [0.71, 0.94] 0.79 [0.58, 0.93] 0.63 [0.53, 0.72] 0.80 [0.69, 0.89] 0.89 [0.76, 0.96] 0.85 [0.76, 0.91] 0.88 [0.70, 0.98]

38 Diagnostic performance of CT

39 Strengths of CT coronary angiography fast imaging method comprehensive evaluation low risk (non invasive) stenosis assessment beyond pure luminography cross-sectional vs luminographic imaging stenosis and cause of stenosis stenosis

40 Stages of Atherosclerosis Naghavi Circulation 2003

41 Soft <50HU, Intermediate HU, Calcified >120HU

42 Today TO RULE OUT SIGNIFICANT CORONARY ARTERY DISEASE IN INTERMEDIATE RISK CHEST PAIN PATIENTS

43 Tomorrow? TO VISUALIZE MYOCARDIAL PERFUSION?

44 Soft Plaque

45 Contrast Kinetics Ischemic Myocardium Iodinated IV Contrast Mostly intravascular during early first pass circulation Time to Contrast Arrival: 3.6±2.3 vs. 11.6±3.9 secs Time to Peak Contrast: 15.9±4.9 vs. 22.0±7.3 secs Overall Peak Contrast: 125.6±33.6 vs ±24.9 Ischemic

46 SOMATOM Definition Flash Heart Perfusion

47 Cardiac Perfusion Imaging CT Early attempts at CT imaging of LV perfusion and viability Limited by experimental nature Limited by dedicated acquisition protocols Dual-energy CT for myocardial perfusion defects Delayed enhancement dual-energy CT Adenosin stress dual-energy CT

48 One stop shop? CT cor. Syst. CT perfusion. DECT Spect.. Test inj Adenosin. Tc-inj. 7 min. 4-5 min. 60 min.

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51 One stop shop? DECT

52 MRI

53 Cardiac flow patterns, healthy subject Direct Flow Retained Inflow Delayed Ejection Flow Residual Volume Ref: Eriksson J, Carlhäll CJ, Dyverfeldt P, Engvall J, Bolger AF, Ebbers T. Sem i-automatic Quantification of 4D Left Ventricular Blood Flow. J Cardiovasc Magn Reson 2010;12(1):9.

54 Turbulent flow at peak systole in the ascending aorta of a patient with a stented aortic valve prosthesis, measured by generalized phase-contrast MRI Left: 3D streamlines outline the instantaneous mean velocity field. High velocities are seen in the flow jet downstream from the coarctation. Right: A map showing turbulent kinetic energy (TKE). Ref: Dyverfeldt P, et al. J Magn Reson Imaging 2008;28:

55 Functional MRI imaging

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