Aun-Yeong Chong MD, MRCP(UK), MBBS University of Ottawa Heart Institute

Transcription

1 Aun-Yeong Chong MD, MRCP(UK), MBBS University of Ottawa Heart Institute Cardiac Imaging Symposium Oct 2013

2 Invasive Coronary Artery Assessment Coronary angiography IntraVascular UltraSound (IVUS) Optical Coherence Tomography (OCT) Pressure wire We are duty bound to produce a useful study at the end because there is a risk to each procedure

3 Coronary Angiography Understand Catheter selection for adequate cannulation Transradial vs Transfemoral Proper angulation to visualise every segment in orthogonal views Complications and contraindications of angiography Measures of Epicardial vs. Microvascular Perfusion

4 Commonly used catheters. Adapted from Baim and Grossman

5 Transradial Coronary Angiography

6 Breakdown of anatomy and procedural Anatomical Findings outcome No. of Patients (n=1026) % No. of failure * (%) P value Normal (0.9) NA Types of anomaly High RA bifurcation (5.0) RA loop (40.1) < RA tortuosity (24.0) <0.001 UA anomaly NA Others (23.8) <0.001 Total aomalies (15.5) < *Percentage of failure to RA anatomical findings; Lo TSN, et al

7 Transradial catheters Tiger, Jacky, RBL, Kimny, Barbeau Why do we need dedicated catheters? Different backup Allows intubation of both vessels to avoid radial artery spasm from multiple catheter exchanges

8 Transradial Catheters

9 Radial vs Femoral

10 Coronary angiography Adapted frombaim and Grossman

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13 Risk of Stroke?

14 One size DOES NOT fit all

15 Different projections Adapted from Braunwald s

16 Different projections Adapted from Braunwald s

17 Different projections Adapted from Braunwald s

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19 Adapted from Braunwald s

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21 LIMA Adapted from Braunwald s

22 From ACC/AHA guidelines on coronary angiography

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24 TIMI Flow Grades Angiographic score Evaluation of epicardial flow into coronary vessel Not good for evaluation of microvascular reperfusion Correlation with outcomes

25 TIMI 1 Monitoring Reperfusion TIMI Grade Flow Scoring System 14 Mortality at 42 Days TIMI 0 Complete occlusion TIMI 1 Penetration of obstruction by contrast but no distal perfusion TIMI 2 Perfusion of entire artery but delayed flow TIMI 3 Full perfusion, normal flow p< TIMI 0/1 TIMI 2 TIMI 3 Flygenring BP et al. JACC 1991;17:275

26 TIMI 0 TIMI 1 TIMI 2 TIMI 3 Occlusion Penetration Slow Flow Normal Flow 9.3% P=0.003 vs TIMI 0/1 6.1% p< vs TIMI 0/1 p< vs TIMI % % Mortality % Mortality Team 2 Team 2 German GUSTO 1 GUSTO 1 TAM I 1-7 TAM I 1-7 TIM I 1,4 5,10B Team 2 Team 2 German GUSTO 1 GUSTO 1 TAM I 1-7 TAM I 1-7 TIM I 1,4 5,10B Team 2 Team 2 German GUSTO 1 GUSTO 1 TAM I 1-7 TAM I 1-7 TIM I 1,4 5,10B Sample Size of Pooled Analysis: 5,498 Gibson 1998

27 TIMI Frame Count Grading system based on number of frames for dye to travel into distal vessel Adjustment depending on coronary vessel involved Films taken at 30 frames at lower magnification Evaluation usually conducted in core lab Good evaluation of epicardial and microvascular reperfusion Correlation with adverse outcomes

28 First Frame Definition Last Frame Definition Distal Landmark RCA 1st branch off posterolateral Frame 0: Dye Touches One or No Borders LCX Frame 1: Dye Touches Both Borders & Moves Forward Frame 21: Dye first enters landmark Gibson, Circulation 1996; 93: Whale s tail or pitchfork or most distal branch LAD at apex Last branch off most distal OM LAD Normal Flow in the Absence of MI : frames

29 % Risk of Adverse Outcome TIMI Frame Count & Risk Stratification Within TIMI Flow Grades % 13.0% Grade 3 Flow 15.5% TIMI Flow Grades p = % Grade 2 Flow TIMI Frame Counts p = % 21.7% 22.2% 42.9% 0 < < < < < 100 > 100 Gibson et al, Circulation 1999; 99:

30 Comparison of the Global Corrected TIMI Frame Counts in Patients with and Without Adverse Outcomes p=0.02 p= p=0.06 p= p= p=0.01 p=0.01 p= Absent (n=963) Present (n=42) Absent (n=654) Present (n=22) Absent (n=619) Present (n=20) Absent (n=504) Present (n=98) Absent (n=331) Present (n=108) Death MI Shock EF<40% Any Event Gibson et al, JACC 1999; 34:

31 TIMI Blush Scores Measure by visualization of blush in the distal coronary bed Good evaluation of microvascular flow Require core lab confirmation Correlation with outcomes

32 Gibson et al, Circulation TIMI Myocardial Perfusion (TMP) Grades Mortality (%) TMP Grade 3 Normal ground glass appearance of blush Dye mildly persistent at end of washout p = 0.05 TMP Grade 2 TMP Grade 1 TMP Grade 0 Dye strongly persistent at end of washout Gone by next injection 4.4% Stain present Blush persists on next injection 5.1% No or minimal blush 6.2% % n = 203 n = 46 n = 79 n = 434

33 Mortality (%) Mortality (%) Risk Stratification Within TIMI Flow Grades Using The TIMI Myocardial Perfusion Grades 3.7% n = 487 n = 328 Epicardial TIMI Grade 3 Flow 0.7% n = 136 Myocardial Perfusion Grade 3 p = way p = % n = 34 Myocardial Perfusion Grade 2 5.4% n = 279 Myocardial Perfusion Grades 0/1 Epicardial TIMI Grade 2 / 1 / 0 Flow 4.7% n = 64 Myocardial Perfusion Grade % 7.5% n = 226 Myocardial Perfusion Grades 2/1/0 Gibson et al, Circulation 2000

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35 What do you actually see on coronary angiogram?

36 IVUS rationale Angiography = lumenography : 2D silhouette Significant observer variability poor correlation with post mortem studies U/S tomographic, image entire crosssection of arterial wall Delineate plaque composition Assess interventions pre/post Observe early atherosclerosis Glagovian remodeling conceals atherosclerosis

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39 Basic Principles Ultrasound will bounce off of some vascular structures and pass through others A structures acoustic impedance (density) will determine if U/S will bounce off of or pass through If U/S bounces off and returns to transducer the image will be white Very dense material (calcium) will reflect all the U/S and not allow any to pass through (acoustic shadow beyond)

40 Virtual Histology

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47 IVUS Applications Indeterminate lesions Regression progression trials Left main disease?unstable plaque and thrombi

48 IVUS Applications Pre interventional imaging aneurysms, calcium etc Optimal stent deployment Stent thrombosis/restenosis mechanisms; neointima, stent deployment, remodeling

49 IVUS Drawbacks Cost Time Safety 3 4% spasm, 0.1 1% major complications (MI, dissection, refractory spasm) in past now much better?cost effectiveness

50 IVUS

51 What is OCT(Optical Coherence Tomography)? Optical Coherence Tomography (OCT) is an optical imaging modality that uses near infrared light to create highresolution images of coronary arteries. OCT measures intensity of reflected infrared light.

52 Optical Coherence Tomography

53 Advantage of OCT Extreme Resolution: OCT provides up to 10 times greater resolution than ultrasound (4 20 µm compared to 110 µm) 1,2,3. Tissue Characterization: By analyzing information from the reflected light, OCT can display the composition of lesions. Real Time Imaging: A complete 55 mm imaging scan is performed in under 5 seconds so vessel occlusion is not required and the images are immediately available for review. OCT is not a source of ionizing radiation, such as x rays.

54 Performance Comparison, FD OCT vs IVUS C7XR IVUS Axial Resolution m m Beam Width m m Frame Rate 100 frames/s 30 frames/s Pullback Speed 20 mm/s mm/s Max. Scan Dia. 10 mm 15 mm Tissue Penetration mm 10 mm Lines per Frame

55 Normal Coronary Artery Intima Media Adventitia Data on file at LLI

56 STRUCTURE FUNCTION?Old view: Interventional cardiologists are non thinking Oculo stenotic reflex

57 A physiological approach to guide complex intervention.

58 What is FFR? Fractional Flow Reserve (FFR) is a lesion specific, physiological index determining the hemodynamic severity of intracoronary lesions. FFR can accurately identify lesions responsible for ischemia which in many cases would have been undetected or not correctly assessed by angiography or IVUS. FFR can only be measured at maximum hyperemia.

59 What is FFR? What s wrong with angio? 54-y-o man, PTCA prox LAD 8 years ago, stable angina, occluded distal LCx. 48-y-o man, aborted sudden death. No other stenosis at angio Radi Medical Systems AB Rev

60 What is FFR? What about other methods? Other testing methods such as IVUS, stress testing, echocardiography and even perfusion scanning are not as specific as FFR in determining the functional significance of a particular lesion on blood flow to the myocardium. FFR is also a cost-effective, time-efficient and practical method of assessment that can be used easily in a busy cardiac catheterization laboratory. 60

61 Equipment for FFR calculation PressureWire Hyperemia RadiAnalyzer Xpress

62 Overview PressureWire Certus 2007 Radi Medical Systems AB Rev

63 What is FFR? So how does FFR work? FFR myo = Pd/Pa at hyperemia FFR myo = 40/90 = Radi Medical Systems AB Rev

64 What is FFR? What does it mean? FFR result = 71% of normal 2007 Radi Medical Systems AB Rev

65 What is FFR? What does it mean? During conditions of maximum hyperemia, only 71% of the blood flow that should normally be able to go through this vessel is able to do so, due to this particular stenosis Radi Medical Systems AB Rev

66 What is FFR? How accurate is it? FFR < 0.75 : Sensitivity = 88% Specificity = 100% Fractional Flow Reserve Exercise Test Thallium Scan Stress Echo FFR has been validated against a gold standard of reversible ischemia, composed of all noninvasive tests Radi Medical Systems AB Rev Pijls NHJ et al. N Eng J Med. 1996;334(no26):

67 What is FFR? Let s go back to our original angiogram images. Guess the FFR in each lesion before moving on to the next slide A B 2007 Radi Medical Systems AB Rev

68 What is FFR? How did FFR change your treatment strategy? Hyperemia Hyperemia 2007 Radi Medical Systems AB Rev

69 FFR The true definition Maximum flow down a vessel in the presence of a stenosis compared to the maximum flow in the hypothetical absence of the stenosis. Pijls and De Bruyne, Coronary Pressure Kluwer Academic Publishers, Radi Medical Systems AB Rev

70 What is FFR? -detailed physiology FFR = Fractional Flow Reserve FFR = Pd myo Pa Pa Pd in the presence of maximum flow 2007 Radi Medical Systems AB Rev

71 What is FFR? -detailed physiology FFR = Fractional Flow Reserve FFR myo = Max flow in presence of a stenosis Normal maximum flow 2007 Radi Medical Systems AB Rev

72 What is FFR? -detailed physiology (flow and pressure) max ( - ) s FFR Q P = max = d Q n myo - P v R myo ( P P ) R a v myo 2007 Radi Medical Systems AB Rev

73 What is FFR? -detailed physiology At maximal hyperemia: Coronary flow pressure FFRmyo = Q Q s max n max = ( - ) P d - P v R myo ( P P ) R a v myo FFRmyo = P P d a 2007 Radi Medical Systems AB Rev

74 Normal FFR = P a P d = P a P d P FFR = d =1 =1 myo P a 2007 Radi Medical Systems AB Rev

75 FFR in the presence of a stenosis P a P d < P a P d FFR P = P myo d a < Radi Medical Systems AB Rev

76 FFR - independent of size of perfusion area FFR = 0.60 Large perfusion area Small perfusion area FFR = Radi Medical Systems AB Rev

77 FFR - independent of size of perfusion area Normal myocardium FFR = FFR = 0.80 Scar tissue Normal myocardium 2007 Radi Medical Systems AB Rev

78 FFR - independent of contribution of collaterals 100 FFR = 0.70 Poorly developed collaterals P a P d P v 2007 Radi Medical Systems AB Rev

79 FFR independent of contribution of collaterals 100 FFR = 0.85 Well developed collaterals P a P d P v 2007 Radi Medical Systems AB Rev

80 Multiple lesions

81 Fractional ractional Flow Reserve versus Angiography for Multivessel ultivessel Evaluationvaluation FRACTIONAL FLOW RESERVE versus ANGIOGRAPHY FOR GUIDING PCI IN PATIENTS WITH MULTIVESSEL CORONARY ARTERY DISEASE

82 FLOW CHART Patient with stenoses 50% in at least 2 of the 3 major epicardial vessels Indicate all stenoses 50% considered for stenting Randomization Angiography-guided PCI FFR-guided PCI Measure FFR in all indicated stenoses Stent all indicated stenoses Stent only those stenoses with FFR year follow-up

83 FAME study: Adverse Events at 1 year Events at 1 year, No (%) ANGIO-group N=496 FFR-group N=509 P-value Death, MI, CABG, or repeat-pci 91 (18.4) 67 (13.2) 0.02 Death 15 (3.0) 9 (1.8) 0.19 Death or myocardial infarction 55 (11.1) 37 (7.3) 0.04 CABG or repeat PCI 47 (9.5) 33 (6.5) 0.08 Total no. of MACE Myocardial infarction, specified All myocardial infarctions 43 (8.7) 29 (5.7) 0.07 Small periprocedural CK-MB x N Other infarctions ( late( or large ) 27 17

84 FAME study: Event-free Survival absolute difference in MACE-free survival FFR-guided Angio-guided 30 days 2.9% 90 days 3.8% 180 days 4.9% 360 days 5.3%

85 FAME study: Functional Class at 1 Year ANGIO-group N=496 FFR-group N=509 P-value Patients without event and free from angina 326 (68) 360 (73) 0.07 Patients free from angina, No. (%) 374 (78) 399 (81) 0.20 Number of anti-anginal anginal meds, No. 1.2 ± ± EQ-5D visual analogue scale 74 ± ±

86 FAME study: CONCLUSIONS (1) Routine measurement of FFR during PCI with DES in patients with multivessel disease, when compared to current angiography guided strategy reduces the rate of the composite endpoint of death, myocardial infarction, re-pci and CABG at 1 year by ~ 30% reduces mortality and myocardial infarction at 1 year by ~ 35 %

87 FAME study: CONCLUSIONS (2) Routine measurement of FFR during PCI with DES in patients with multivessel disease, when compared to current angiography guided strategy, furthermore: is cost-saving saving and does not prolong the procedure reduces the number of stents used decreases the amount of contrast agent used results in a similar, if not better, functional status

88 FAME study: CONCLUSIONS (3) Routine measurement of FFR during DES-stenting in patients with multivessel disease is superior to current angiography guided treatment. It improves outcome of PCI significantly It supports the evolving paradigm of Functionally Complete Revascularization, i.e. stenting of ischemic lesions and medical treatment of non-ischemic ones.

89 FAME 2 Patients in whom at least one stenosis was functionally significant (FFR 0.80) were randomly assigned to FFR guided PCI plus best available medical therapy or the best available medical therapy alone Primary endpoint: composite of death, MI or urgent revascularization

90 FAME 2

91 Conclusion Know your tools Know the risks Know the limitations of invasive coronary angiography Know how to overcome the limitations Can you get the information elsewhere...to finally get the correct diagnosis