I have no financial disclosures

Transcription

1 Manpreet Singh MD

2 I have no financial disclosures

3 Exercise Treadmill Bicycle Functional capacity assessment Well validated prognostic value Ischemic assessment ECG changes ST segments Arrhythmias Hemodynamic response to exercise Overall sensitivity 68% 60% one vessel; 71% multivessel Specificity 77%

4 Able to exercise to target heart rate 85% of maximum age-predicted heart rate Normal ECG RBBB Less than 1 mm ST depression Men?Perhaps not women decreased specificity

5 Preexcitation (WPW) Ventricular paced rhythm > 1 mm ST depression Left bundle branch block Digoxin therapy (IIb) LVH (IIb) Known CHD Unless assessing functional capacity or prognosis

6 ECG monitoring on all stress tests Imaging Modalities Nuclear Echocardiography Cardiac MR (CMR) Stress agents Exercise Dobutamine Echo, Nuclear, or CMR Vasodilators (dipyridamole, adenosine, Lexiscan) Nuclear or CMR

7 Higher sensitivity & specificity than regular stress test Nuclear (SPECT with technetium) Sensitivity 88% Specificity 77% Echocardiography Sensitivity 76% Specificity 88% PET Sensitivity 91% Specificity 82%

8 In a typical nuclear cardiac imaging exam, the physician reviews: Static Summed Perfusion Images Dynamic Gated Images Perfusion Images are viewed in three orientations: SA Short Axis VLA Vertical Long Axis HLA - Horizontal Long Axis

9 What do MPI images look like? - Summed Perfusion Images Summed images are used to assess cardiac perfusion. Rest and Stress images are compared to determine if a region of the heart is ischemic starved of oxygen In the study below, the rest image indicates normal blood flow, but the stress image indicates abnormal blood flow in the Inferior-lateral region. Stress Rest This may indicate ischemia in this region of the heart which is supplied by the LCX (left circumflex artery). There may be stenosis in that coronary artery.

10 What do MPI images look like? Gated Images SA HLA VLA Gated images are made possible by ECG-gated SPECT Physicians can now access cardiac function: Wall motion does the LV contract uniformly? Ejection Fraction does the LV pump out enough blood to the body?

11 Improved sensitivity and specificity Determine site and extent of ischemia Results reproducible Ventricular size assessment Well-validated for detection of severe CAD and for assessment of prognosis

12 Higher cost Longer time to complete Radiation Artifact due to soft tissue or diaphragmatic attenuation Low specificity in LBBB

13 Accurate assessment of disease in patients unable to exercise Relatively safe with appropriate patient selection More specific for patients with LBBB

14 Sensitivity and specificity similar to nuclear imaging Assess presence and extent of CAD Results immediately available Portable Shorter test time Lower cost compared to nuclear Can assess multiple parameters Global & regional ventricular function Chamber size Valvular function

15 Interpretation subjective and nonstandardized Interpretation difficult with resting wall motion abnormalities Nondiagnostic images due to poor acoustic windows in significant number of patients Not recommended for patients with LBBB or ventricular paced rhythm

16

17 Size of the chambers of the heart Pumping function of the heart Valve Function Volume status Other Uses: fluid in the pericardium, congenital heart diseases, blood clots or tumors within the heart

18

19

20

21 No special preparation, nor medication restrictions. Patient lies in CT scanner for about 10 minutes and must hold breath between seconds during imaging. Radiation exposure: msv (milli-sieverts) Avg. yearly natural background exposure in US: 3 msv Diagnostic cardiac catheterization: 4.5 msv Coronary Artery Calcification (CAC) Score Agatston Score Based on area and density of calcified plaques Typical report includes: Agatston score for each major coronary artery Total Agatston score for the patient Several representative images

22 In multiple studies the following definitions have been used to correlate the CAC score and the coronary plaque burden: >400 No identifiable disease Mild Disease Moderate Disease Severe Disease

23 On CT, calcium has high attenuation values very bright! LCA

24 2010 American College of Cardiology Foundation (ACCF) and the American heart Association (AHA) found that: CAC screening should not be used in asymptomatic low or high 10-year CHD risk patients according to Framingham criteria. CAC screening is useful for intermediate 10-year CHD risk (10-20%) according to Framingham criteria, or low to intermediate( 6-10%). If the CAC core is elevated (>300), start aggressive risk factor reduction. A low CAC (<100) effectively excludes obstructive CAD in outpatients with atypical chest pain There is no current evidence that treatment decisions based on CAC scores leads to outcome improvement.

25 Screening: no application Diagnosis of CAD Intermediate likelihood of disease After equivocal/discordant stress imaging Coronary anomalies Before valvular surgery Nonischemic vs. ischemic cardiomyopathy Bypass graft patency/location (images of transplanted arteries and veins are much better) Risk stratification (known CAD) After equivocal/discordant stress imaging

26 CT angiography provides high resolution imaging of the heart and give good visualization of the coronary arteries

27

28 Global cardiac function and regional wall motion abnormalities Regional perfusion Myocardial infarction Coronary MRA Viability

29 Viable myocardium may benefit from revascularization and resume normal cardiac function Function cannot be restored to nonviable tissue

30

31 Resting Ankle-Brachial Index (ABI) Exercise ABI Segmental pressure examination Pulse volume recordings These traditional tests continue to provide a simple, risk-free, and cost-effective approach to establishing the PAD diagnosis as well as to follow PAD status after procedures.

32

33 150 Brachial ABI 0.44

34 ABI will identify disease Segmental pressures yield level of disease Pressures between levels should be w/in 20 mmhg Differences mmhg considered borderline Gradient > 30 mmhg = sign. disease between segments Gradient >40 mmhg suggests occlusion Right & left extremities should be w/in 20 mmhg Large collaterals can result in normal pressures Pressures reflect functional status rather than anatomic condition

35

36 Cuffs placed around limb segments Measured amount of air added to cuff to achieve preset pressure 65 mmhg in limbs 40 mmhg in digits Record PVR over 3-4 cardiac cycles

37 Normal Moderate Severe Practical Noninvasive Vascular Diagnosis, 1982 Spectrum of extremity arterial

38

39

40 20-49% Ratio <2: % Ratio 2: % Ratio 3:1 Occlusion No flow

41 Common femoral ± 25 Superficial femoral - 90 ± 15 Popliteal - 69 ± 15 Tibial vessels - 61 ± 20

42 THANK YOU