Echo is Still Strong in Myocardial Viability Wook-Jin Chung, MD, PhD

Transcription

1 Echo is Still Strong in Myocardial Viability Wook-Jin Chung, MD, PhD Noninvasive CV Imaging Lab, HF & PAH Clinic Gachon University Gil Hospital Incheon, Korea

2 LV dysfunction Necrosis Ischemia Stunned Hibernating Viable?

3 Remodeling Necrotic tissue- replaced by fibrotic and scar tissue Stage I. For hours to a few days Stage 2. Three weeks Stage 3. Three or four weeks later

4 Techniques to Detect Viable Myocardium Characteristics of viable myocardium Contractile reserve Technique Dobutame Echo Dobutamine MRI Signs of viability Improved contraction during infusion of low-dose dobutamine Intact cell membrane Thallium-201 SPECT Tracer activity >50% Redistribution (>10%) Intact mitochondria Technetium-99m SPECT Tracer activity >50% Improved tracer uptake after nitrates Glucose metabolism 18F-FDG imaging Tracer activity >50% Preserved perfusion/18f- FDG uptake Schinkel AFL, et al. Heart 2005;91: Perfusion-metabolism mismatch

5 Spectrum of myocardial dysfunction in ICM Normal Repetitive stunning Hibernation Scar Peak Flow Flow reserve Resting Flow Systolic function CFR CFR CFR CFR X CR CR CR CR X PERF PERF PERF PERF X MET MET MET MET X Courtesy of DH Kim, AMC.

6 Myocardial Viability Myocardial Contrast Echo Otto. Practice of Clinical Echocardiography, 4 th ed, p54

7 Myocardial Viability Dobutamine Stress Echo Otto. Practice of Clinical Echocardiography, 4 th ed, p313

8 Comparison of the various imaging techniques for detecting Hibernating Myocardium Technique No. of studies No. of patients Mean EF (%) Sensitivity (%) Specificity (%) Dobutamine echocardiography.total Low-dose DbE High-dose DbE Myocardial contrast echocardiography. total Thallium scintigraphy. total Tl-201 rest-redistribution Tl-201 re-injection Technetium scintigraphy.total Without nitrates protocol With nitrates protocol Positron emission tomography.total Cardiovascular magnetic resonance. total Low-dose dobutamine protocol Late gadolinium-enhancement protocol Shah et al. EHJ 2013 review

9 Detection of Myocardial Viability Functional Recovery After Revascularization European Heart Journal (2010) 31,

10 Dobutamine Stress Echocardiography Detection of Mycardial Viability Stress Rest Low High Hyperkinetic Normal Worsening Ischemic Sustained Improvement Viable, patent IRA Biphasic Viable, stenosed IRA No Change Infarction

11 Abnormal segments revascularized (%) Dobutamine Stress Echocardiography Detection of Mycardial Viability Recovery No recovery Qureshi U et al, Circ 95:626, Biphasic worsening Worsening Sustained sustained No change n=43 n=8 improvement n=70 n=27

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13 Regional Wall Motion in 2D Echo Wall thickening Endocardial motion Synchronicity

14 Regional Wall Motion in 2D Echo Problems of `Eye Ball` Assessment 1. Limited temporal resolution 2. Only radial motion 3. Interobserver variability 4. Long learning curve Need Quantitative Measurements!

15 Importance of Quantification If you can t measure it, you can t manage it. Peter F. Drucker ( )

16 Quantification of Wall Motion Tissue Doppler Imaging Deformation Imaging

17 Longitudinal Myocardial Velocity Apical Mid Basal Annulus Palmes et al., J Am Soc Echocardiogr, 2001

18 The Left Ventricle is Isaac K, et al., J Am Soc Echocardiogr, % 70% of the muscle fibers are longitudinal!

19 Segmental TDI (S ) for IHD during Dobutamine Stress Echo Marwick T. Am J Cardiol 2001;87:

20 Change of S during LD-Dobutamine Stress Echocardiography c/w PET, n=36 Yuan D,,Hoffmann R. Echocardiogr 2001;18(8):

21 Change of S during LD-Dobutamine Stress Echocardiography c/w 3M F/U Echo, n=56 Schneider C,et al. Int J cardiol 2006;110: By ROC analysis, a cut-off value of 1.0 cm/s was the best parameter to differ viable from nonviable myocardium (area under the curve 0.85; p <0.01; 95% CI 0.79 to 0.90).

22 TDI Strain Differentiates Transmurality in AMI After Reperfusion Derumeaux G et al. Circulation 2001;103:589-96

23 Limitations of TDI Angle dependency Frame rate dependency Tethering ( 묶임현상 )

24 Angle Dependency of TDI 임상심초음파학제 2 판 p187

25 Low Frame Rate TDI Data Extrapolated information 30 FPS Each square represents a frame of information More data points, More accurate waveforms!

26 Tethering( 묶임현상 ) of TDI

27 Limitations of TDI Stress Echo Angle dependent -> Need of Narrow angle Not simultaneous assessment -> Color spectral TDI (frame rate dependent) Tethering

28 Strain Rate : Rate of Deformation (Spatial velocity gradient) stress v v Strain Rate 1 2 d v 1 v 2 d No influence of translation Really local information

29 Advantage of Strain Rate Imaging vs TDI Basal septal akinesia TVI SRI cm / s s -1 cm / s s -1

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31 Peak Systolic Strain Rate during Dobutamine Stress Echocardiography Hoffmann et al. JACC 2002;39:443-9.

32 Incremental Value of SRI Assessment of Myocardial Viability after Revascularization Hanecom et al. Circulation 2005;20;112(25):

33 Baseline 10ug DSE F/60, NSTEMI s/p tirofiban EF=53% (LVEDV/ESV=80.5/37.8ml) E/E =9.38 NT-proBNP=476ng/L Lt main and 2VD, LVEDP=9mmHg, PCWP=5mmHg # (MD#97) 15 Months F/U

34 Altered Myocardial Stiffness Stunned Vs. Transmural Infarct Pislaru et al. Circulation 2004;109:

35 S E =0.7 s -1 S E =1.5 s -1 S A =0.2 s -1 S A =2.2 s -1 Baseline Dobu 20 Normal Viable by PET Nonviable by PET Viable & nonviab Peak SR E at rest 1.13± ± ± Peak SR E with dob 1.30± ± ±0.48 <.001 Peak SR E with dob 0.17± ± ± Peak SR A at rest 0.98± ± ± Peak SR A with dob 1.24± ± ±0.58 <.001 n=37 Hoffmann R, et al. Am Soc Echocardiogr 2005;18(4):330-5.

36 Strain Rate for Assessing Viability Acute myocardial infarction in man (LAD occlusion)

37 Strain Rate for Assessing Viability Recovery acute MI 1 day 2 weeks

38 Hatle L, et al, Eur Heart J, 2000 Apex Normal Base Apex Acute Inferior MI Base Apex Chronic Inferior MI Base

39 Strain Rate for Assessing Viability Acute myocardial infarction in man (LAD occlusion) [s -1 ] [s -1 ] AVC

40 Tennant R and Wiggers CJ. Am J Physiol. 1935;112:

41 Post Systolic Thickening First described by Tennant and Wiggers. Common finding in myocardial infarction. Small area of contraction interspersed by akinetic and hypokinetic segment after MI. Good predictor of viable myocardium. Underlying mechanisms are unclear. (Active fiber shortening or passive thickening)

42 Post Systolic Shortening Defined as predominantly negative Strain between AVC and E-wave (MVO) PSS < 20% of tot. Strain PSS > 20% of tot. Strain AVC MVO AVC MVO systole diastole systole diastole

43 Post Systolic Strain Index

44 Weidemann et al. Circulation 2003;107(6): Strain rate, Baseline Strain rate, Dobu 20

45 PSI

46 Automated Functional Imaging

47 Automated Functional Imaging

48 Automated Functional Imaging

49 Gobal Longitudinal Strain predicts LV remodeling in recent NSTEMI D Andrea A, et al. Int J Cardiol. 2011;153:

50 Automated Functional Imaging Exercise Echo baseline LAD os 70% LN peak

51 3D Strain

52 3D LV Strain in LD Dobutamine MR Circumferential strain in mid-ventricle Compared with normal volunteers, global left ventricular Ecc was significantly decreased in patients with ICM at rest ( versus ; P<0.001) and with dobutamine ( versus ; P<0.001). Ecc was significantly decreased in nonviable regions compared with viable segments at rest ( versus ; P<0.001) and with dobutamine ( versus ; P<0.001). Bree et al. Circulation 2006;114(suppl I):I-33-6.

53 3D Speckle Tracking Longtudinal Strain Strain 20.1% 14.9% global 3-dimensional longitudinal strains Abate E, et al. Am J Cardiol. 2012;110:

54 Take Home Message 1. Low dose dobutamine stress echocardiography showed high specificity and comparable sensitivity with other imaging modalities 2. Measurement of both systolic and post-systolic deformation both at rest and during a graded dobutamine infusion may provide prognostic information about myocardial viability. 3. Implement of these new indices in the routine clinical practice will need additional clinical and large-scale studies.

55 To be, or not to be, that is the question! Shakespeare, Hamlet, 1601

56 To be, or not to be, that is on your hands! Special thanks to Hye-Jin Kim (GE Health Korea), Eun Ok Shim, Kyeong Soon Kim, Ok Ryun Kim, Eun Ju You, Jung Geun Moon, Mi-Seung Shin (Gachon Gil Echo Lab), Dae Hee Kim, Soo-Jin Kang (Ulsan Univ.) and Goo- Yeong Cho (Hallym Univ.) for this slide.

57 Thank you for your attention!!! Wook-Jin Chung, MD, PhD Noninvasive CV Imaging Lab., HF & PAH Clinic Cardiology Division, Heart Center Gachon University Gil Hospital Incheon, Korea