Tissue Doppler and Strain Imaging Steven J. Lester MD, FRCP(C), FACC, FASE Relevant Financial Relationship(s) None Off Label Usage None 1
Objective way with which to quantify the minor amplitude and temporal subtleties in motion 2
1. What is myocardial imaging? 2. Potential Clinical Applications 3. Impediments to widespread clinical adoption? Doppler Tissue Imaging 1. Turn wall filters off 2. Turn down the gain 3
Septal Myocardial Velocity Traces S1 S2 Velocity: Base to Apex gradient Strain: Apex to Base gradient (small) FORESHORTENED IMAGES! e a Normal 4
To Detect Regional Wall Motion Pulsed TD Peak Velocities Color TD Mean Velocities 14 11 5
Translation and Tethering Strain = deformation resulting from applied force Stress = force Courtesy of Ted Abraham 6
Used to describe elastic properties of cardiac muscle (Mirsky and Parmley: Circ Res, 1973) Strain ( ) = L 1 -L 0 L 0 10 cm L 0 L 1-20% Strain rate 8 cm +20% 12 cm 0% 10 cm Rate of deformation High strain rate Low strain rate Equal strain Courtesy of Andreas Heimdal 7
AoC Basal Mid wall Apical Basal Mid wall Apical Movement of the myocardium relative to the sample volume fixed in space 8
Speckle Tracking Velocity is estimated as a shift of each object divided by time between successive frames (or multiplied by Frame Rate)--> 2D vector: (Vx, Vy) = (dx, dy) * FR Y dy 0 dx New location Old location X Courtesy Peter Lysysanksy Potential Advantage? Signal noise Speckle tracking by principle is angle independent Gray scale (standard views) Monitor strain in two rather than one dimension Minimal user input Assessment of rotation: derived from circumferential strain at different levels in the heart (NO fixed sample volume) 9
Rotation/Twist/Torsion Rotation Rotation and Torsion Basal Rotation Torsion Apex View from apex 10
Normal Abnormal relaxation Pseudonormalization Restriction Mitral flow E A Tissue Doppler E A Apical rotation Basal rotation LV torsion Park et al: J Am Soc Echo Cardiogr 21:1129, 2008 Negative Values Routine Practice Positive Values 11
Global Longitudinal Peak Systolic Strain (GLS) Members of the in Chamber the range Quantification of -20% Writing Group are: Roberto M. Lang, MD, FASE, et al - Optimize image quality, maximize frame rate and minimize foreshortening. - When regional tracking is suboptimal in more than two J Am myocardial Soc Echocardiogr segments 2015;28:1-39 in a single view the calculation of GLS should be avoided. Aortic Valve closure 12
Good Bad -17% -8% Good Bad -17% -16% -13% -14% 13
Good Bad -16.6% -12.6% 24% Difference 14
Potential Clinical Applications Impaired Systolic Function by Strain Imaging in Heart Failure With Preserved Ejection Fraction Strain Imaging detects impaired systolic function despite preserved global LVEF in HFpEF that may contribute to the pathophysiology of the HFpEF syndrome. J Am Coll Cardiol 2014;63:447-56 15
Strain (%) 0 Controls Hypertensive Heart Disease HFpEF -5-10 Longitudinal Circumferential -15-20 * * -25-30 * * *p<0.0001 compared to controls and between HHD and HFpEF J Am Coll Cardiol 2014;63:447-56 Longitudinal Strain NT-proBNP 16
Cardio-Oncology 17
76 year old male CMML/MDS with associated myeloid sarcoma skin lesions Experimental Chemotherapy ABT-348 Baseline 2 Months LVEF = 66% LVEF = 58% CTRCD if decrease in LVEF >10% to a value <53% 18
Baseline 2 Months LVEF = 66% LVEF = 58% GLS of <8% from baseline appears not to be meaningful, and those >15% from baseline are very likely to be abnormal Change In Strain: (17.8 14.3) / 17.8 = 19.7% GLPSS Avg = -17.8% Troponin T = 0.02 GLPSS Avg = -14.3% Troponin T = 0.03 19
Anthracyclines and Trastuzumab Can we predict a later (3 months) decline in LVEF? No decrease in GLS > 10% or elevated hstni have a 3% probability of a decrease in LVEF. If either a decrease in GLS or elevated hstni have a 9X increased risk for cardiotoxicity compared to those with no changes in either of these markers. - CTRCD GLS is the if decrease optimal parameter in LVEF >10% of deformation to a value <53% for the early -Reversible: detection of to subclinical within 5 percentage LV dysfunction. points of baseline - In patients with available baseline strain measurements, -Partially reversible: a relative improved percentage by >10 reduction percentage of points GLS from of <8% the nadir from but baseline remaining appears >5 percentage not to be points below meaningful, baseline and those >15% from baseline are very likely -Irreversible: to be abnormal. improved by <10 percentage points from the nadir and remaining >5 percentage points below baseline 20
Athlete HTN HCM Infiltrative -amyloid Storage -Fabry The Thinker Auguste Rodin 21
Application of a Parametric Display of Two-Dimensional Speckle-Tracking Longitudinal Strain to Improve the Etiologic Diagnosis of Mild to Moderate Left Ventricular Hypertrophy J Am Soc Echocardiogr 2014;27:888-95 22
Cardiac Amyloidosis Hypertensive Heart Disease Hypertrophic Cardiomyopathy 14mm 14mm 13mm Mean Wall Left Ventricular Thickness 23
Up to 50% with asymptomatic severe AS and preserved LVEF will have subclinical LV dysfunction as noted by reduced longitudinal strain. Low longitudinal strain Independent predictor of symptom development More likely to have an abnormal BP response to exercise J Am Coll Cardiol Img 2014;7:1151-66 Higher rates of cardiac events at follow up LVEF > 50% LVESD < 50mm LVEDD < 65mm LVEF > 50% Vmax <5m/s ΔPmean <60mmHg Normal ETT ΔVmax <0.3m/s/yr Asymptomatic (Stage C) LVEF >60% Positive LVESD <40mm Stress Test Sinus Rhythm LVEF >60% PASP LVESD <40mm <50mmHg Rest LV GLS Sinus Rhythm Successful PASP <50mmHg Repair <95% (<) -18% Successful Repair <95% Or Mortality >1% >1% Very Severe MVA<1cm 2 T 1/2 > 220 - Unfavorable morphology, LA clot, > mild MR Severe MVA<1.5cm 2 T 1/2 > 150 -Sinus rhythm -Afib with Unfavorable morphology, LA clot, > mild MR Aortic Regurgitation* Aortic Stenosis Mitral Regurgitation Mitral Stenosis Valve Active Replacement / Surveillance Repair? *ACC/AHA NOT ESC guidelines 24
Primary MR (Stage C) LVEF 30-60% or LVEDD > 40mm (stage C2) LVEF >60% and or LVEDD < 40mm (stage C1) New onset AF or PASP > 50mmHg (stage C1) Progressive increase in LVESD or decrease in LVEF Likelihood of successful repair > 95% and expected mortality < 1% Yes No MV Surgery* (I) MV Surgery (IIa) MV Repair (IIa) Periodic Monitoring Nishimura et al J Am Coll Cardiol 2017 Valve Focused Update Impediments to Clinical Adoption? 1. Standardization 2. Workflow 25
-30-18.8 ±3.4-20.2 ±3.6-21.0 ±3.9-18.8 ±3.6-18.2 ±3.6-20.0 ±3.6-18.5 ±3.2-18.5 ±3.1-21.5 ±4.0-19.4 ±3.3-20 GLS AV, % -10 0 Hitachi-A Esaote GE Philips Samsung Siemens Toshiba Epsilon Tomtec Mean of All Farsalinos et al. J Am Soc Echocardiogr 2015;28:1171-81 26
20 19.7 17.0 Mean Error, % 15 10 12.2 11.6 8.2 6.9 5 0 GLS AV E E/A IVS LVEDD PW GLS AV Farsalinos et al. J Am Soc Echocardiogr 2015;28:1171-81 12 10.1 10 8.6 8.1 GLS AV, % 8 6 5.9 6.5 6.5 6.8 6.2 5.4 5.3 4 2 0 Hitachi-A Esaote GE Philips Samsung Siemens Toshiba Epsilon Tomtec EF BI Farsalinos et al. J Am Soc Echocardiogr 2015;28:1171-81 27
Any innovation in imaging must be paralleled or exceeded by an innovation in workflow. Fully Automated Versus Standard Tracking of Left Ventricular Ejection Fraction and Longitudinal Strain The Fast-EFs Multicenter Study J Am Coll Cardiol 2015;66:1456-66 28
1. AutoLV measurements were feasible in 98% of studies. 2. Average analysis time was 8+1 sec/patient. 3. Interobserver variability was higher for both visual and manual EF, but not different for LS. 29
Lower resolution (spatial and temporal) a promising approach J Am Soc Echocardiogr 2012;25:68-79 30
What s Next Starts Soon Standardization Workflow Efficiency Confucius It doesn t matter how slowly you go as long as you do not stop 31
1. DTI characterizes the low velocity, high intensity signals that come from the wall. 2. DTI is limited to movement relative to the sample volume fixed in space 3. Velocity: pitfalls of tethering and translational motion 4. Local parameters of deformation (strain and strain rate) are not influenced by tethering or translational motion 5. Feature or Speckle tracking can evaluate velocity, strain and strain rate from standard gray scale images 6. Feature tracking permits assessment of strain in the axis of movement rather than the axis of the ultrasound beam. 32
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