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ACUSON SC2000 eSie VVI Whitepaper

ACUSON SC2000 eSie VVI Whitepaper 

Whitepaper eSie VVI Velocity Vector Imaging Technology 2D Speckle Tracking Helene Houle¹, R.D.C.S., FASE, Saurabh Datta¹, PhD, Elizabeth Hunter¹, R.D.C.S., Theresa Green², RDCS ¹ Siemens Healthineers Ultrasound ² Piedmont Medical Center SIEMENS Healthineers siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking Table of Contents 1. Introduction 3 Why Velocity Vector Imaging – 2D Speckle Analysis 3 2. Technology 4 Imaging 4 Acquisition 4 Acquisition Tips 4 Optimization 4 Tips 5 Tracking 5 3. Performing an Analysis 6 Selecting Data to Analyze 6 4. How to analyze a clip 7 Setup 7 Types of Contouring 7 5. Analysis Options 8 Regional Analysis 8 Segmental Analysis 8 Global Analysis 9 Volume Analysis 10 Phase Analysis 10 eSie VVI Technology Display Options 10 6. Analysis Options 11 eSie VVI Technology Results 11 Global Longitudinal Strain and Global Circumferential Strain 11 Prestretch 11 End Systolic Strain and Overall Strain 11 Post Systolic Index (PSI) 13 Valve Timing Events 13 Bullseye Report 13 7. Useful Tips 14 8. FAQs 15 9. Conclusion 16 10. Publications 16 2 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 1. Introduction Ultrasound-derived myocardial strain information is Multiple image-based quantitative wall motion analysis gaining clinical acceptance for diagnostic as well as prog- methods are now available. Numerous research papers have nostic reasons. Siemens Healthineers eSie VVI velocity been published touting the usefulness of Doppler-based vector imaging technology is a clinical application designed tissue imaging in quantifying wall motion analysis. This to provide visual as well as quantitative assessment of method is, however, dependent on transducer placement cardiac dynamics on the ACUSON SC2000 PRIME ultra- and only measures velocity in directions toward and away sound system. A previous version of this application is also from the transducer. Tissue Doppler Analysis still lacks available on the ACUSON X700 ultrasound system and wide clinical acceptance due to its many technical limita- ACUSON S Family systems. From 2D clips, eSie VVI technol- tions. Doppler information is limited by its angle of acqui- ogy utilizes B-mode speckle information to analyze tissue sition, requiring proper alignment of the ultrasound beams motion throughout the cardiac cycle(s). Deformation and with the myocardial wall. The clinical applications devel- kinematic parameters are derived from tissue motion and oped to extract the kinematic motion from the images is displayed qualitatively and quantitatively. With this infor- also time-consuming. This restricts the information that can mation, physicians can reliably evaluate and manage their be derived from the analysis. eSie VVI technology breaks patients’ cardiac health. through these limitations and provides multi-directional Why Velocity Vector Imaging – 2D Speckle Analysis quantification of wall motion. Cardiologists strive to assess a patient’s cardiovascular eSie VVI technology measures cardiac motion of the entire health using all clinically available tools. Historically, the myocardial wall from standard 2D imaging clips. It tracks only imaging modality available was static images of the change in tissue position based on speckle pattern from heart provided by chest X-rays, which allowed measure- sequential image frames acquired from any imaging win- ment of the heart’s size. Function was an indirect assump- dow or transducer. Once subjectively assessed subtle and tion based on the visual appearance of the heart. Today, obvious wall motion abnormalities can now easily be physicians have imaging techniques that not only provide measured, allowing for an objective diagnosis of both clin- size but also detailed anatomy, including function and flow. ical and pre-clinical conditions providing the opportunity These techniques include ultrasound, computed tomogra- to evaluate progression of disease and its treatment phy (CT), and cardiac MRI. Information from different quantitatively. modalities have recently been utilized to complete clinical diagnoses, but they still have one inherent limitation – the eSie VVI technology provides quantitative global and techniques are all qualitative mired with interpretation regional wall motion analyses of the heart providing strain, variability. strain rate, displacement, and velocity parameters. In addition, when left ventricular endocardial borders are Clinical studies have proven that visual inspection of tracked, end-diastolic, end-systolic volume and ejection patients‘ echocardiography images are insufficient to con- fraction are provided. sistently and accurately assess the heart for wall motion abnormalities. The addition of advanced imaging and test- ing methods, such as Doppler tissue imaging and stress echo, developed to enhance the visual inspection improved the qualitative analysis, but were still subjective and prone to misdiagnosis. Quantitative, objective and reproducible methods were still missing. siemens-healthineers.com/SC2000 3 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 2. Technology eSie VVI technology achieves robust wall motion analysis Position the patient in left lateral decubitus position to • by utilizing advanced speckle tracking methods. From find the optimal window. Use a breath hold technique an initial contour, defined by the user, eSie VVI technology when needed to get the best image. tracks the endocardium, epicardium or a user defined Select a depth and sector size (2D ROI) to include only • contour. Motion analysis is extracted and displayed in the desired anatomy. graphical and text form allowing for both qualitative and To increase the frame rate, narrow the B-mode sector • quantitative review. Velocity vectors (hence the name of the application) are overlaid on the tracked contour pro- to include the region of interest and adjust the depth viding a graphical display for all parameters provided. (to make the image bigger). Summarized parameters as well as a bullseye display are After processing, check and readjust the contours. If the • all available for the user to best interpret the analysis segments are not tracked well, exclude them from the results. analysis results by de-selecting the segments on the LV graphic and capture an image to record the results. Imaging • Accurate results are achieved with good image-quality data. Clips can be acquired as 60 Hz DICOM clips or acoustic This is accomplished by utilizing the optimum imaging fre- clip captures. quency and gain settings for each patient scanned. Imaging eSie VVI analysis cannot be performed on color Doppler • artifacts such as rib artifacts, image drop-outs or sub- clips or secondary reference clips from volume imaging. optimal system settings with gains set too low or too high eSie VVI analysis should also not be performed on clips • reduce analysis accuracy and can result in underestimated acquired for perfusion contrast imaging as these result in strain values. It is critical to minimize these whenever pos- varying speckle brightness throughout the cardiac cycle. sible and always set the system gains to visualize anatomy This does not apply to LVO studies and GLS method of without inducing noise. line analysis. Acquisition Optimization The best analysis results are achieved by acquiring B-mode Always optimize the image to obtain the best image quality clips at frame rates equal to or greater than 40 Hz with possible by utilizing the right transducer for the patient. the number of images within a cardiac cycle at no less than It’s important to match the frequency to the patient being 15 (see Figure 1). Although often misunderstood, this prin- imaged. Always strive for the highest resolution without ciple is key. Clips can be acquired as movie captures or cine losing penetration. data acoustic captures. System acquisition settings should be set to acquire all imaging frames and not limited to Tips Narrowing the B-mode sector to include the region of • 30 Hz, which can result in peak strain underestimation. Acquiring B-mode clips at these settings, will result in slightly interest provides a higher frame rate, but also provides larger-sized clips but increased accuracy. the highest line density. If RES is available, it can be useful in providing higher • Acquisition Tips spatial resolution. An accurate strain analysis is dependent on ECG and the • QRS complex. Always try to have the best quality possible. Acquire images on axis as it is important not to fore- • shorten apical views. This will result in overestimation of peak values and incorrect diagnosis. Effective frames per cycle at corresponding heart rates Frame per Cycle 30 bpm 60 bpm 120 bpm 30 fps 30 30 15 60 fps 60 60 30 90 fps 90 90 45 Figure 1: Effective frames per cycle at corresponding heart rates and acquisition frame rates 4 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking Frame rates ranging from 40 to 80 Hz can be used to mitral annulus. This maintains the topological shape of measure motion and deformation at normal heart rates. the trace throughout the cardiac cycle. This is also known When performing speckle tracking analysis, the frame rate as regularization. is not as important as the frames per cycle (FPC) or number of images in an R-R interval. As mechanical events become At each stage of the tracking, Fourier analysis is used and shorter with an increasing heart rate, the frame rate needed a drift compensation constraint is applied so that the trace to resolve a particular physiological event becomes higher. returns to baseline for the subsequent cardiac cycle. Therefore, the frame rate should be increased with the A confidence measure based on the uncertainty of the increase in heart rate, especially for pediatric studies, exer- results based on the imaging frame rate and the image pixel cise, and pharmacological stress exams with agents (e. g. size (transducer-dependent) is provided to help assess how Dobutamine), which increase the heart rate. Frames per good or reliable an analysis can be. Assuming all imaging cycle (FPC) are intrinsically connected with overall tracking conditions are perfect, there is a minimum uncertainty of quality, with > 30 FPC being adequate for assessment of displacement of one pixel because it‘s not possible to see GCS and GLS. FPC is the number of images in an R-R inter- below that resolution: the minimum possible visualized val. For instance, if a patient has a HR of 60 bpm (1 second displacement that can be seen between two frames is about for 1 heart cycle), and the imaging is at 60 fps, the result is one pixel. In addition, the uncertainty of small displace- approximately 30 frames in the R-R interval (1 frame every ment also occurs at high frame rates since very small dis- 15 ms). placement differences between two frames cannot be Rösner et al. (E. Heart J. – Cardiovascular Img. 2015) visually appreciated. In general, any velocity value has, in provided an eloquent analysis of this relationship and its principle, a confidence band. The accuracy measure can impact on speckle tracking results. In order to capture the be computed as follows: peak contraction of the heart, it is important to always Accuracy = 0.5*pixel size/frame time interval (ms) include enough imaging frames during the heart‘s systolic dV = ± 0.5*pixel size 27 (mm)/15 ms frame time interval motion when it moves at higher speeds. In their analysis, Roesner found that 15 frames in an R-R interval was the In the example above this band is confidence dV minimum number of frames required to safeguard under- (displacement Velocity) = 0.5*0.0272/0.0158 = 0.86 cm/s estimated strain values. The minimum frame rate limit was approximately 40 for a heart rate of 60 bpm. Tracking eSie VVI technology extracts cardiac motion estimates by tracking a user-defined contour, which is typically drawn along the endocardium. Equidistant points are positioned along the contour, which is tracked for one or more cardiac cycles. Robust estimates of the cardiac motion are then provided for each point along the contour, and points within a segment are then averaged. The individual steps are explained in greater detail below. First, the user defines a contour on the endocardium in an apical view, in which the anatomy is best seen (Figure 2). The contour is used to identify the initial region of interest to be tracked or followed from frame to frame. This is generally from end diastole to end diastole or peak of the R to peak of the next R. Because the ventricle shortens (from base to apex) when it contracts, the position of the points along the trace are adjusted during the cardiac cycle. The locations of the con- tour end points are propagated to the other frames by maximizing the local correlation of the point location on adjoining frames. For example, points halfway up each wall are adjusted to move with half of the motion of the Figure 2: Tracking of the reference plane siemens-healthineers.com/SC2000 5 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 3. Performing an Analysis Selecting Data to Analyze A good analysis always begins with high-quality images. The analysis can be performed from images acquired from Homogeneous speckle brightness throughout the image all Siemens B-mode clips. This includes standard trans- depth and image sequence improves tracking results. This thoracic transducers, transesophageal transducers, the can be achieved by using the highest imaging frequency to ACUSON AcuNav ultrasound catheter family, all vascular achieve maximum imaging penetration for each individual transducers as well as curved arrays utilized for fetal echo patient. Native TEQ ultrasound technology and IN Focus examinations. eSie VVI technology analysis can be retro- technology on the ACUSON SC2000 system are imaging opti- spectively done on previously collected clinical images mization tools that can be used to achieve these imaging documenting patient progression. requirements. Gain and depth compensated (DGC) settings should also be set to provide good penetration and struc- eSie VVI technology can analyze any vendor‘s data as long ture definition without over-gaining which creates noise in as it is stored in a DICOM format. the image. Noise is speckle tracking’s worst enemy and can Imaging artifacts such as breathing, rib noise, and trans- play havoc on results. 2D speckle tracking algorithms can- lation motion should be kept to a minimum. Again, the not differentiate between structure speckle or noise, and algorithm cannot differentiate artifact from anatomical will track both. speckles, and this can introduce uncertainties in the track- Images from technically-difficult exams can be analyzed ing results. with eSie VVI technology, but increased noise levels tend eSie VVI technology cannot be performed on color Doppler to underestimate strain and increase uncertainty. clips or secondary reference clips from volume imaging. It is also important that the whole ventricle or area of eSie VVI technology also should not be performed on clips interest be in the field of view for the whole heart cycle dur- acquired with imaging contrast agents as these have vary- ing the acquisition. A full R-to-R interval is required as the ing speckle brightness throughout the cardiac cycle, which algorithm takes advantage of the periodicity of the cardiac can impact tracking. motion. 3a 3b Rocking: +0.57 Longitudinal Strain (Endo) [Accuracy # 2.120] 30.00 1148 ms 03-Basal Inf Sept 09-Mid Inf Sept 14-Apical Septal 24.00 16-Apical Lateral 12-Mid Ant Lat D6-Basal Ant Lat 18.00 12.00 6.00 Max Opp Wall Delay 29.0 ms (14-16) GLS -19.50 % 0.00 6.00. 358.0 387.0/ 27.8 -22.5/ 358.0 3500 -12.00 -14.6 -180 18.00 477.0 -19.8 Avg(c) -18.50 Avg(s) -19.40 -13.8 -24.00 ------ Time To Peak ms Peak 30.00L LA MO AMO LA MO Mc 1148 ms 490 980 1470 : 1960 2450: 2940 3430 Figure 3a: Represents ideal image quality without imaging artifacts where overall gain and depth compensated (DGC) gains have been ideally optimized. Figure 3b: Should not be used for 2D speckle analysis as the anterior wall is not visualized. There would be high uncertainty when drawing the contour, which would result in poor tracking and inaccurate strain analysis. 6 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 4. How to analyze a clip 4 127/73 Setup Clips with and without physio information can be analyzed with eSie VVI technology. Clips with physio data will load 100% 0154/154 018/2760/2778 ms in the “Contour” step. A clip without physio information 76 bpm 55 fps will load in the “Setup” step. The user should identify the Physio Strip R-wave frame that corresponds to the end-diastolic frames Period Selector as closely as possible. The user will also need to mark an M-mode Strip imaging frame as the end of the cardiac cycle. In order to allow tracking, a clip must have a minimum of two ED frames for one heart cycle. Left clicking on the M-mode strip R-wave Indicator to the right of the frame indicator will set an ED/R-wave Figure 4: Setup screen display with Physio and M-mode strip. The marker (Figure 4). first and last heart cycle have been cropped and will be excluded eSie VVI technology allows the user to modify incorrect from the analysis results. The blue lines in the M-mode strip represent the peak of the R-wave. physio R-wave information. Clicking on an existing marker will delete an ED/R-wave detection. Users can then proceed 5 to set new ED markers to identify the start or end of the Sélecteur période heart cycle (Figure 5). Rt click on blue bar Rt click on M-mode eSie VVI technology’s flexibility allows users to exclude to delete R-wave strip to add R-wave frames or heart cycles to be tracked. Users can exclude frames by clicking and dragging the red bars on each end Figure 5: Displays the M-mode strip with blue bars representing of the physio strip display to the desired frames. the R-wave display and workflow required to add or delete R-wave In addition, users can also add a free-form M-mode. This information. provides qualitative wall motion information that should 6a 18 7 MI: 1.13 /WWW : 6,86 71 fps / 140 mm match the resulting curves. The user constructs an arbitrary- 83 bpm / NTHI allgemein H4.0MHz / 6 dB TEQ: 3 / Offset: -1. dB DB: 65 dB shaped line through the heart wall and/or valves, and an Mittel / S1 E:+1/ 00 M: D / P: 1 / F: 3 associated M-mode image is created, which will be displayed in the background of all of the graphs. Users can also per- form measurements on the resulting M-mode information. 83 bpm Types of Contouring Open, Closed, and Free-Form Contours Tracking can be initiated by tracing an open contour on the apical views and a closed contour on the short axis views. A free-form method is also provided where individual points can be set on any moving anatomy and tracked over time. MO AC MO AG , MO MG Drawing a Contour The user should select the clip to be analyzed and proceed Figure 6a: Example of eSie VVI technology virtual M-mode where to outline the chamber wall being examined. For the left a user has drawn a line across the left ventricle at the mid level. The resulting M-mode is displayed below the image, and temporal ventricle the papillary muscle should be excluded with the information is displayed on the horizontal axis. contour drawn along the compact myocardium. 6b Longitudinal Strain (Endo) 16.00 12.00 330 660 1320 2310 Figure 6b: Resulting graphical display with virtual M-mode displayed behind the curves. This additional information provides visual wall motion information. siemens-healthineers.com/SC2000 7 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 7 not follow the anatomy, the user should move the contour so that it is consistent with anatomical motion and re-start the tracking. It is recommended to draw the initial trace on a frame where the endocardial border is best seen. This is generally, but not always, a mid-systolic frame. 5. Analysis Options Regional, segmental, and global analysis results are available in the “Analysis” step. All results (parameters) are computed from tracked contours. The user can choose to review tracking results for each point on the curve, segments or global volumetric results. Regional Analysis Figure 7: Example of contours for an A4C, A4C for the right ventricle, Regional information can be derived from any tracked SAX and A4C for the left atrium. The contour should be on the inner contour, and regions of interest can be set along the curve. edge of the compact myocardium. The contour should exclude trabe- culations and papillary muscles similar to LV volume measurements. Resulting curves for strain, strain rate, velocity or dis- placement are provided. Measurements can be performed to derive peak, slope, or time-to-peak on each curve. A resulting parametric color M-mode of the tracked contour See Figure 7 to review the position of the contour for the is provided. apical left ventricle, right ventricle and left atrium. Segmental Analysis If a full myocardial thickness analysis is required, the Reviewing the tracked contour with segments provides user can add an epicardial contour. This will provide endo- a more robust, noise-independent analysis. Segmental cardium, full wall, and epicardium (endo, myo, and epi) analysis is available for the left ventricle, right ventricle analysis results. The user should select the „Endo and Epi“ and atriums. American Heart Association (AHA)‘s 16 and option in the „Contour“ step. The epi contour will be dis- 17 segment analysis is provided for the left ventricle. played at a default 10 mm distance from the endocardium. It can then be adjusted globally and regionally. Segment division is performed on the first frame of the heart cycle. The LV A4C, A2C and A3C and the A4C RV are If the clip being analyzed was acquired without an ECG divided into six even segments. The SAX basal and mid- trace, the user must manually add ED markers to define short axis views are also divided into six even segments, the start and end of each heart cycle. This is performed in and the SAX apex is separated into four segments. For the the “Setup” step of the eSie VVI technology application. 17 segmentation model, the apex is again divided into two Providing ED markers identifies heart cycles and is critical even layers, and the top layer or apical cap can be added for an accurate strain analysis. (Figures 3 and 4). It is also (Figure 9). key for the eSie VVI technology tracking performance. Atrium analysis also available, with the segmental analy- When the contour tracking is complete, the user should sis is divided into three segments – two walls and the roof. review the results and modify the trace if necessary. Peak and time-to-peak measurements are available for Tracking results should be inspected visually to assess the each analyzed segment (Figure 9). The three segmental contour and how it follows the anatomy. The resulting curves and the mean curve of all the segments are displayed curves are also useful to assess the tracking results as each with the systolic and overall peak detected automatically. curve represents a segment of the tracked contour. If the contours do not follow the anatomy, the user can modify the initial contour. On any frame where the contour did 8 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 8a 62 Cardas / Cardiac 5' 1 4Vis 9a Rocking: +0.57 ongitudinal Strain (Endo) Accuracy # 2.120] 30.00 1148 ms 03-Basal Inf Sept 09-Mid Inf Sept 24.00 14-Apical Septal 116 f:4 / 170 mm 16-Apical Lateral 55 tom / II I NTHI Cereral 100% 12-Mid Ant Lat 52 bpm D6-Basal Ant Lat 130/74 meet 0191/258 015/2832/3846 ms 12.00 67 fps +0 20102 / 14 sb 6.00 DR: 52 4B Stare in Progress Max Opp Wall Delay 29.0 ms ( 14-16 ) GLS - 19.50 9 358.0 387.0/ -22.5 -12.00 -19.8 Avg(c) -18.50 Avg(s) -19.40 13 100% Peak % 2940 -27.8 27.8 3430 40.62 56 bpm 0079/195 9b Circumferential Strain (Endo [Accuracy # 2.854) 0724 ms 017/1304/3254 ms 08-Mid Ant Sept 07-Mid Anterior 12-Mid Ant Lat 11-Mid Inf Lat 60 fps 100% 10-Mid Inferior 83 bpm 09-Mid Inf Sept 0105/250 Longitudinal Strain (Endo) % 011/1073/2580 ms 97 fps Max Wall Delay 72.0 ms (12-10) GCS -35.20 9 8b Avg(c) 34.20 Longitudinal Strain (Endo) Avg(s) 34.80 39.00 [Accuracy + 1.878] Peak % Mc 23107 0.00 9c Rocking: 40.20 39.00 MÃO 02 - Right Wall ms 340 680 : 1020 AUTO 2040 2380 8 ......... 1360 1700 64 bpm Longitudinal Strain (Endo) [Accuracy + 3.118] 013/2036/3005 ms GLS 28.70 % Time To Peak ms vacc) 32.90 38.9 31.80 28.6 53.00 L Figure 8a: Six color-coded regions of interest have been set on the Figure 9a: Represents the longitudinal segmental strain analysis tracked contour at the base, mid and apical left ventricular regions. results of an A4C view. The longitudinal strain for the endo layer Figure 8b: Graphical display of the six regions of interest, longitudinal tracking results are displayed. The LV graphic for the time-to-peak strain curve results. Below the graph is a color M-mode representing and peak overall longitudinal strain are displayed as well as the the longitudinal strain of the tracked curve over time: light to dark segmental curves and average curve for longitudinal strain. purple represents increasing negative strain, yellow to red positive Figure 9b: Represents segmental short-axis analysis for the mid- strain, and green zero strain. The lower portion of the color M-mode parasternal left ventricular short-axis view. Radial and circum- shows results for the septum, mid region, apices, and top section ferential strain analysis results are displayed with SAX LV graphic results for the lateral wall. Temporal information is represented on and curve displays. the horizontal axis for both the graph and color M-mode. Figure 9c: Represents the longitudinal segmental strain analysis of the left atrium. Global Analysis Global Longitudinal Strain (GLS) and Global Circum- This new parameter is the result of the joint EASE/EACVI ferential Strain (GCS) are the most recent clinical develop- Strain Task Force recommendation. It measures the overall ments for global functional assessment. The joint ASE/ difference of the tracked endocardial contour length. There EACVI Strain Task Force has recommended that endocardial is no segmentation of the contour and as for all Strain GLS be utilized to assess left venticular function. The measurements the initial contour is measured at the R wave recommendation comes after an inter-vendor comparison for consistency and reproducibility. of commercially available software that showed good correlation between vendors for the new parameter. The ventricular GLS and GCS results are negative values while the atrial GLS measurement is a positive value. siemens-healthineers.com/SC2000 9 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 10a The joint ASE/EACVI Strain Task Force has recommended that endocardial GLS be utilized to assess left venticular function. The recommendation comes after an inter-vendor 77 bpm 0001/142 comparison of commercially available software that showed good correlation between vendors for the new parameter. Beat: 1/2 ESV 72.4 ml EF 54 % SV 83.8 ml Global EF 54 % CO 6448.2 ml/min Average (c) – The Average (c) parameter is the peak value HR 76.9 bpm dmin 40.4 mm EDV 156.2 ml dmax 91.6 mm of the average curve. The average curve is the result of Segmental Ejection Fraction averaging the six segmental curves. 55 Average (s) – The Average (s) value is the average of the six 61 overall peaks from each segmental curve. This value is also mathematically equivalent to GLS or GCS for strain. 39 59 15'6 35% 60% 100% Volume Analysis A modified Simpson’s analysis is performed, and the 10b resulting time volume curve for LV apical views is utilized to compute end diastolic volume, end systolic volume, 64 bom 13.0000/30053 and ejection fraction. In addition, minimum (width) and 311.001 maximum (length) diameter over time is displayed. Seg- 1520 1900 2280 26 max - De mental volume time curves are derived from internal Beat: 1/3 ESV 84.4 ml 53.10 EF 56 % SV 47.2 ml cavity division where the LV is divided in half, then in Global EF 56 % CO 3061.7 ml/min HR 64.9 bpm dmin 36.5 mm equal thirds (Figure 11). EDV 37.2 ml dmax 55.5 mm 23.60 JOSE2 11.80 An area-over-time curve is provided when LV SAX, RV 15% 35% 60% 100% 5.90 0.00 51 ms 760 15.20 2280 2650 00GT and atrial views are analyzed. The segmental atrium curves 22.00 55 19.80 are the result of five layers from annulus to roof. 17.60 58 15.40 13.20 57 11.00 Phase Analysis 8.80 6.60 4.40 Phase is computed from the Fourier analysis of each seg- 2.20 Segmental Ejection Fraction 0.00 ms ORS 900 2280 2664 mental and global curve for all parameters and represents Figure 10a: Global volume analysis for an A4C view. Global time the sinusoid that best fits the specified waveform. It is volume curve, volume change rate, the min and max LV diameter reported in ms or % phase. A negative phase indicates earlier curves, the segmental volume curves and internal LV ejection fraction cartoon are displayed. A summary of the volume analysis motion, and a positive phase indicates delayed motion. results is also provided. Phase information is computed for each segmental curve Figure 10b: Example of left atrium global and segmental volume irrespective of the selected anatomy. analyses. The user has modified the ED frames to coincide with the eSie VVI Technology Display Options left atrium maximum filling, contoured the left atrial endocardium The multiple display options in eSie VVI technology are from annulus to annulus, and then tracked. The volume time curve, volume filling rate curve, minimal and maximal LA diameter curve meant to aid wall motion analysis. These include velocity as well as the segmental volume curve are displayed. The segmental vectors, point trajectory, segmental deformations, and analysis is divided in layers to evaluate the left atrial suction per- parametric display. The 3D M-mode display provides a third formance. A summarized volume analysis is provided. dimension to the parametric M-mode regional analysis results (Figure 11). 10 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 11 12 L3D 5 01 2 6. Analysis Options 3% Se Endo Vectors On Epi Vectors Off eSie VVI Technology Results Endo Trajectories Off This step provides additional parameter results for each Epi Trajectories Off segmental analysis. Included are volume information and 5% 3% Segmental Deformation OFF parameter specific measurements. The user can select to 59 42 Parametric Radial Off display results for strain, strain rate, velocity, and dis- -50 Phase +50 Parametric Long/Circ On placement. All parameters include peak and time to peak -574 574 ms Border On measurements. In addition, PreSretch Strain, Peak Overall Figure 11: Phase results reported as percentage and milliseconds Strain, and Post Systolic Index are provided (Figure 13). from a normal patient analysis. When all segments are within a normal range, the segment is displayed in green. When a segment Global Longitudinal Strain and Global Circumferential contraction is delayed, it is displayed in blue. Early contraction is Strain displayed as pink. Global Longitudinal Strain (GLS) and Global Circum- Figure 12: Represents the various display options available in ferential Strain (GCS) are the measured difference of the eSie VVI technology including: normal trajectory points for a mid tracked contour length and a global functional assess- LV SAX view, parametric velocity for a normal A4C view, segmental ment. The parameters are available for apical views (GLS) deformation for a normal A4C view, 3D M-mode strain rate, tra- and for sax views (GCS). jectory points for normal A4C view, velocity vectors for endocardial border tracking and parametric strain, and endocardial and Formula: epicardial velocity vectors of a SAX mid LV tracking. Ventricle GLS/GCS = ((min (ES) contour length – max (ED) contour length)/max (ED) contour length) *100 13 Volume Beat: 1/3 Atria GLS = ((max (ES) contour length – min (ED) EF 51 % contour length)/max (ES) contour length) *100 Global EF 51 % HR 76.0 bpm 165.8 The GLS calculation method is modified for the atria when EDV ml ESV 80.4 ml compared to the ventricular formula. In the ventricular 79 bpm SV 85.4 0001/250 3 011/0000/2706 ms 92 fps CO 6484.7 ml/min GLS formula the longest contour length occurs at ED while AV closure time 314 ms the maximum contour length of the atrial wall occurs at Longitudinal Strain Endo end systole. Seb PreStr ESS PkAll PSI TPK Ovrl % % % ms 03-E % PreStretch 03-Basal inferoseptal -13.2 -15.4 306.0 09-Mid inferoseptal -18.8 -19.2 306.0 14-Apical septal PreStretch, also known as Peak Positive Strain, is the -28.4 -29.5 317.0 16-Apical lateral -28.1 -29.0 317.0 12-Mid anterolateral -14.2 -15.1 317.0 amount of early systolic stretching occurring in the first 06-Basal anterolateral 2.0 -19.1 -20.1 306.0 Standard Dev. 0.00 6.60 6.41 6.02 100 ms of the heart cycle relative to the total combined Avg(s) 2.00 -20.30 -21.40 311.50 Avg(c) -20.20 -21.30 306.00 thickening, defined as the sum of the systolic thickening GLS -22.20 Max Opp Wall Delay 11.0 ms (09-12) (Smaxsyst) and thinning (Smaxneg) (Figure 14). Figure 13: Example of a summarized endocardial longitudinal strain Formula: for an A4C view. Each segment is numbered and labelled. PreStretch Pre-stretch = 100*Smaxneg/(Smaxneg – Smaxsyst). (early stretch), End Systolic Strain, Peak Overall Strain, Post Systolic Index, and Time to Peak Overall Strain are provided for each seg- End Systolic Strain and Overall Strain ment. The Standard Deviation, Average of all segments (AVG(s)), the End-Systolic Strain is measured at the aortic valve closure. peak of the average segmental Strain curve (AVG(c)), the Global In normal myocardial physiology, the overall peak and Longitudinal Strain (GLS) derived from the contour length are also systolic peak occur at the same time. In patients with wall provided. The maximum opposing wall delay is computed, and the segments from which it is derived provided. motion abnormalities from electro-mechanical disease (coronary artery disease, LBBB, RBBB), segments can con- tract in a discoordinated pattern with some segments reaching their maximum contraction during systole and others after end systole (Figure 15). siemens-healthineers.com/SC2000 11 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 14 Longitudinal Straine [Endo] [accuracy +2.123| 15b 0685 ms Longitudinal Strains (Endo) [accuracy # 2.123] 13.00 0695 ms 10.40 Peak Positive Strain 7.80 - Aortic Valve Closure Peak Overall Strain 5.20 2.60 0.00 2.60 -2.60 -5.20 -52 7.80 -10.40 X -13.00 ms Ac Mo Ac Mo 120 240 360 480 600 720 840 -13:00 120 240 480 600 15a . . . . Longitudinal Straing (Endo) 15c 34.00 Longitudinal Strains (Endo) [accuracy # 2.123] 27.20 13.00 0695 ms .... 20.40 ... ... ........ 10.40 OVERALL STRAIN Aortic Valve Closure 13.60- End Systolic Strain 5.20 5.80 SYSTOLIC I 2.60 0.00 STRAIN 0.00 ...... 6:80. -2.60 13.60 5.20 -7.80 . . . . . 20,40. -10.40 27.20 X . 13.00- AO Ac Mo Ao AcMo Ao 120 360 600 720 34.00 a ms. 270 540 810 1080 Figure 14: Represents an example of early stretching from a segment seen in the magenta curve. The blue curve has normal deformation and does not display any significant prestretch. Figure 15: Represents a) Time period where systolic strain and the overall strain are measured. b) Aortic valve closure time and measured Peak overall Strain measured after aortic valve closure time. c) End-systolic strain measured at the aortic valve closure time. 12 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking Post Systolic Index (PSI) 16 The amount of strain occurring after the aortic valve closure has been used as an ischemic marker. The formula Longitudinal Strains (Endo) [accuracy #2.123] 13.00 0695 ms to compute the post systolic index is as follows: 10.40 PSI = 100*(PS-ESS)/PS 7.80 End Systolic Strain where ESS = end systolic strain and PS = Overall strain Peak Overall Strain If overall peak strain occurs prior or at the aortic valve 5.20 closure time aortic valve closure, then both strains are the 2.60 same: 0.00 PSI = 100*(12-12)/12 = 0 -2.60 If a contraction delay is present, then the overall peak 5.20 occurs after the aortic valve closure: 7.80 PSI = 100*(7.0 – 10)/7.0 = 30% 10.40 Valve Timing Events eSie VVI technology provides derived valve opening and X -13.00 Ao Ac Mo ms 120 240 360 480 ; 600 closing events. Markers are available for each heart cycle. This is done by initially converting the heart cycle from ms to percentages. Each heart cycle is valued at 100%. Valve Figure 16: Example of post systolic strain with peak overall strain of timing is then set for each heart cycle. a segmental curve occurring after the aortic valve closure. The first marker aortic valve open is set at 5% after the • first R-wave. 17 Overall Peak C Ant Sept Time to Peak A3C Ant Sept The aortic valve closure event is set at + 2% time after +25% 100% • -18 A2C A C Inf Sep 345 the minimum time volume curve. A2C Ant -15 -22 323 366 304 The mitral valve opening is set at 5% after the aortic -20 -21 -17 24 281 323 289 • -30 377 346 valve closure. -27 -14 -30 336 279 313 -24 -13 304 376 375 19 Ant Lat Ant Lat The mitral valve closure is set at the last R-wave. Timing -22 events are derived after the first analysis and not modified -25% 0% 256 Inf Lat Inf La with further trackings. Tools are provided for the user to modify the timing events. Overall Peak Endo Long Strain Time to Peak Endo Long Strain Users can grab the timing indicators on the graph to the Avg A4C -20.62 º Pk A4C 320.22 ms Avg A2C -23.31 % TPK A2C 326 ms desired location. Avg A3C -17.74 % TPK A3C 319.78 ms Base -19.37 % MOWD (2-5) 88.67 ms If valve timing was measured from pulse wave Doppler or Avg(s) -20.56 % M-mode imaging, the timing bars can be modified to match. Figure 17: Represents the segmental longitudinal strain results of Bullseye Report an A4C, A2C, and A3C views bullseye display. The peak overall and A patient‘s eSie VVI technology Strain, Strain Rate, Velocity, time to peak endocardial overall strain is displayed. The gray and and Displacement analysis results can be reviewed and magenta color map utilized displays negative values in increasing archived in a 16-segment bullseye display. Separate para- magenta intensity and positive values in increasing grey intensities metric maps are provided for Strain, Strain Rate, Velocity, to provide a quick visual qualitative analysis. A summarized text and Displacement as well as Time to Peak. Overall peak display provided average values for each view and basal segments as well as the average value of all available segments (AVG(s)). and time to peak segment results are displayed in each segment. The average results per view are displayed as well as the average of six basal segments. The global average for 16 segments and the maximum opposing wall delay (MOWD) are computed and displayed (Figure 16). siemens-healthineers.com/SC2000 13 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 7. Useful Tips 18a Echocardiography and 2D speckle tracking have become clinical practice to monitor cardiotoxicity for patients undergoing chemotherapy. The key points from a 2014 ASE and EACVI expert consensus for multimodality imaging evaluation of adult patients during and after cancer therapy are: GLS is the optimal parameter of deformation for the • early detection of subclinical LV dysfunction. GLS -14.60% Ideally, the measurement during chemotherapy should • be compared with the baseline value. In patients with available baseline strain measurements, a relative per- --- centage reduction of GLS < 8% from baseline appears not to be meaningful, and those > 15% from baseline are very likely to be abnormal. If baseline GLS is -20%, a 15% reduction of the relative • percentage strain is equal to a 3% reduction of overall strain. When applying 2D strain for longitudinal follow-up of • patients with cancer who underwent chemotherapy, the GCS -34.00% same vendor-specific 2D strain application should be BP EF 58.8%, e’ 8 cm/s used. 18b Since the consensus document publication, there has been • added emphasis on the use of Global Circumferential Strain (GCS) measurement combined with GLS to better assess myocardial performance. Even if GLS has truly declined, EF may still be normal OLS -12,49 % • and GCS normal. An additional clue that a decreased GLS is genuine is if it is accompanied with an e’ velocity < 8 cm/s. In addition, when GLS and GCS are abnormal, the EF is • abnormal (< 55%) in almost all patients. GLS -12.40% Strain should not be performed if image quality is • suboptimal as a general rule. The user should select an alternative image or do not perform strain for this patient. CCS .34.49 GCS -14.40% BP EF 35.7%, e’ 5 cm/s Figure 18a: Patient with normal EF, low GLS, normal GCS, and normal e’. Figure 18b: Patient with low EF,low GLS, low CSC, and low e’. 14 siemens-healthineers.com/SC2000 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 8. FAQs Is VVI tracking based on speckle tracking? Which measurements should be performed for a standard Yes, VVI tracking is based on speckle tracking. For a full echo exam? description please review the Technology section. GLS – global longitudinal strain • Which Strain approach does VVI use? GCS – global circumferential strain • The Lagrangian strain approach is used and is the ASE/ RV GFWS – right ventricular global free-wall strain • EACVI Strain Task Force recommended method. Does the software provide a segmental tracking confi- If a segment poorly tracked can it be excluded from the dence indicator? results? A confidence score is provided. It is an indicator of the best A segment can be excluded from the analysis for the possible results given the frame rate and image resolution. average segmental and average contour results. It cannot Please see the Technology section for a detailed description. be excluded from the GLS or GCS results as these two are In addition a visual assessment of the tracked contour measured from the overall change in length of the tracked should be performed. In good results the tracked contour contour. follows the underlying anatomy. If this is not the case the Why is the apical segment excluded when evaluating the position of the original contour should be moved and segmental strain results (AVGc and AVGs)? tracking repeated. If tracking a particular segment proves The left ventricular apex rotates more than it shortens. to be difficult that segment should be excluded from the The mid and basal segments shorten more than they rotate. results. The resulting segmental curves are also indicators The apical segments are excluded for an improved assess- of tracking results and should be used to identify poorly ment of longitudinal myocardial function. tracked segments. Should there be a focus on the A4C view to measure GLS How does the software define the automated AV closure or should A2C and A3C also be included? time? The difference between the apical views averaged vs. the The automated AV closure is the result of the correspond- • 4-CH by itself is negligible. ing clips volume time curve. The minimum volume + 2% To achieve the best reproducibility, it is easier to get of the heart cycle length are used to define the AV closure • a high-quality 4-CH view for processing than all three time for each analyzed cycle. The user can modify the apical views. automated AV closure time by measuring the closure time on Doppler tracing of the AV. The measured time can then Also, in CAD, all coronary branches are included in the • be used to reposition the automated AV closure indicator. 4-CH view (see diagram below). In the instance of a small The aortic valve closure can also be visualized on the A3C localized lesion (not included in the 4-CH), abnormal view. From the A3C view advance the frames to a frame deformation will translate through the myocardium, identified as the AV closure fame. Move the timing indica- affecting the 4-CH strain results. tor to match the frame indicator. If multiple beats are ana- lyzed this step should be repeated for each beat. Has VVI been validated? RCA RCA or CX There have been multiple strain validation works published LAD 1cx LAD or CX based on VVI speckle tracking. These include validation RCA or LAD work utilizing simulated data, in-vitro strain models, in-vivo sonomicrometry and cardiac MRI comparisons in addition to normal vs pathological clinical validation work. VVI was included in the joint ASE/EACVI strain task force simu- lation, GLS and segmental strain inter-vendor comparison work. siemens-healthineers.com/SC2000 15 eSie VVI Velocity Vector Imaging Technology – 2D Speckle Tracking 9. Conclusion 10. Publications eSie VVI technology is an advanced 2D speckle tracking Head-to-Head Comparison of Global Longitudinal Strain application for the assessment of global and segmental Measurements among Nine Different Vendors. The EACVI/ myocardial mechanics using 2D B-mode image sequences. ASE Inter-Vendor Comparison Study in the Journal of the It is applicable to the left and right ventricles as well as American Society of Echocardiography both atria, and supports accurate and reproducible clinical onlinejase.com/article/S0894-7317(15)00463-0/abstract analysis of adult, pediatric and fetal heart. Parameters like global longitudinal strain (GLS) are readily available. Definitions for a common standard for 2D speckle tracking eSie VVI technology provides strain, strain rate, velocity and echocardiography: consensus document of the EACVI/ASE/ displacement deformation parameters allowing a quanti- Industry Task Force to standardize deformation imaging in tative analysis of myocardial wall motion. the European Heart Journal academic.oup.com/ehjcimaging/article/16/1/1/2403449/ A summary of results are displayed in an easy-to-read Definitions-for-a-commonstandard-for-2D- graphical bullseye display. With this tool, a mechanical speckle?searchresult=1#38867678 cardiac analysis can be performed at the bedside. Two-dimensional speckle tracking echocardiography: standardization efforts based on synthetic ultrasound data in the European Heart Journal academic.oup.com/ehjcimaging/article-lookup/ doi/10.1093/ehjci/jev197#35895903 Left Ventricular Systolic Myocardial Deformation – A Comparison of 2D and 3D Echocardiography in Children ncbi.nlm.nih.gov/pubmed/28802483 Expert Consensus for Multimodality Imaging Evaluation of Adult Patients during and after Cancer Therapy: A report from the American Society of Echocardiography and the European Association of Cardiovascular Imaging, EHJ-CV and JASE, 2014 ncbi.nlm.nih.gov/pubmed/25172399 Geometry as a Confounder When Assessing Ventricular Systolic Function Comparison Between Ejection Fraction and Strain, JACC, 2017 ncbi.nlm.nih.gov/pubmed/28818204 ASE/EACVI Strain task force publication from 2018 on LA and RV strain standardization recommendations Standardization of Left Atrial, Right Ventricular and Right Atrial Deformation Imaging Using 2D Speckle Tracking Echocardiography. A Consensus Document of the EACVI/ASE/Industry Task Force to Standardize Deformation Imaging 16 siemens-healthineers.com/SC2000 On account of certain regional limitations of sales rights Siemens Healthineers reserves the right to modify the and service availability, we cannot guarantee that all design, packaging, specifications, and options described products included in this brochure are available through herein without prior notice. Please contact your local the Siemens Healthineers sales organization worldwide. Siemens Healthineers sales representative for the most Availability and packaging may vary by country and is current information. subject to change without prior notice. Some/All of the features and products described herein may not be avail- Note: Any technical data contained in this document may able in the United States. vary within defined tolerances. Original images always lose a certain amount of detail when reproduced. The information in this document contains general tech- nical descriptions of specifications and options as well as ACUSON SC2000, eSie VVI, AcuNav, ACUSON X700 and standard and optional features, which do not always have ACUSON S Family are trademarks of Siemens Medical to be present in individual cases. Solutions USA, Inc. Siemens Healthineers Headquarters Legal Manufacturer Siemens Healthcare GmbH Siemens Medical Solutions USA, Inc. Henkestr. 127 Ultrasound 91052 Erlangen, Germany 685 East Middlefield Road Phone: +49 9131 84-0 Mountain View, CA 94043 siemens-healthineers.com USA Phone: 1-888-826-9702 siemens-healthineers.com/ultrasound Published by Siemens Medical Solutions USA, Inc. · Order-No. A91US-478-1C-4A00 · 5028 0818 online · © Siemens Medical Solutions USA, Inc., 2018

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