1. TV/TVM Tissue Doppler … Introducing Tissue Doppler What is it ?

2. TV/TVM Definition of Tissue Doppler Tissue Doppler is an emerging echocardiographic technique, which applies Doppler principles, to measure myocardial tissue velocities. Introducing Tissue Doppler Tissue Doppler is a variation of conventional Doppler. Over the last ten years, TD has been proposed as a feasible and useful imaging tool, in order to assess the regional myocardial function.

3. TV/TVM Getting the gist Introducing Tissue Doppler Technical basis Different methodologies of TV/TVM Clinical application findingsTD market analysis We will focus on the technical aspects and the different methods of Tissue Doppler. We will also deal with the clinical application findings, in order to understand and to evaluate the actual TD market needs.

4. TV/TVM Technical Principles of TD Introducing Tissue Doppler Blood Doppler Signal High velocities (100cm/s) Wide band (-fr/2, +fr/2) Low energies (TD/100) Tissue Doppler Signal Low velocities (10cm/s) Narrow band (-fr/8, +fr/8) High energies (BD*100) Tissue Doppler No aliasing (-fr/8, +fr/8) Different filters (gain adjustator) In current Doppler blood flow studies, the low Doppler shift frequencies, of high energy (40dB), generated by the myocardial wall motion, are purposely filtered out. Since these low Doppler shift frequencies are produced by contracting myocardium, they are expected to contain potential information for the assessment of myocardial properties. Early description of this technique have already suggested its potential to evaluate both systolic and diastolic myocardial function.

5. TV/TVM Tissue Doppler modalities Tissue Velocity (TV) Quantitative Assessment Tissue Velocity Mapping (TVM) Semi-Quantitative AssessmentQualitative Assessment Mono-dimensional Bi-dimensional The velocity of moving tissues can be studied with pulsed wave tissue Doppler sampling, which displays the velocity of a selected myocardial region against time. In addition, the velocities can be calculated with time velocity maps and displayed as color coded velocity maps, in either M-mode or two-dimensional format. The velocity of moving tissues can be studied with pulsed wave tissue Doppler sampling, which displays the velocity of a selected myocardial region against time. In addition, the velocities can be calculated with time velocity maps and displayed as color coded velocity maps, in either M-mode or two-dimensional format.

6. TV/TVM Tissue Doppler modalities * The overall function of the left ventricle depends on a normal contraction of the longitudinally and circumferentially orientated fibers. * Quantification of the LV function, in the longitudinal axis, may be clinically relevant since the contraction in this direction is mainly due to subendocardial fibers. In particular, one can expect that in case of ischemia, which specifically alters subendocardial layers, first abnormalities of wall motion will appear in the longitudinal axis. * As the apex of the heart remain remarkably stationary, long axis changes are reflected in movements of the base of the heart. What are we actually measuring ? Epicardial and subendocardial fibers Longitudinally orientated fibers Longitudinal function Intramiocardial fibers Circumferentially orientated fibers Circumferential function

7. TV/TVM Tissue Doppler modalities Tissue Velocity (TV) Quantitative Assessment of regional myocardial function Sample Volume positioning (Longitudinal dynamics) Locate the sample volume at the lateral margin and at the common septal margin of the tricuspid and mitral anuli. S 2.5 ± 1.2 cm/s 7.5 ± 1.9 cm/s A 5.4 ± 2.3 cm/s 6.3 ± 2.1 cm/s E 10.8 ± 3.1 cm/s 14.6 ± 3.6 cm/s The PW-TD pattern can be divided into two parts, systolic and diastolic, from which several measurements can be obtained. The systolic phase is characterized by a positive wave S preceded by the time taken from regional isovolumic contraction (RIVCT). The diastolic phase, which is more complex, is composed of 4 periods. The regional isovolumic relaxation (RIVRT). The rapid filling period, characterized by a negative wave E. The diastasis, which doesnt exhibit any movements, and the filling period due to atrial contraction, represented by a second negative wave A.

8. TV/TVM Tissue Velocity (TV) Tissue Doppler modalities Quantitative Assessment of regional myocardial function Advantages : high temporal resolution v [cm/s], a [cm/s2] rapid quantification Inconveniences : manually mapping no simultaneous recording low wall filter and low gain setting Pulsed-wave-TDI provides real-time Doppler signals with high temporal resolution, but allows only step by step evaluation of single sampling points of interest. Therefore, reproducibility may be lower than for color-Doppler-TDI. Pulsed TD permits to obtain high quality Doppler signals, due to its high temporal resolution. To measure, in addition to velocity, mean and instantaneous acceleration and to obtain rapid quantification of these magnitudes. However, pulsed TD suffers from the following limitations. The need for manually performed mapping, the impossibility of simultaneous recording of different ventricular wall segments. Although pulsed Doppler signals can be obtained with all available commercialized US machines, a low wall filter and low gain settings are needed to obtain high quality signals.

9. TV/TVM Tissue Velocity Mapping (TVM) Tissue Doppler modalities Semi-Quantitative Assessment of regional myocardial function M-mode color TD of the myocardium allows us to superimpose wall motion velocity on the mono-dimensional echocardiographic imaging, by velocity color coding. M-mode color TD of the myocardium allows us to superimpose wall motion velocity on the mono-dimensional echocardiographic imaging, by velocity color coding. Depending on the orientation of the cardiac structures relative to the US beam, the velocity signals appear red or blue according to movement of the myocardium towards or away from the transducer, respectively. Moreover, different color coding scales reflect different velocities: low velocities are coded with dark colors, while high velocities are coded with bright colors. The M-mode color TD from the parasternal and apical views, allows the analysis of contraction and relaxation of circumferential (intra- myocardial) and longitudinal (sub-endocardial) fibers, respectively. M-mode color TD of the myocardium allows us to superimpose wall motion velocity on the mono-dimensional echocardiographic imaging, by velocity color coding. Depending on the orientation of the cardiac structures relative to the US beam, the velocity signals appear red or blue according to movement of the myocardium towards or away from the transducer, respectively. Moreover, different color coding scales reflect different velocities: low velocities are coded with dark colors, while high velocities are coded with bright colors. The M-mode color TD from the parasternal and apical views, allows the analysis of contraction and relaxation of circumferential (intra- myocardial) and longitudinal (sub-endocardial) fibers, respectively.

10. TV/TVM Tissue Velocity Mapping (TVM) Tissue Doppler modalities Advantages : high spatio-temporal resolution Δt [s] Inconveniences : single line low wall filter and low gain setting Mono-dimensional TVM M-mode color-coded TD is characterized by a high spatio- temporal resolution, but sampling is performed only on a single line. Moreover, it requires specific modification of the conventional US scanner..

11. TV/TVM Tissue Doppler modalities Qualitative Assessment of regional myocardial function Tissue Velocity Mapping (TVM) Like in the Color Doppler application, in TD the different velocities are correlated with a preset colour scheme and, super-imposed on the 2-dimensional image displayed as colour flow on the monitor. Blood flow towards the transducer is colour-coded in red shades while blood flow away from the transducer is colour coded in shades of blue. Color TD of the myocardium allows us to superimpose wall motion velocity on the two-dimensional echocardiographic imaging, by velocity color coding. Depending on the orientation of the cardiac structures relative to the US beam, the velocity signals appear red or blue according to movement of the myocardium towards or away from the transducer, respectively.

12. TV/TVM Tissue Velocity Mapping (TVM) Tissue Doppler modalities Advantages : rapid visual qualitative assessment high spatial resolution analysis of simultaneous regions Inconveniences : weak temporal resolution low wall filter and low gain setting Bi-dimensional TVM Two-dimensional color TD allows a rapid visual qualitative assessment of the dynamics of the wall, provides a good spatial resolution that permits differentiation of the velocity profiles between subendocardial and subepicardial layers and allows us to analyze simultaneously various myocardium regions. However it is limited by its poor temporal resolution which varies according to the system used and ranges from 100 ms in first generation scanners, to 10 ms in the new fully-digital systems. Moreover, it requires specific modification of the conventional US scanner.

13. TV/TVM Clinical Applications : TTE Transthoracic approach Hospitals Sport Medicine Research Diastolic Function Myocardial ischemia Cardiomiopathy

14. TV/TVM Clinical Applications : TEE Transesofageal approach Clinical Applications Multisite stimulation in refractory heart failure Wolff-Parkinson-White syndrome Left atrial appendage Electrophysiology department

15. TV/TVM The…… End……