Cardiac Chamber Quantification by Echocardiography Maryam Bokhamseen, RCS, RCDS, EACVI Echotechnologist ǁ, Non invasive Cardiac Laboratory King Abdulaziz Cardiac Center.
Outline: Introduction. Background of echo. Recommendations for the echocardiography assessment of LV size and function Tutorial How can we perform 3D Full volume and Global Longitudinal Strain. Take home message.
Introduction: The quantification of cardiac chamber size and function is the cornerstone of cardiac imaging, with echocardiography. being the most commonly used noninvasive modality because of its unique ability to provide real-time images of the beating heart, combined with its availability and portability.
The Father Of Echocardiography
Christian Doppler (1803-1853) Famous for what is called now the Doppler effect
Echo as leading cardiac modality of imaging: A Long Journey of Success A-mode M-mode 2D 3D? Doppler (blood pool) Tissue doppler Speckle tracking
January 2015
How do we Assess LV Function? Eye ball Qualitative Assessment Subjective Experience dependent Lack of standardization Large inter-and-intraobserver variability
Internal Linear Dimension 3-D data sets Global longitudinal Strain Recommendations for the echocardiographic assessment of LV size and function Endocardial border enhancement 2-D Guide linear measurment Biplane Disk summation
1 Internal Linear dimensions (M-Mode) 2-D guided Linear measurment Volume (Biplane disk summation) Endocardial border enhancement (contrast agent) 3-D Data sets Global longitudinal Strain
1-Internal linear dimension. M-mode or motion mode provide 1D view, where a single scan line is placed along the area of interest. The M-mode is then show how the structures intersected by that line move toward or away from the transducer over the time.
It has a good temporal resolution, so it is useful in detecting and recording rapid movements structure such as a heart. It is commonly used for measuring chamber dimensions, calculating fractional shortening and ejection fraction
Internal Linear Dimension Advantage: Reproducible High temporal resolution Disadvantage: Beam orientation frequently off axis Rely on the assumption of fixed geometric LV shape (ellipsoid) which does not apply in all cardiac pathology.
Internal Linear Dimension 90 Degrees 120 Degrees = 7 X D3 2.4 + D In PLAX The scan line is placed perpendicular to LV at MV leaflet tip
Internal Linear Dimension 120 Degrees
2 Internal Linear dimensions (M-Mode) 2-D guided Linear measurment. Volume (Biplane disk summation) Endocardial border enhancement (contrast agent) 3-D Data sets Global longitudinal Strain
2-2-D guided Linear measurement
3 Internal linear dimension 2-D guided linear measurements. Volume (biplane disk summation) Endocardial border enhancement (contrast agent) 3-D data sets Global longitudinal strain.
3-Biplane disk summation Apical 4 Apical2 Diastole Systole
Biplane disk summation b h a Volume of disk=π a/2 b/2 h
Biplane disk summation 20 Disks 20 Disks EF =( LVD - LVS ) / LVD
LV EF % Normal Rang Mildly abnormal Moderately abnormal Severely abnormal Male 52-72 % 41-51 30-40 < 30 Female 54-74 % 41-53 30-40 < 30 Normal ranges and severity partition cutoff values for 2DE-derived LV EF
Internal linear dimension 2-D guided linear measurements. Volume (biplane disk summation) 4 Endocardial border enhancement (contrast agent) 3-D data sets Global longitudinal strain.
4-Ultrasound contrast agent: It is Stabilized gas (Microbubble) sized to pass Through the smallest capillaries. Microspheres:2-8 ϻm RBC:6-8 ϻm
What is contrast made of? 2-8ϻm Gas Air PFC Nitrogen SF6 Shell Lipid Albumin Surfactant Glactose polymer Non-toxic Small to pass through pulmonary vasculature. Persistent enough to reach the LV / myocardium and withstand left-side pressure.
Mechanical index (MI) MI = peak negative pressure Frequency Low MI <.3 with harmonic F
Advantage: Helpful in patient with suboptimal acoustic window. Helping in Quantification of LV volume &EF. For better visualization of cardiac apex. Disadvantage: Acoustic shadowing in LV basal segment. Swirling artifact.
55 Years old female has cardiomyopathy, refer to our lab to R/O LV Clot.
1.1 X 1 cm
49 Years Old male has CHF. refer to our Lab to R/O LV Non compaction.
Ratio 3:1
ED = 399 ml
ES = 317 ml EF < 25 %
Internal linear dimension 2-D guided linear measurements. Volume (biplane disk summation) Endocardial border enhancement (contrast agent) 5 3-D data sets Global longitudinal strain.
5-3-D Data sets. Why do we need another (D) in echo? What wrong with 2-D echo? Because the heart is a 3D Object!!
Because the heart is a 3D Object!! heart
2-D Imaging Lateral dimension Longitudinal dimension
3-D Imaging Elevation Dimension Lateral Dimension Longitudinal Dimension
How To Performed 3D Full volume.
3DQ Advance
S L A I
Surface Rendering Volume(ml)) up to 5% Normal 5-10 Mild 10-20 Moderate >20 % Sever Time (sec)
Advantage: No geometrical assumption. Unaffected by foreshortening. Disadvantage: Lower temporal resolution. Image quality dependent.
Internal linear dimension 2-D guided linear measurements. Volume (biplane disk summation) Endocardial border enhancement (contrast agent) 3-D data sets 6 Global longitudinal strain.
6-Global Longitudinal Strain. Strain(ε), describe myocardial deformation, that is, the fractional change in the length of myocardial segment. Strain can be positive or negative which reflect lengthening or shortening respectively.
Global Longitudinal Strain Ɛ = L L0 = ΔL L0 L0 Strain is unit less and expressed as %
25 Years old Patient with Normal Heart
Global longitudinal strain
GLS Y X
GLS
GLS Y X
GLS
GLS Y X
Adantage: Angle independent. Minimally affected by intra and inter observer variability. Not affected by cardiac translation movement. Disadvantage: Vendor dependent.
Take home massage: M-mode has limitation due to geometric assumption but still useful due to high temporal resolution. Simpsons is recommended to calculate LV volume but still subjective to LV foreshortening. Contrast is useful for LV opacification and should be used if two contiguous segments are poorly visualized in Apical view. 3D is new imaging modality and we should use it Strain is a good predictor for LV systolic function.
If you fail never give up because F.A.I.L means First Attempt Is Learning End in not the end E.N.D means Effort Never Dies If you get No as an answer,remember N.O means Next Opportunity Lets be positive
Thank You