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Echocardiography. Left Ventricular Systolic Function. Basic Principle. Basic Principle. Systole The period of the cardiac cycle from the closure of the mitral valve to the closure of the aortic valve. Basic Principle. Phases IVCT Ejection phase. Basic Principle. IVCT
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Echocardiography Left Ventricular Systolic Function
Basic Principle Systole The period of the cardiac cycle from the closure of the mitral valve to the closure of the aortic valve.
Basic Principle • Phases • IVCT • Ejection phase
Basic Principle IVCT • Time from MV closure to AV opening
Basic Principle • Mitral valve opens when the LAP is greater than LVP. • Mitral valve closes when LVP is greater than LAP. • Aortic valve opens when LVP is greater than aortic pressure. • Aortic valve closes when the aortic pressure is greater than LVP.
Evaluation of LV Systolic Function • Evaluation • M- mode • Two Dimensional • Doppler
Evaluation of LV Systolic Function ESD = LVIDs EDD = LVIDd FS= LVIDd - LVIDs LVIDd
Evaluation of LV Systolic Function EF = LVIDd3 – LVIDs3 LVIDd3
Evaluation of LV Systolic Function Single Plane Ellipsoid Uses the length and area A of a single long-axis view. Left ventricular volume is calculated assuming an ellipsoid shape as: V = 8 A2 3 p L
Evaluation of LV Systolic Function A is measured by tracing the endocardial borders.
Evaluation of LV Systolic Function Hemi-cylindrical Hemi-ellipsoid Model Assumes: Base of ventricle = cylinder Apex of ventricle = ellipsoid Volume is calculated using a long axis length L and cross-sectional area Am of an orthogonal short-axis view at the mid-papillary muscle. V = (Am) L/2 + 2/3 (Am) L/2 V = 5/6 AL (Bullet Formula)
Evaluation of LV Systolic Function In the presence of regional wall motion abnormalities all the above methods will be less accurate, since if the region of abnormal wall motion is included in the dimension or area measurements, volumes will be overestimated.
Evaluation of LV Systolic Function The apical biplane methods are more robust in this setting, using summation of a series of disks from apex to base (often called Simpson’s Rule).
Evaluation of LV Systolic Function The ASE (American Society of Echocardiography) recommends use of biplane apical views with a modified Simpson’s rule approach..
Evaluation of LV Systolic Function For this method, endocardial borders are traced in apical four-chamber and two-chamber views and are used to define a series of orthogonal diameters (a and b) as follows: V = (p ) S ai bi x (L) 4 20 Using 20 disk for i = 1 to i = 20 This calculation is done by computer software.
Evaluation of LV Mass This is done by tracing the epicardial to calculate the total ventricular volume and the endocardial border to calculate chamber volume. LV mass = 1.05 (total volume – chamber volume)
Evaluation of LV Mass LV Total Area
Evaluation of LV Mass LV Cavitary Area
Evaluation of LV Mass Length
Evaluation of LV Mass Total volume= Total area x length Chamber volume = Chamber area x Length Myocardial volume = Total volume – Chamber volume LV mass = Myocardial volume x density LV mass = Myocardial volume x 1.05
Doppler Stroke Volume Calculation • Assumption used for measuring SV using Doppler are: • Accurate cross-sectional flow area measurement. • Laminar Flow. • Spatial ‘flat’ flow velocity profile. • Parallel intercept angle between Doppler beam and • direction of blood flow. • 5. Velocity and diameter measurements are made at the • same anatomic site.
Doppler Stroke Volume Calculation • Measurement Location • Ascending aorta • Aortic valve leaflet tips • LVOT
Doppler Stroke Volume Calculation • Ascending aorta • Measure • Diameter in PLAX • VTI from an apical or suprasternal approach with • PWD.
Doppler Stroke Volume Calculation • Ascending aorta • Measure • Diameter at Sinotubular junction • VTI from apical or suprasternal approach using • CWD.
Doppler Stroke Volume Calculation • Leaflet Tips • Diameter in PLAX at leaflet tip • VTI from an apical or suprasternal approach • with PWD.
Doppler Stroke Volume Calculation • LVOT • Diameter measured in PLAX , immediately adjacent to the aortic valve in midsystole from the septal endocardium to the leading edge of the anterior mitral valve leaflet.
Doppler Stroke Volume Calculation LVOT PWD is used form an apical approach to record the velocity curve, using the closing click of the aortic valve to ensure that the sample volume is located at the annulus.
Evaluation of LV Systolic Function • The other Doppler measurements that can be used to measure LV systole function are • Peak velocity • Mean acceleration • Acceleration Time • Deceleration Time • Ejection time • Mean deceleration
Evaluation of LV Systolic Function Ejection Time Deceleration Time Acceleration Time Mean Acceleration Peak Acceleration Peak velocity