Basics in echocardiography - an initiative in evaluation of valvular heart disease
-
Upload
praveen-nagula -
Category
Education
-
view
318 -
download
1
Transcript of Basics in echocardiography - an initiative in evaluation of valvular heart disease
![Page 1: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/1.jpg)
An initiative in the evaluation of
Valvular Heart Disease
![Page 2: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/2.jpg)
Echocardiography remains the most frequently used and usually the
initial imaging test to evaluate all cardiovascular diseases related to a
structural, functional, or hemodynamic abnormality of the heart or
great vessels.
Uses the ultrasound beams reflected by cardiovascular structures to
produce characteristic lines or shapes caused by normal or abnormal
cardiac anatomy.
Doppler and colorflow imaging provide reliable assessment of cardiac
hemodynamics and blood flow.
![Page 3: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/3.jpg)
![Page 4: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/4.jpg)
![Page 5: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/5.jpg)
Single dimension
Graphically represents the motion of cardiac structures.
Used primarily to measure cardiac chamber size.
Timing of cardiac events.
Display subtle abnormalities of cardiac motion.
For determination of LV mass.
May overestimate the dimensions if the direction of ultrasound
beam is oblique to that structure.
![Page 6: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/6.jpg)
![Page 7: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/7.jpg)
![Page 8: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/8.jpg)
Volumetric flow
Spatial pattern of flow
LV outflow
RV outflow
LV inflow
RV inflow
Left atrial filling (pulmonary vein flow)
Right atrial filling (SVC,IVC)
Descending aorta
![Page 9: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/9.jpg)
Overall pattern of intracardiac flow is better demonstrated.
Angle dependent.
Physiologic valvular regurgitation.
![Page 10: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/10.jpg)
Agitated saline
Specific contrast agents
For detection of intra cardiac shunts
For delineation of cardiac borders
For detection of PFO
![Page 11: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/11.jpg)
![Page 12: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/12.jpg)
In evaluation of valvular heart disease
![Page 13: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/13.jpg)
During the past 20 years, echocardiography has gradually replaced
cardiac catheterization for most hemodynamic assessments in most
clinical practices.
Less than 5% pts undergo hemodynamic cardiac catheterization
before AVR for AS.
Less than 50% pts undergoing pericardiectomy.
Doppler hemodynamic assessment is sometimes more reliable,
accurate than invasive hemodynamic assessment, the best example
being Transmitral pressure gradient(PCWP used as LA pressure).
![Page 14: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/14.jpg)
Peak(Maximal) instantaneous gradient is measured(Peak to
peak in invasive).
Mean gradient – average of pressure gradients during the entire
flow period.
Bernoulli principle.
Simplified Bernoulli equation.
![Page 15: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/15.jpg)
P = 4V² or (2V) ²P =pressure difference
V = maximal velocity recorded across orifice by
CW doppler.
![Page 16: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/16.jpg)
The simplified bernoulli equation ignores the proximal flow
velocity (v1) and estimates gradient based on the distal,or jet
velocity (v2),this is an acceptable simplification if v2 is
significantly greater than v1.
In case of proximal velocity (v1) is relatively high, this
simplification may be inappropriate.
If the gradient is low,the difference between v1 and v2 may be
relatively small and a more appropriate version of bernoulli
equation would be.
P = 4 (Vd² - Vp²)
![Page 17: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/17.jpg)
Flow velocities recorded with doppler echocardiography are
used to determine various intracardiac pressures.
1.Pulmonary artery pressures Tricuspid regurgitation jet velocity gives the systolic pressure
difference between RV and RA.
TRJV = (RVSP - RAP)
RVSP = TRJV +RAP
RVSP = PASP in absence of any stenosis.
![Page 18: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/18.jpg)
Pulmonary regurgitation velocity represents the diastolic pressure
difference between the pulmonary artery and PV.
PAEDP = RVEDP + 4(PREDV)²
PAEDP = RAP + 4(PREDV)²
PA Mean Pressure = 4(PR peak velocity)² .
![Page 19: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/19.jpg)
PRJV
PREDV
![Page 20: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/20.jpg)
AR velocity reflects the diastolic pressure difference between the
aorta and the left ventricle.
LVEDP = DBP – (AREDV)² 4
DBP = Diastolic Blood Pressure
EDV =End Diastolic Velocity.
![Page 21: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/21.jpg)
According to the hydraulic orifice formula, flow (rate) across a
fixed orifice is equal to the product of the cross sectional area
(CSA) of the orifice and flow velocity:
Flow rate : CSA Flow velocity.
In hemodynamic calculations of flow, SV and orifice area by
doppler echocardiography.
TVI – flow velocity varies during ejection in a pulsatile
system,individual velocities of the doppler spectrum need to be
summed (i.e. integrated) to measure the total volume of flow
during a given ejection period.sum of velocities is called time
velocity integral.
SV = CSA TVI
![Page 22: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/22.jpg)
Mostly LVOT is used to determine the stroke volume.
CSA of the orifices in the heart is usually assumed to be a circle, and
is determined by measuring the orfice diameter (D)
CSA = (D/2)²
CSA = D² 0.785
SV = D² 0.785 TVI
Cardiac output = SV HR
Cardiac index = CO /BSA
![Page 23: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/23.jpg)
Based on conservation of mass.
A1 TVI1 =A2 TVI 2
![Page 24: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/24.jpg)
Originally developed for evaluating patients with mitral
stenosis.
Time required for the peak pressure gradient to be reduced by
one half.
Time required for the peak velocity to decrease to a value
equal to peak velocity divided by 2.
Time required for the initial velocity to decrease to a value of
peak velocity divided by 1.4.
Peak velocity multiplied by 0.7
PHT increases with increase in stenosis.
![Page 25: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/25.jpg)
Volumetric method:
RV = Aortic systolic flow – Mitral diastolic flow.
Regurgitant fraction (%) = Regurgitant volume / aortic outflow
volume *100%.
ROA = flow rate /Velocity
![Page 26: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/26.jpg)
Novel application of continuity principle.
As blood converges toward an orifice,doppler flow imaging
reveals concentric shells or hemispheres which represent
isovelocity surfaces.
As the blood accelerates toward the orifice velocity alaising
occurs,distinct red blue interface occurs at the boundary of
shells.
Velocity is equal to nyquist limit.
Surface area =2r²
Flow rate = 6.28 r² aliasing velocity
Flow rate =ERO velocity jet
![Page 27: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/27.jpg)
Index of LV contractility
Rate of LV pressure increase during early systole = dp/dt
Early mitral regurgitant velocity represents dp/dt as LA
Pressure varies little during isovolumic contraction.
Measuring the slope of the mitral regurgitation velocity.
Time interval between 1m/sec and 3m/sec
dp/dt = 32/time interval
Good correlation with cath data..
Normal dp/dt >1200mmhg /sec
![Page 28: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/28.jpg)
Ratio of pressure to flow.
SVR = MR velocity /LVOT TVI
SVR = Mean aortic pressure – RA Pressure /CO (cath)
SVR > 0.27 has 70% sensitivity and 77% specificity for SVR
>14 WU.
PVR = TR velocity/RVOT TVI* 10+0.16
![Page 29: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/29.jpg)
Workload on right ventricle
Derived by RHC – strong predictor of survival in patients with
pulmonary hypertension.
How much aggregate pulmonary artery will dilate with each
RV contraction.
PVCAP = SV/Pulse pressure of pulmonary artery
PVCAP = LVOT area* LVOT TVI / 4 (TR velocity² –PR
velocity ²)
![Page 30: Basics in echocardiography - an initiative in evaluation of valvular heart disease](https://reader030.fdocuments.in/reader030/viewer/2022032421/55a668321a28abbf668b460e/html5/thumbnails/30.jpg)