3. INTRODUCTION
Echocardiography is a choice investigation
for many cardiac abnormalities, part of the
reasons for this is how it allows for real time
images of the heart and how it functions.
4. DEFINITION
Echocardiography is an imaging modality
that uses piezoelectric waves to create
images of the heart
Echocardiography is basically a diagnostic
procedure whereby images of the heart are
produced using ultrasound
5. HISTORY
The origins of echocardiography date back to
the discovery of piezoelectricity in 1880”.
Ultrasound waves are created by
piezoelectric crystals inside the transducers.
The origins of clinical echocardiography date
back to the 1950s and credited to Carl
Helmuth Hertz and Inge Edler.
6. HISTORY
Their first paper entitled, ‘The Use of
Ultrasonic Reflectoscope for Continuous
Movements of the Heart Wall’ was published
in 1954.
The first academic course on cardiac
ultrasound, the first echocardiography
textbook, and even the term
‘echocardiography’ were developed in the
1960s and 1970s”
9. PRINCIPLE
Piezoelectric particles
Neither air nor bones are good transmission
media
Humans can hear sound waves with
frequencies ranging from 20 to 20,000 cycles
per second—that is, from 20 Hertz (Hz) to 20
kHz
Sounds above 20KHz is ultrasound
10. PRINCIPLE
Because wavelength (λ) times frequency (ƒ)
equals the propagation velocity (с), or λ × ƒ =
с, and the propagation velocity in the heart is
1540 m/sec, the wavelength for any
transducer frequency can be calculated as
follows:
λ (mm) = 1.54/ƒ (MHz)
13. VIEWS
Parasternal long axis
Parasternal short axis
Subxiphoid,transgastric view
Apical 5 chamber view
Apical 4 chamber view
Suprasternal view
11 recommended views by ACES on TEE
14.
15. The American College of Cardiology (ACC)
and the American Heart Association (AHA)
have recommended a set of minimum
knowledge and training requirements for the
performance and interpretation of
echocardiography, including a minimum
number of 150 performed and 300
interpreted examinations for level 2
competency in interpreting
echocardiography.
22. LEFT VENTRICULAR SYSTOLIC FUNCTION
Left ventricular ejection fraction(LVEF)
Stroke volume(SV)
Cardiac output and cardiac index(CO & CI)
Left ventricular percent fractional
shortening(%FS)
Mean velocity of circumferential fibre
shortening(mVcf)
23. LV SYSTOLIC FUNCTION
Global LV function can be assessed using
changes in the LV dimensions and volumes
between LV diastole and systole. The
recommended calculations are as follows:
Fractional shortening (FS)
Fractional area change (FAC)
Ejection fraction (EF)
Stroke volume (SV) and CO.
MAPSE
LVOT
24. LV SYSTOLIC FUNCTION
End-diastolic area measurement from
transgastric mid-papillary short axis for the
calculation of fractional area change
FAC = LVEDA − LVEDS/LVEDA × 100%.
Normal value - >35%
Severe LV systolic dysfunction - maximum
15%.
25. LEFT VENTRICULAR EJECTION FRACTION
It is the ratio of the left ventricular stroke
(LVSV)volume to left ventricular end diastolic
volume(LVEDV) expressed in percentage
Stroke Volume = LVEDV – LVESV
EF= (LVEDV – LVESV/ LVEDV) * 100%
26. CARDIAC OUTPUT & CARDIAC INDEX
CO is the volume of blood pumped out by the
left ventricle into the aorta per minute.
Cardiac index is CO divided by the body
surface area(BSA)
CO= SV*HR
CI= CO/BSA
27. LEFT VENTRICULAR PERCENT FRACTIONAL
SHORTENING(%FS)
It is an index of systolic funtion
Obtained by finding the difference btw left
ventricular diastolic (LVDd)and systolic
(LVDs), and dividing the difference by left
ventricular diastolic diastolic
dimension(LVDd)
%FS= (LVDd - LVDs/LVDd) * 100%
28. MEAN VELOCITY OF CIRCUMFERENTIAL FIBER
SHORTENING (MVCF)
It is an index of myocardial systolic
dysfunction obtained by correctting the %
fractional shortening with ejection time.
mVcf = (LVDd – LVDs /LDVd) * 1/ET
Ejection time is the time from the beginning of
the ejection flow from the left ventricle to the
end of it corresponding to the rising of the
edge of the carotid pulse to the dicrotic notch.
29. LEFT VENTRICULAR DIASTOLIC FUNCTIONS
These are particularly useful because
symptoms of heart failure may be seen in
patients with normal left ventricular wall
contraction
They include –
1. Left ventricular in flow velocity pattern or
transmural flow velocity pattern
2. Pulmonary venous flow velocity pattern
3. Flow propagation velocity(Vp) during rapid filling
4. Peak early diastolic velocity of mitral annulus(Ea,
E)
30. LV DIASTOLIC FUNCTIONS
LV End Diastolic pressure
Isovolumic Relexation Time
Aortic regurgitation CW Signal
MR CW Signal
Surrogates measurement
Mitral inflow velocities
tissue doppler annular signals
31. LEFT VENTRICULAR INFLOW VELOCITY
PATTERN OR TRANSMURAL FLOW VELOCITY
PATTERN (TMF)
The velocity waveform throug the mitral valve
from the left atrium to the left ventricle during
diastole
It is measured using pulsed doppler uss by
aligning the probe beam with the left
ventricular inflow tract
Deterioration of left diastolic function leads to
prolonged isovolumic relaxation time (IRT)
32. PULMONARY VENOUS FLOW VELOCITY PATTERN
In normal subjects, pulmonary venous flow
consists of
1. Anterograde during ventricular systole(S1, S2)
2. Anterograde flow during early ventricular
diastole(D wave)
3. Retrograde flow (atrial systolic wave: Ar-wave)
S2 wave is usually higher than D-wave.
S wave is attenuated, D wave is jncreased,
and Ar wave becomes longer when LVEDP,
left atrial pressure and PAWP rise
33. FLOW PROPAGATION VELOCITY(VP) DURING
RAPID FILLING PERIOD
It is the slope of the line along the peak flow
velocity or the slope oof the initial aliasing
border.
It correlates well with peak negative ie
dP/dt and time constant which are indices of
left ventricular relaxation in direct
proportions.
34. PEAK EARLY DIASTOLIC VELOCITY OF MITRAL
ANNULUS
Mitral annulus(left ventricular post wall, lat
wall, or IV septum)
It is sensitive to left ventricular relaxation and
not easily affected by preload compared to the
E wave of the ventricular inflow velocity
pattern .
It doesn’t show pseudonormalization
Values though are region dependent and
values in a region of the ventricle affected by
MI is not representative of the whole ventricle
35. INDEX FOR BOTH SYSTOLIC AND DIASTOLIC
FUNCTIONS
Tei Index
It is proven to be very useful in clinical setting since
most other indices evaluate either of systolic or
diastolic functions while most patients have a degree
of both.
It assess the global functioning of the systolic and
diastolic function
If “a” is the time from start to end of transmitral or
tricuspid blood flow
And “b” is the time from start to end of aortic or
pulmonary blood flow as measured by pulse doppler.
36. CONTD
Tei index is a – b /b
Normal values : 0.28+/- 0.04 in rt ventricle,
0.38+/- 0.04 in left ventricle.
If value is 0.4 in rt or 0.45 or higher in lt, it is
regarded as abnormal.
37. LVH
The LV mass, estimated from standardly
measured dimensions, was increased
(greater than 200 g)
38. The role of Cardiac indices in clinical practice
in cardiology has seen improvements and
more research is still being done, which are
sure to lead to better discoveries and patient
management in the nearest future
40. REFERENCE
Standard measurement of cardiac function
indexes - Terminology and diagnostic criteria
committee in Japan society of ultrasound in
medicine, 2006
Hendrickson RG, Dean AJ, Costantino TG.
A Novel use of ultrasound in pulseless electrical
activity: The diagnosis of an acute abdominal
aortic aneurysm rupture. J Emerg
Med.2001;21:141-144.
Kircher BJ, Himelman RB, Schiller NB.
Noninvasive estimation of right atrial pressures
from the inspiratory collapse of the inferior vena
cava. Am J Cardiol.1990;66:493-496.
