Veterinary Diagnostics canine Echocardiography

1. ECHOCARDIOGRAPHY
Submitted to
Dr Manjunatha D R
HOD
Dept Of TVCC
Veterinary College Hassan
Submitted By
Venkatesh S M
Jr.MVSc-VSR
Veterinary college Hassan

2. DEFINATION
• Interaction between ultrahigh frequency sound waves and
the heart allows the depiction of cardiac morphology,
information on the movement of myocardium and valves, and
blood flow within the heart.
• Also called as transthoracic cardiac ultrasonography.
• Provides high quality images of the heart,great vessels &
paracardiac structures.
• It has replaced invasive techniques like cardiac catheterization.

4. ECHOCARDIOGRAPHY THORACIC RADIOGRAPHY
No sedation Mild or no sedation
Detailed,dynamic image of cardiac chambers
and great vessels in real time
Image of cardiac silhouette
Examination of heart from multiple imaging
planes
Examination of cardiac silhouette limited to 4
views in two orthogonal planes
Information on cardiac function and
intracardiac blood flow
No information on cardiac function or
intracardiac blood flow
Evaluation of heart possible in presence of
pleural effusion
Evaluation of cardiac silhouette impaired by
pleural effusion
Pneumothorax, dyspnoea and tachypnoea may
hinder ultrasonographic examination
Dyspnoea and tachypnoea may result in
movement blur on radiographs
Does not provide information on lung diseases
or presence of pulmonary oedema
Provides critical information on lung
disease,most importantly pulmonary oedema
& pulmonary vascular diseases
Expensive and requires ultrasound system
equipped with dedicated software and
transducers
Available in most veterinary practices and
inexpensive
Safe for the patient and operator Exposes patient and personnel to ionizing
radiation

5. Instruments/equipments
Consist of
• Echo table/ cut out tables
• Probes/transducers
• Coupling media
• Control panel and display monitor

6. Cut out tables for cardiac echo

7. Probes/transducers
• Function is to send and receive signals.
Parts of transducer
A. Plastic housing
B. Acoustic insulator
C. Backing block
D. Electrodes
E. Piezo-electric crystals
(lead zerconate titanate)

8. Types of probes
• Linear probe: crystals in rows,rectangular beam.
• Curvilinear probe:crystals in curvilinear manner, nearly pie
shaped beam.
• Phased array probe: one or more crystals move or oscillate to
produce pie shaped beam.

9. Types of probes

10. Selection of probe
• Depending upon type of animal, organ & depth of organ
• 7-8 MHz for <7 kg
• 5 MHz for most dogs(medium sized)
• 3-3.5 MHz for >50 kg
• Higher frequency-shorter wavelength-better resolution-low
penetration
• Lower frequency-deep penetration-less resolution
• Higher frequency-less depth
• Lower frequency-more depth

11. Coupling media
• Coupling gel or KY jelly
• Mineral oil usage is avoided as it causes scruff and damage
transducer head.
• Coupling gel should thoroughly removed after examination-
irritation to skin if allow to dry on skin.

12. Control panel and display monitor
• Basic set of controls
• Power: controls intensity of sound output
• Near gain,slope delay,slope rate: alter amplification of returning
echoes.
• Depth: determine the depth of US image.
• Freeze: real time image can be temporarily frozen.

13. Principle of echocardiography
• Sound waves travels in a pulse and when it is reflected back it
become the echo.
• So it is pulse-echo principle used for ultrasound imaging.
• When any form of energy is applied to a quartz crystals it
vibrates to produce waves.
• This waves strikes the various tissues and is reflected back to
the quartz crystals, which in turn produces a corresponding
electric current.

14. • This current is further processed by the machine, to be
displayed as images.
• The image is displayed in various shades of grey depending on
tissue density

15. Echocardiographic technique
• Patient preparation
• Position of animal on echo table
• Probe placement
• Image orientation
• Interpretation

16. Patient preparation
• Usually performed without sedation.
• Hair coat is clipped b/w costochondral junction and sternum on
both sides.
• For thin hair coat animals,hair clipping is not necessary.

17. Placement of animal
• Left or right lateral recumbency on a table allowing transducer
placement.
• Also examined in standing, sitting or sternal position.
• Patients in heart failure with respiratory distress may not
tolerate lateral recumbency and the alternative positions may
be used.

18. Transducer placement
• Acoustic window: Transthoracic echocardiographic images can
be obtained only from regions where the heart contacts an
intercostal region. This region is often small & is called a
window.
• For right parasternal window: 3-6 ICS
• For left parasternal window: b/w 5 &7 ICS(apical view)
: at 3 or 4 ICS(cranial view)

19. Image orientation & interpretation
• All probes have reference mark(ridge/light/raised dot)
• Reference symbol is displayed on the right side of the sector

22. 2 D ECHO
• 2D echo uses transducers that transmits multiple beams of
sound in the form of sector/pie.
• Obtain standard parasternal long and short axis view, subcostal
view.
• Cardiac chamber,valve and great vessel anatomy assessment.
• Cardiac chamber size, systolic function of ventricles can be
evaluated.
• Detection of pericardial effusion and cardiac masses.

24. 2D
Echo
Rt.Parasternal
axis
Long Axis
4 Chamber
view
5 Chamber
view
Short axis
M.V level
Aortic valve level
P.A level
Lt.Apical
4 Chamber
view
5 Chamber
view
Tricuspid .V
level

25. Long axis view short axis view

27. parasternal 4 chamber long axis view

28. Long axis view short axis view

30. Parasternal 5 chamber long axis view

31. Short axis planes
PULMONARY VALVE
Aortic valve
Mitral valve
Lt.ventricle chordae tendinae
Papillary muscle

34. Parasternal short axis at papillary muscle level

35. Parasternal short axis at mitral valve level

36. Parasternal short axis at aortic valve level

37. Parasternal short axis at pulmonic valve level

39. Apical 4 chamber view

40. Apical 5 chamber view

41. M mode echo
• M-mode echocardiography uses a single, thin ultrasound
beam rather than a fan-shaped beam.
• Used to record and analyse thickness and motion of the
soft tissue structures of the heart (heart chamber walls,
valves, vessels).
• The distance of individual structures from the transducer is
displayed on the vertical axis and time is displayed on the
horizontal axis.
• M-mode examinations are carried out almost from the right
parasternal approaches.

43. M mode at ventricular level

46. M-mode- mitral valve
•Analysed for rate of opening
and closing .
•Indicator of Lt.V filling
&function.
•EPSS-Very consistent and
popular mitral valve
measurement .
•EPSS –Shortest distance from
the E point of the MV to the
ventricular septum.
•Normal Dog EPSS- <7.7

48. M mode at aorta

49. Measurements
• LV diameter-through M-mode
• LV wall thickness
• Lt. Atrial & Aortic dimensions – M
mode & 2D measures
Chamber
dimensions
• Lt.V. Fractional shortening (FS%)
• E point Septal Separation (EPSS)
• End-Systolic Volume Index(ESVI)
• Ejection fraction( EF%)
• Systolic Time Intervals
Systolic function
• Doppler Echo-Choice for evaluation
Diastolic function

51. Left ventricular diameter
• Typically measured –M-mode
• Leading edge to leading edge.
• LVDd- Diastole reading.
• LVDs –Systole reading.

52. Left ventricular wall thickness
• Best measured -2D images.
• More important –Cats(Feline myocardial diseases)

53. Left atrial diameter
• LA size can be measured
– M-mode- At Aortic valve level.
– 2D short axis-Aortic valve.
– 2D long axis-4 chamber view.
• M-mode - LA: Ao = 1
• Short axis- LA: Ao < 1.6
• Long axis - LA: Ao <2.5

54. Fractional shortening
• FS –Common Echo index of
systolic function.
• FS % = (LVDd-LVDs) x 100
• LVDd.
• Mean FS % range – 25-40 %
– >30% in the dog
– >40% in the cat
– >45% if MR is
compensated

55. EPSS
• M-mode measure – at Mitral valve.
• Distance between
&Peak opening of
• Indicator of .
• Normal dog EPSS-
• Range in giant breeds –

56. End systolic volume index(ESVI)
• Measure- 2D image(Rt.Para
Sternal long axis).
• ESVI = End Systolic volume
• Body surface area.
• EDVI = End Diastolic volume
• Body surface area.
• Normal ESVI – 30ml/m2
V = 0.85 x A2/L
Body surface area (BSA) in square
meters = K × (body wt in grams2/3) × 10-4
K = constant (10.1 for dogs and 10.0 for cats)

57. EJECTION FRACTION
• Calculation of Lt. Ventricular Volume is essential.
• EF % = ( End Diastolic .Vol - End Systolic.Vol ) X 100
End Diastolic. Vol
• Normal EF % in dogs – 50-65%
• EF –Squeezing ability of the heart .
• EF% = Stroke Volume /End diastolic volume

58. M mode echo calculation parameters
End diastolic volume EDV= 7 LVIDd3
2.4 + LVIDd
End systolic volume ESV= 7 LVIDs3
2.4 + LVIDs
Stroke volume SV = EDV - ESV
Cardiac output CO = SV x heart rate
Fractional shortening FS = LVIDd - LVIDs
LVIDd
Ejection fraction EF = SV
EDV
Percent of septum thickening PST = Std -Sts
STd
Percent of posterior wall
thickening
PWT = LVPWd - LVPWs
LVPWd

59. Doppler echo
• This modality allows detection and analysis of moving blood
cells or myocardium.
• It tells us about the direction, velocity, character, and timing
of blood flow or muscle motion.
• The hemodynamic information provided by Doppler
echocardiography allows definitive diagnosis in most cardiac
examinations.

60. Doppler tracing
• The change in frequency between sound that is transmitted and
sound that is received is the Doppler shift
• The Doppler-derived frequency shift (fd) is equal to reflected
frequency minus transmitted frequency, therefore, objects
moving toward the source result in positive frequency shifts
while objects moving away from the source result in negative
frequency shifts.

61. • Gate -The site for Doppler flow interrogation is selected by the
examiner and is represented on the Doppler display as a line
(baseline).
• Positive frequency shifts (flow moving toward the transducer)
produce waveforms up from the baseline while negative
frequency shifts (flow moving away from the transducer)
produce downward deflections on the Doppler tracing .
• These images are called spectral tracings. Velocity scale is
displayed along the side of the spectral image. The velocity
range is split between the baseline.

62. Mitral flow aortic flow

63. Color flow doppler
• Color-flow Doppler is a form of pulsed-wave Doppler.
• Frequency shifts are encoded with varying hues and
intensities of colour.
• Flow information is very vivid, and detection of abnormal
flow is easier with color-flow Doppler although
quantitative information is limited.

64. • Color-flow doppler involves a sector
filled with many lines of
interrogation,contain multiple
gates,sends information back to the
transducer.
• This frequency shift information is sent to
a processor, which calculates the mean
velocity, direction, and location of blood
cells at each gate.
• color is assigned to each gate based on
direction and velocity of flow.

65. Bart mapping
• Blood flow away from probe – Blue to
white
– Deep blue – Slower flow
– White – Faster flow.
• Blood flow towards probe – Red to
Yellow.
– Deep red – Slower flow rate
– Bright yellow – Faster flow
• No flow – Black color

66. Color flow doppler

67. Interpretation
Mitral regurgitation normal
Aortic regurgitation
normal

68. Ventricular septal disease

69. Tissue doppler imaging
• Reflection of sound from blood is high frequency and low
amplitude.(normal blood flow is<200cm/sec)
• TDI uses low frequency high amplitude sound to record
myocardial velocity during systole and diastole.
• Pulse wave tissue doppler can be obtained in real time
by placing gate over a portion of myocardium and record
the positive and negative frequency shift.

70. TDI

71. Transesophageal echocardiography
• When there is difficulty to perform transthoracic
echocardiography due to lung interference and obesity in
some patient, it is used.
• Ultrasonic transducers mounted at the tip of flexible, steerable
endoscope to image the heart & great vessels from within the
esophagus.
• Useful in examination of pulmonic valve anatomy in dogs with
pulmonic stenosis & other heart base lesions.

72. Transesophageal echocardiography

73. REFERENCES
• Veterinary echocardiography-JUNE A. BOON.
• Small animal diagnostic ultrasound-NYLAND/MATTOON.
• BASAVA MANUAL of canine and feline ultrasonography.

74. THANK YOU

87. More accurate velocity velocity is underestimated