DIAGNOSTICS - Heart Diagnostic Imaging

Question 1

What can radiography of the heart be used to assess?

Answer 1

Heart size
Individual heart chamber enlargement
Evidence of congestive heart failure
Position of heart

Question 2

What are the two orientations that should be used to radiograph the heart?

Answer 2

Right lateral view
Dorsoventral (DV) view

Question 3

Identify the following features on this right lateral radiograph of the heart

Answer 3

Question 4

Identify the following features on this dorsoventral (DV) radiograph of the heart

Question 5

What size should a normal heart appear on a radiograph of a dog?

Answer 5

2/3 height of thorax
1/2-2/3 width of thorax
Take up 3-3.5 intercostal spaces

Question 6

What size should a normal heart appear on a radiograph of a cat?

Answer 6

2/3 height of thorax
1/2-2/3 width of thorax
Take up 2-3 intercostal spaces

Question 7

What can echocardiography be used to assess?

Answer 7

Internal structures of the heart
Myocardial function
Blood flow through the heart

Question 8

What is echocardiography?

Answer 8

Ultrasound of the heart

Question 9

What position should the patient be in for an echocardiogram?

Answer 9

Right followed by left lateral recumbency

Question 10

What is hypostatic congestion?

Answer 10

Hypostatic congestion is the partial collapse of the lung by the heart and mediastinum when an animal is in lateral recumbency

Question 11

How does the other lung compensate for hypostatic congestion?

Answer 11

The other lung will hyper inflate to compensate

Question 12

Why should you scan the heart from the lower thoracic wall when an animal is in lateral recumbency?

Answer 12

You should scan the heart from the lower thoracic wall when an animal is in lateral recumbency as the apex of the heart will partially collapse the lower lung, improving image quality and you will avoid imaging the upper hyper inflated lung which would usually obscure the image

Question 13

What is the best transducer to use for echocardiography?

Answer 13

Phased array transducer

Question 14

How does the lumen of the heart appear in an echocardiogram?

Answer 14

Anechoic (black) due to the blood in the lumen

Question 15

How does the cardiac muscle appear in an echocardiogram?

Answer 15

Echogenic (grey)

Question 16

How does the pericardium appear in an echocardiogram?

Answer 16

Hyperechoic (white) with an acoustic shadow and reverberations

Question 17

What is brightness (B-mode) echocardiography?

Answer 17

B-mode echocardiography produces a real-time grey-scale image of the heart.

Question 18

What are the two main standard views that should obtained during echocardiography?

Answer 18

Right parasternal view
Left parasternal view

Question 19

Which side of the heart is in the near field (top) of the ultrasound image in right parasternal views?

Answer 19

Right side of the heart

Question 20

Which side of the heart is in the far field (bottom) of the ultrasound image in right parasternal views?

Answer 20

Left side of the heart

Question 21

What are the three standard right parasternal short axis views of the heart that should be obtained during echocardiography?

Answer 21

Left ventricle
Mitral valve
Heart base

Question 22

Which standard view of the heart is represented in this image?

Answer 22

Right parasternal short axis view of the left ventricle

Question 23

Identify the labelled structures in this right parasternal short axis view of the left ventricle

Answer 23

Question 24

Which standard view of the heart is represented in this image?

Answer 24

Right parasternal short axis view of the mitral valve

Question 25

Identify the mitral valve in this right parasternal short axis view of the mitral valve

Answer 25

Question 26

Which standard view of the heart is represented in this image?

Answer 26

Right parasternal short axis view of the heart base

Question 27

Identify the labelled structures in this right parasternal short axis view of the heart base

Answer 27

Question 28

What are the two standard right parasternal long axis views of the heart that should be obtained during echocardiography?

Answer 28

Left atrium and ventricle Left ventricle and aorta

Question 29

Which standard view of the heart is represented in this image?

Answer 29

Right parasternal long axis view of the left atrium and ventricle

Question 30

Identify the labelled structures of this right parasternal long axis view of the left ventricle and atrium

Answer 30

Question 31

Why can only long axis views be obtained when an animal is in left lateral recumbency?

Answer 31

The apex of the heart is naturally located slightly to the left of midline, so when the patient is placed in left lateral recumbency, the apex moves closer to the thoracic wall than it does when the patient is in right lateral recumbency. This means that short axis left parasternal images would be difficult to visualise and thus only long axis views can be achieved

Question 32

What are the two standard left parasternal long axis views of the heart that should be obtained during echocardiography?

Answer 32

4-chamber 5-chamber

Question 33

Which standard view of the heart is represented in this image?

Answer 33

Left parasternal long axis 4-chamber view

Question 34

Identify the labelled structures of this left parasternal long axis 4-chamber view

Answer 34

Question 35

What is Time-Motion (M-mode) echocardiography?

Answer 35

M-mode echocardiography produces a single-dimensional image of the contraction or movement of the heart structures over time

Question 36

How is M-mode echocardiography performed?

Answer 36

M-mode is performed through manually placing a cursor line through the structures in the standard B-Mode image that you want to examine. The structures along the length of the cursor will then be displayed against time as a chart across the ultrasound screen

Question 37

Which are four useful measurements that can be obtained in M-mode echocardiography?

Answer 37

Shortening fraction Ejection fraction E-point to septal seperation (EPSS) Left atrial diameter

Question 38

What is the shortening fraction?

Answer 38

The shortening fraction is the fractional change between the left ventricular end-diastolic diameter and the left ventricular end-systolic diameter which can be used to assess contractile function of the ventricle

Question 39

Describe how the shortening fraction is calculated using M-mode echocardiography

Answer 39

To calculate the shortening fraction, a right parasternal short axis view of the left ventricle is used and the M-mode cursor is positioned so it bisects the left ventricle between the papillary muscles

Question 40

What is suggested by a reduced shortening fraction?

Answer 40

A reduced shortening fraction suggests reduced ventricular contractility

Question 41

What is suggested by an increased shortening fraction?

Answer 41

An increased shortening fraction would suggest compensatory hyper-contractility

Question 42

What is normal shortening fraction range in dogs?

Answer 42

25 - 45%

Question 43

What is normal shortening fraction range in cats?

Answer 43

30 - 55%

Question 44

What is E-point to septal separation (EPSS)?

Answer 44

E-point to septal separation (EPSS) is the distance between the mitral valve and the interventricular septum

Question 45

Describe how the E-point to septal separation (EPSS) is calculated using M-mode echocardiography

Answer 45

To calculate the end-point to septal separation (EPSS) a right parasternal short axis view of the mitral valve is used and the M-mode cursor is positioned so it bisects the mitral valve

Question 46

What is the normal E-point to septal separation (EPSS) value in a healthy animal?

Answer 46

The E-point to septal separation (EPSS) value should be no more than 7mm in a healthy animal

Question 47

What is indicated by a E-point to septal separation (EPSS) value above 7mm?

Answer 47

Indicative of left ventricular volume overload

Question 48

Describe how left atrial diameter is calculated using M-mode echocardiography

Answer 48

To calculate the left atrial size, a right parasternal short axis view of the heart base is used and the M-mode cursor is positioned so it bisects the left atrium and the aorta to compare the diameter of the left atrium and aorta at systole

Question 49

What is the normal ratio between left atrial diameter to aortic diameter in a dog?

Answer 49

1 : 1-1.4

Question 50

What is the normal ratio between left atrial diameter to aortic diameter in a cat?

Answer 50

1 : 1.2 - 1.7

Question 51

What is indicated by an increase in the ratio between left atrial diameter to aortic diameter?

Answer 51

An increase in the ratio between left atrial diameter and aortic diameter is indicative of atrial dilatation

Question 52

What is the function of doppler ultrasound?

Answer 52

Doppler ultrasound allows for the visualisation of the direction and velocity of blood flow through the heart

Question 53

What are the two types of doppler ultrasound

Answer 53

Colourflow doppler ultrasound Spectral doppler ultrasound

Question 54

How does colourflow doppler ultrasound depict blood flow through the heart?

Answer 54

Colourflow doppler depicts blood flow away from the transducer as blue, blood flow towards the transducer as red and turbulent blood flow as green

Question 55

How does spectral doppler ultrasound depict blood flow through the heart?

Answer 55

Spectral doppler ultrasound depicts blood flow as a graph which depicts blood velocity and direction