Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cardiology > Imaging of the cardiovascular system > Flashcards

Imaging of the cardiovascular system Flashcards

1
Q

Indications for CV imaging

A

Cough

Dyspnoeas: tachypnoea, orthopnoea

Exercise intolerance

Murmurs heard on examination

Pre-treatment checks (doxorubicin, pre-anaesthesia is disease suspected)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Imaging techniques for CV system

A

Thoracic radiography
Echocardiography
Angiography
Scintigraphy
Computed tomography
Pneumopericardiography (rarely used)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which radiographic projections are best for imagng the heart?

A

The dorsoventral and right lateral projections are best because the heart lies in a more consistent position.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Contrast techniques for imaging CV system

A

Angiocardiography

Pneumopericardiography (following drainage of a pericardial effusion (rarely used)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What can thoracic radiographs provide information about (CV)?

A

Heart size
Cardiac chamber enlargement
Pulmonary vasculature changes
Lung patterns associated with cardiac disease
Great vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Normal heart size in dogs

A

Varies greatly between different breeds of dog

deep-chested breeds the heart is tall, narrow and upright whereas in barrel-chested breeds it is globular

Lateral
- width 2.5 - 3.5 times intercostal space
- height two-thirds height of thoracic cavity
- short axis + long axis = 9.7 ± 0.5 thoracic vertebral body lengths in most breeds

Dorsoventral
- width two-thirds of width of thoracic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Normal heart size in cats

A

Lateral - short axis dimension is 2 intercostal spaces
○ vertebral scale system (VHS) 7.5 ± 0.3 vertebral body lengths
○ height two-thirds height of thoracic cavity

Dorsoventral - width two-thirds width of thoracic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Normal variations of heart size on radiograph

A

Due to technique
○ Cardiac cycle
○ Respiratory cycle

Breed related in dogs
○ Globoid in retrievers
○ Elongated in … ?

Cats: older cats can have a ‘redundant aorta’
○ 30-40% of cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Position of individual heart chambers on lateral radiograph

A

cranial and caudal cardiac waists
right chambers cranial
left chambers caudal

12-2 o’clock: left atrium
2-5 o’clock: left ventricle
5-9 o’clock: MPA and right auricular appendage
10-11 o’clock: aortic arch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Position of individual heart chambers on DV radiograph

A

11 to 1 o’clock - the aortic arch
1 to 2 o’clock- the pulmonary artery
2 to 3 o’clock - the left auricular appendage
2 to 5 o’clock - the left ventricle
5 to 9 o’clock - the right ventricle
9 to 11 o’clock - the right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pulmonary vasculature on radiography

A

arteries and veins should be of similar size and run on either side of the bronchi

arteries are dorsal and the veins ventral in the lateral view

diameter of the cranial lobe vessels should be smaller than the proximal third of the 4th rib

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

CdVC on radiographs

A

0.75 ± 0.13 vertebral lengths.

CdVC: aorta < 1.5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cranial mediastinum on radiograph

A

In dogs, normally no wider than 1-1.5 times the width of vertebral column, except in brachycephalic breeds where it is often larger. In cats, it is normally no wider than the vertebral column.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Concentric hypertrophy

A

Increased systolic pressure (pressure overload)

Ventricular wall becomes thicker

Chamber size remains the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Eccentric hypertrophy

A

Increased diastolic pressure and volume (volume overload)

Dilatation

Lumen size increases

Ventricular size initially the same, then thins

Eccentric is more easily seen radiographically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Left sided cardiomegaly on lateral radiograph

A

Taller heart resulting in tracheal and bronchial elevation

Splitting of the mainstem bronchi - left dorsal to right

Caudal border straighter and more upright

Left atrium bulges caudiodorsally

Loss of caudal cardiac waist and elevation of the caudal vena cava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Left-sided cardiomegaly in DV radiograph

A

Increased width of the cardiac silhouette

Rounding of left ventricular border

Heart apex may be displaced to the right

Enlarged left auricular appendage 2 to 3 o’clock

Dilated LA superimposed on cardiac silhouette

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Left atrial enlargement on radiograph

A

Straightening caudo-dorsal cardiac waist

Dorsal deviation of the mainstem bronchi on DV

Elevation of the left caudal mainstem bronchus (separation of the two mainstem bronchi on lateral)

Increased height of the heart

Enlargement of the pulmonary veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Left ventricle enlargement on radiograph

A

Hypertrophy = can be radiographically normal

Dilation:
○ Tracheal elevation (entire trachea)
○ Loss of normal dipping of the carina
○ Straight caudal border of the heart
○ In DV view: increased length of the cardiac silhouette, can see rounding of the apex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Secondary features of left sided cardiomegaly on radiographs

A

Engorgement and tortuosity of pulmonary veins compared to the arteries

Patchy increase in lung density particularly in perihilar region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Right-sided cardiomegaly on lateral radiograph

A

Heart is enlarged craniocaudally

Rounding of the cranial border

Increased sternal contact

Loss of cranial cardiac waist

Elevation of cranial lobe bronchi and vessels

Elevation of trachea just cranial to carina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Right-sided cardiomegaly on DV radiograph

A

Increased width of heart

Rounding of right cardiac border, reversed ‘D’ shape

Heart apex may be displaced left

23
Q

Right ventricle enlargement on radiograph

A

Often over-diagnosed

Rare

Reverse D shape

Elevation of the apex from the sternum on the left lateral view

Elevation of the trachea without loss of the dipping of the trachea

Often concurrent with left ventricular dilation (DCM cases)

24
Q

Right atrial enlargement on radiograph

A

Uncommon in isolation

Focal bulge on cranial aspect of the cardiac silhouette

Deviation of the trachea at the focal bulge

25
Q

Secondary features of right sided cardiomegaly on radiograph

A

Engorgement and enlargement of CdVC.

CdVC: Ao > 1.5

CdVC: vertebral length > 1.30

CdVC: rib 4 > 3.50

Hepatic enlargement

Ascites

26
Q

Generalised cardiomegaly on radiograph

A

Radiological signs of both left- and right-sided enlargement will be present.

Globoid appearance of the heart, more valentine shaped heart in cats

Enlargement of the cardiac silhouette in all chambers

Radiographic signs of both left and right sided enlargement

Signs of congestive heart failure
○ Pulmonary oedema
○ Hepatomegaly
○ Ascites

27
Q

Pericardial effusion causes

A

neoplasia (haemangiosarcoma, heart base tumour, mesothelioma)

idiopathic,

left atrial rupture,

haemorrhage,

infection,

chronic uraemia

right-sided heart failure.

In cats, cardiomyopathy and FIP are most commonly involved.

28
Q

Radiological signs of pericardial effusion

A

Gross enlargement of cardiac silhouette

Appears globular in both views

Sharp borders, effacement of the cardiac waists

No individual chamber enlargement identified

Under perfusion of the lung fields usually

Evidence of right sided heart failure can be present

Right-sided failure due to cardiac tamponade – ascites can be seen in the abdomen

Pleural and mediastinal fluid may be present

Pericardiocentesis followed by pneumopericardiography can be used for differential diagnosis, although ultrasound is now the method of choice

29
Q

Echocardiography signs of pericardial effusion

A

Echolucent space between the epicardium and pericardium

There may be abnormal cardiac motion

Fluid space is greatest at the cardiac apex

Fluid may contain echodense material - fibrin, clots or tumour

30
Q

Differentials for left sided cardiomegaly

A

Mitral incompetence
§ Mitral dysplasia
§ Chronic valvular disease
§ Endocarditis

Sub-aortic stenosis

Dilated cardiomyopathy

31
Q

DIfferentials for right sided cardiomegaly

A

Tricuspid incompetence
§ Tricuspid dysplasia
§ Chronic valvular disease

Pulmonic stenosis

Tetralogy of fallot

Chronic pulmonary disease

Heartworm disease

32
Q

Differentials for generalised cardiomegaly

A

Chronic valvular disease

Patent ductus arteriosus

Ventricular septal defect

Dilated cardiomyopathy

Chronic anaemia

33
Q

Pericardial cysts

A

Rare.

They occur in the costophrenic angles and may be caused by incarcerated omentum or abnormal development of mesenchymal tissue during fetal life.

The history, clinical signs, pathophysiology and diagnosis are similar to those of pericardial effusion.

34
Q

Peritoneo-pericardial diaphragmatic hernia

A

Congenital defect with abdominal viscera displaced into pericardial sac resulting in gastrointestinal or respiratory signs, which can occur at any age.

Weimaraners over-represented.

35
Q

Radiological signs of Peritoneo-pericardial diaphragmatic hernia

A

Large round cardiac silhouette with dorsal displacement of the trachea

Enlarged cardiac silhouette merges with the diaphragm - the dorsal peritoneopericardial mesothelial remnant has been shown to be an aid to diagnosis in the cat

Different densities within the cardiac silhouette

Gas-filled intestine may be superimposed on cardiac shadow

‘Empty abdomen’

Barium can be used to confirm diagnosis

Sternal abnormalities

Absence of radiographic signs of heart failure

Incidental finding

36
Q

When is reduced cardiac size seen?

A

Microcardia is seen in hypovolaemic shock and hypoadrenocorticism.

37
Q

Radiological signs of reduced cardiac size

A

Heart size is reduced in all directions

Apex may be raised from the sternum

Cardiac shape appears triangular

Hyperlucent lung fields due to pulmonary undercirculation

Caudal vena cava reduced in size

38
Q

Pulmonary circulation on DV radiograph

A

Artery lateral to the vein

Artery = vein in diameter

Diameter < diameter 9th rib

38
Q

Pulmonary circulation on lateral radiograph

A

Artery dorsal to vein

Diameter <proximal third of 4th rib

Artery = vein in size roughly

39
Q

Radiological signs of pulmonary undercirculation

A

Lung field more lucent

Pulmonary arteries smaller than normal and smaller than corresponding pulmonary vein.

40
Q

Aetiology of pulmonary undercirculation

A

Right to left shunting (eg. tetralogy of Fallot)

Pulmonic stenosis

Hypovolaemic shock (+ microcardia)

Hypoadrenocorticism (+ microcardia)

41
Q

Differential diagnoses when radigraphic signs of pulmonary undercirculation

A

Emphysema, overinflation, overexposure

42
Q

Aetiology of pulmonary overcirculation

A

Left to right shunting (eg. PDA, VSD)- both arteries and veins enlarged

Congestive heart failure - veins > arteries

Heartworm disease (Dirofilaria immitis, Angiostrongylus vasorum) arteries > veins

Iatrogenic fluid overload - both arteries and veins enlarged

43
Q

Radiological signs of pulmonary overcirculation

A

Increased vascular pattern

Pulmonary arteries and veins larger than normal

44
Q

Differentials of pulmonary overcirculation signs on radiograph

A

Underexposure, expiratory radiograph

45
Q

Technique for echocardiography

A

Should be imaged from the right and left sides.

Occasionally suprasternal and subcostal views are also required.

A small area of hair should be clipped extending for several intercostal spaces over the palpable apex beat of the heart on each side of the thorax, usually i/c space 3 to 6.

A generous quantity of coupling gel is applied to the thorax to eliminate air

2-D (B-mode - 2D real time), M-mode and Doppler studies may then be undertaken.

Simultaneous ECG is essential for producing accurate timings within the cardiac cycle.

Contrast echocardiography can be performed by injecting a bolus of contrast into a peripheral vein while imaging the heart.

Saline, blood and Gelofusion have been used after agitation to produce microbubbles.

The left cardiac chambers are not normally opacified as the microbubbles do not pass through the pulmonary circulation.

46
Q

2D echocardiography assessment

A

Provides anatomical and functional information.

A systematic approach is essential to ensure nothing is missed.

Assessment includes:
* Overall size
* Cardiac motion
* Normal anatomy
* Atrioventricular valves
* Semilunar valves
* Chamber size
* Great vessels

47
Q

Right parasternal long axis view (echocardiography)

A

(3rd-6th i/c space)

left ventricle apex and mitral valve

LV apex, LV outflow tract, aortic valve and proximal ascending aorta

left atrium and pulmonary veins

interventricular septum, LV outflow, aortic valve, mitral valve and left ventricular free wall (a plane between previous view and next)

aortic annulus, valve cusps and sinuses of Valsalva

Display with cardiac apex to the left and the base (atria or aorta) to the right

48
Q

Right parasternal short axis view (echocardiography)

A

(3rd-6th i/c space)

LV, high papillary muscle level

chordae tendinae of the left ventricle

mitral valve

aortic root and valve

Display with cranial part of the image (RV outflow) to the right with the right heart encircling the LV and aorta clockwise

49
Q

Left parasternal apical long axis view (echocardiography)

A

(5th-7th i/c space)

LV, mitral valve and left atrium, with slight counterclockwise rotation the LV outflow can be seen

Display with LV apex to the left and LA or aorta to the right

LV, LA, RV, and RA (four chamber view)

Display with left heart to the right and the right heart to the left

50
Q

Left parasternal long axis view (echocardiography)

A

(3rd-4th i/c space)

LV outflow tract, aortic valve and ascending aorta

Display with LV apex to the left and aorta to the right

right ventricular inflow and tricuspid valve, angle beam ventrally

RV outflow tract, pulmonary valve and pulmonary artery, angle beam dorsally

51
Q

Left parasternal short axis view (echocardiography)

A

right ventricular inflow and outflow with short axis view of aorta

Display with right heart encircling the aorta clockwise (RV inflow to the left, RV outflow and PA to the right

52
Q

M-mode echocardiography

A

Allows measurement of chamber size and wall thickness and provides characterisation and timing of motion, relative to the ECG, during the cardiac cycle.

Correct alignment of the M-mode cursor is required in both the long and short axis planes for accurate and reproducible measurements to be made.

The left ventricular dimensions should be obtained when the ultrasonic beam is directed between the papillary muscles in the short axis view at the level of the chordae tendineae.

M-mode measurements are affected by body weight, breed, heart rate, age and physical training.

Measurements from the M-mode tracing are made from leading edge to leading edge.

53
Q

Doppler echocardiography

A

Assess:
○ Quality of flow
○ Velocity of flow
○ Pressure gradients
○ Cardiac output
○ Blood flow

A few diagnoses
○ Valvular stenosis
○ Valvular regurgitation
○ Intracardiac shunts

Cardiology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions