Download PowerPoint - Cardiovascular Radiology

Thoracic Radiology
Wendy Blount, DVM
Nacogdoches TX
Thoracic Rads - Normal
Review of thoracic radiographs – 7 Steps
1. Skeletal
– Spine, front limbs, ribs, sternum
2. Cranial abdomen
3. Airways, Lung fields
4. Great vessels
– Aorta, pulmonary arteries, cranial & caudal vena cava
5. Smaller vessels
– Internal thoracic arteries, pulmonary lobar a & v,
brachiocephalic trunk, left subclavian artery
6. Cardiac silhouette
– Vertebral heart score, bulges
7. Left Heart Failure? Right Heart Failure?
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Comparing heart size to lung field size
doesn’t work
– Dogs of different conformation have different
ratios of heart size to lung size
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Comparing heart size to lung field size
doesn’t work
– Dogs of different conformation have different
ratios of heart size to lung size
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Comparing heart size to lung field size
doesn’t work
– Dogs of different conformation have different
ratios of heart size to lung size
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Comparing heart size to lung field size
doesn’t work
– Dogs of different conformation have different
ratios of heart size to lung size
– Lung field size changes with the breathing cycle
– Abdominal fat pushes the diaphragm cranially
– Thoracic fat makes lung fields appear smaller
• Comparing heart size to vertebral size
works better
– Vertebral heart score
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
– Pericardial fat
– Pericardial effusion
– Peritoneopericardial diaphragmatic hernia
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
– Pericardial fat
– Pericardial effusion
– Peritoneopericardial diaphragmatic hernia
Thoracic Rads - Normal
Why is it so difficult to evaluate cardiac
and chamber size on radiographs?
• Things can make the heart look bigger
–
–
–
–
Pericardial fat
Pericardial effusion
Peritoneopericardial diaphragmatic hernia
Oblique positioning on VD/DV can make right
heart look bigger
• MYTH - “increased sternal contact”
means right heart enlargement
Thoracic Rads - Normal
Thoracic Rads - Normal
Thoracic Rads - Normal
Normal cats change with age
• Long axis of the heart is more
horizontal in old cats (40%)
• Aortic bulge develops (30%)
– Not due to hypertension or hyperthyroidism
– At the aortic isthmus
– Cardiac measurements in young & old cats are
the same, despite these conformational changes
in the thorax
Thoracic Rads - Normal
5.0 + 4.8 = 9.8
Vertebral Heart Score
Thoracic Rads - Normal
Vertebral Heart Score
• Measure heart long axis
– carina to the apex
• Measure heart short axis
– Widest point perpendicular to length
•
•
•
•
Count vertebrae from cranial aspect T4
Add together
Dogs – normal 8.5-10.5
Cats – normal 7-8
Thoracic Rads - Normal
Heart Chambers – VD/DV - Left
LV - Left Ventricle
AV - Aortic Valve (AoV)
AA - Ascending Aorta
DA - Descending Aorta
Thoracic Rads - Normal
Heart Chambers – VD/DV - Left
LV - Left Ventricle
AV - Aortic Valve (AoV)
AA - Ascending Aorta
DA - Descending Aorta
LA – Left Atrium
Thoracic Rads - Normal
Heart Chambers – VD/DV - Left
Thoracic Rads - Normal
Heart Chambers – VD/DV - Right
PV
RV - Right Ventricle
PV - Pulmonic Valve
MPA - Main Pulmonary Artery
RPA - Right Pulmonary Artery
LPA - Left Pulmonary Artery
Thoracic Rads - Normal
Heart Chambers – VD/DV - Right
Thoracic Rads - Normal
Heart Chambers – VD/DV – Clock Face
• Aorta 12-1 o’clock
• LV 3-6 o’clock
Thoracic Rads - Normal
Heart Chambers – VD/DV – Clock Face
• Aorta 12-1 o’clock
• MPA 1-2 o’clock
• LV 3-6 o’clock
• RV 7-9 o’clock
Thoracic Rads - Normal
Heart Chambers – VD/DV – Clock Face
• Aorta 12-1 o’clock
• MPA 1-2 o’clock
• LV 3-6 o’clock
• RV 7-9 o’clock
• LA has to be really
big to see on K9 VD
Thoracic Rads - Normal
Heart Chambers – VD/DV – Clock Face
• Aorta 12-1 o’clock
• MPA 1-2 o’clock
• LV 3-6 o’clock
• RV 7-9 o’clock
• LA has to be really
big to see on K9 VD
• RA 9-12 o’clock
Thoracic Rads - Normal
Heart Chambers –
Lateral – Left
•
•
•
•
•
•
•
LA – Left Atrium
MV – Mitral Valve
LV – Left Ventricle
AV – Aortic Valve (AoV)
SV – Sinus of Valsalva
AAo – Ascending Aorta
BCT – Brachiocephalic
Trunk
• LS – Left Subclavian a.
Thoracic Rads - Normal
Heart Chambers –
Lateral – Right
•
•
•
•
RA – Right Atrium
RAu – R Auricle
RV – Right Ventricle
MPA – Pulmonary a.
Thoracic Rads - Normal
Heart Chambers –
Lateral – Right
•
•
•
•
•
•
•
•
RA – Right Atrium
RAu – R Auricle
RV – Right Ventricle
MPA – Pulmonary a.
RVOT – RV Outflow
PV – Pulmonic Valve
RPA – R Pulmonary a.
LPA – L Pulmonary a.
Thoracic Rads - Normal
Heart Chambers – Lateral – Clock Face
•LA (caudal waist) –
12-3 o’clock
•LV - 2-6 o’clock
Thoracic Rads - Normal
Heart Chambers – Lateral – Clock Face
•LA (caudal waist) –
12-3 o’clock
•LV - 2-6 o’clock
•RV - 6-9 o’clock
•MPA – 10-11 o’clock – bulge at 1-2 o’clock
Thoracic Rads - Normal
Heart Chambers – Lateral – Clock Face
•LA (caudal waist) –
12-3 o’clock
•CdVC – 2 o’clock
•LV - 2-6 o’clock
•RV - 6-9 o’clock
•RAu – 9 o‘clock
•RA not easily seen
on the lateral view
•CrVC – 10 o’clock
•MPA – 10-11 o’clock – bulge at 1-2 o’clock
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
5.8 + 5.8 = 11.6
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel - coughing
• 1-2 - Skeletal, Cranial abdomen
– Mineralized costal arch
• 3 - Airways, Lung fields
– Mild tracheal elevation, Mild perihilar edema
• 4 - Great vessels
– enlarged caudal vena cava
• 5 - Smaller vessels
– enlarged cranial pulmonary lobar veins
• 6 - Cardiac silhouette
– Generalized cardiomegaly, enlarged LA
• 7 – RHF? LHF?
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel - coughing
• Skeletal, Cranial abdomen
– No abnormalities noted
• Airways, Lung fields
– Mild perihilar edema
• Great vessels
– enlarged caudal vena cava
• Smaller vessels
– enlarged pulmonary lobar veins
• Cardiac silhouette
– Generalized cardiomegaly, enlarged LA
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel - coughing
• Skeletal, Cranial abdomen
– No abnormalities noted
• Airways, Lung fields
– Mild perihilar edema
• Great vessels
– enlarged caudal vena cava
• Smaller vessels
– enlarged pulmonary lobar veins
• Cardiac silhouette
– Generalized cardiomegaly, enlarged LA
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel - coughing
• Skeletal, Cranial abdomen
– No abnormalities noted
• Airways, Lung fields
– Mild perihilar edema
• Great vessels
– enlarged caudal vena cava
• Smaller vessels
– enlarged pulmonary lobar veins
• Cardiac silhouette
– Generalized cardiomegaly, enlarged LA
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male cocker
spaniel – coughing
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male
cocker spaniel - coughing
• Left Congestive Heart Failure
–
–
–
–
Mild perihilar edema
enlarged pulmonary lobar veins
enlarged LA (generalized cardiomegaly)
Enlarged LV (elevated trachea)
• Right Congestive Heart Failure
– enlarged caudal vena cava
– Generalized cardiomegaly (RV enlargement)
– (ascites, pleural effusion)
Thoracic Rads - Abnormal
Case #1 – 8 year old neutered male
cocker spaniel - coughing
• Diagnosis by echo - DCM
Thoracic Rads - Abnormal
Are rads or echo better for detecting
congestive heart failure?
• radiographs
Are rads or echo better for detecting
enlarged heart chambers?
• echo
Thoracic Rads - Abnormal
Generalized cardiomegaly
(all 4 heart chambers enlarged)
Dogs
• Dilated Cardiomyopathy
• Mitral regurgitation – advanced
• Tricuspid regurgitation - advanced
Cats
• Dilated cardiomyopathy
• anemia
Thoracic Rads - Abnormal
Thoracic Rads - Abnormal
Pseudocardiomegaly
• No significantly enlarged heart chambers
• Significantly enlarged cardiac silhouette
• Pericardial effusion
–
–
–
–
Hemorrhage – HBT or ruptured LA
Right heart failure – modified transudate
Infectious pericarditis
Idiopathic pericarditis
• Peritoneopericardial Diaphragmatic
Hernia
• Pericardial fat
Thoracic Rads - Abnormal
Case #2 – 15 month Maine coon cat
5.1 + 3.5 = 8.5
– tachypnea, lethargy
Thoracic Rads - Abnormal
Case #2 – 15 month Maine coon cat
– tachypnea, lethargy
• Skeletal & cranial abdomen
• Airways, Lung fields
– No abnormalities noted
• Great vessels
– caudal vena cava somewhat enlarged
• Smaller vessels
– No abnormalities noted
• Cardiac silhouette
– Generalized cardiomegaly, apex shifted right
Thoracic Rads - Abnormal
Case #2 – 15 month Maine coon cat
– tachypnea, lethargy
• Skeletal & cranial abdomen
• Airways, Lung fields
– No abnormalities noted
• Great vessels
– caudal vena cava somewhat enlarged
• Smaller vessels
– No abnormalities noted
• Cardiac silhouette
– Generalized cardiomegaly, apex shifted right
Thoracic Rads - Abnormal
Case #2 – 15 month Maine coon cat
– tachypnea, lethargy
• Heart Failure??
– Probably not
• Diagnosis
– Echo showed dilation of LV and RV
– Flea Anemia (PCV 10%)
Thoracic Rads - Abnormal
Case #3 – 12 year old Mini Poodle
- holosystolic murmur L apex
Thoracic Rads - Abnormal
Case #3 – 12 year old Mini Poodle
- holosystolic murmur L apex
Thoracic Rads - Abnormal
Case #3 – 12 year old Mini Poodle
- holosystolic murmur L apex
• Skeletal, cranial abdomen, airways,
Lung fields, Great vessels, small vessels
– No abnormalities noted
• Cardiac silhouette
– VHS high if you include LA (13)
– VHS high normal (10.5) if you exclude LA
– Huge LA
• No signs of congestive heart failure
Thoracic Rads - Abnormal
Case #3 – 12 year old Mini Poodle
- holosystolic murmur L apex
• Diagnosis
– Mitral regurgitation
• Treatment
– Cough suppressants
• Monitoring
– Chest rads every 6 months
– Sooner if respiratory rate while sleeping >35-40
• (no echocardiogram)
Thoracic Rads - Abnormal
Case #3 – 12 year old Mini Poodle
- holosystolic murmur L apex
You can have a Huge LA and even LV
without CHF
CHF is rarely present without enlarged LA
CHF is rarely present without a murmur
Dogs with MR can cough without CHF
Thoracic Rads - Abnormal
Thoracic Rads - Abnormal
3 Most Common
Causes of L Heart
Enlargement in
the Dog
1. MR
2. PDA
3. SAS
Thoracic Rads - Abnormal
Case #5 – 4 year old DSH
4 + 3.5 = 7.5
- Murmur heard on annual – left sternum
Thoracic Rads - Abnormal
Case #4 – 4 year old DSH
- Murmur heard on annual – left sternum
• Skeletal, cranial abdomen, Lung fields,
airways, Great vessels, small vessels
– No abnormalities noted
• Cardiac silhouette
– VHS normal
– Enlarged LA on VD
• No signs of congestive heart failure
Diagnosis by echo - HCM
Thoracic Rads - Abnormal
Case #4 – 4 year old DSH
- Murmur heard on annual – left sternum
LA is seen more easily on the VD in cats
• LA sits more cranial in the cat
LA is seen more easily on lateral in dogs
VHS usually does not include LA in cats
• Other chambers need to be enlarged to perceive
cardiomegaly on the lateral in cats
• Many cats w/ severe heart disease have normal
VHS
Thoracic Rads - Abnormal
Case #5 – 5 month Golden Retriever
- Episodes of collapse with exercise
Thoracic Rads - Abnormal
Case #5 – 5 month Golden Retriever
- Episodes of collapse with exercise
Thoracic Rads - Abnormal
Case #5 – 5 month Golden Retriever
- Episodes of collapse with exercise
• Skeletal, Cranial abdomen, Airways,
Lung fields, small vessels
– No abnormalities
• Cardiac silhouette
– VHS 9.5
– aortic bulge on & small LA bulge on lateral
• No signs of congestive heart failure
• Echo diagnosis – severe SAS
Thoracic Rads - Abnormal
Loss of Cranial Waste
1. Dilated Aortic Arch
• SAS
• PDA
• Tetralogy of Fallot
2. Enlarged RAuricle
• TR
• Heartworm Disease
3. Heart Base Tumor (RA, Aortic Body)
• HSA, chemodectoma, myxosarcoma
Thoracic Rads - Abnormal
Case #6 – 12 yr old Mixed Terrier
- Chronic cough and cyanosis
Thoracic Rads - Abnormal
Case #6 – 12 yr old Mixed Terrier
- Chronic cough and cyanosis
• Skeletal, Cranial abdomen, Vessels
– No abnormalities
• Airways, Lung fields
– Pronounced airway pattern
• Cardiac silhouette
– VHS 10-10.5, RV enlargement, apex shifted L
• No heart failure
Thoracic Rads - Abnormal
Case #6 – 12 yr old Mixed Terrier
- Chronic cough and cyanosis
• Echo diagnosis
– RV thickening
– Suspect pulmonary hypertension
• Clinical Diagnosis
– Severe chronic pulmonary disease
Thoracic Rads - Abnormal
Case #6 – 12 yr old Mixed Terrier
- Chronic cough and cyanosis
What does it mean when the apex is
shifted right on the VD?
– LV enlargement or generalized cardiomegaly
What does it mean when the apex is
shifted left on the VD?
– RV enlargement
Thoracic Rads - Abnormal
Case #6 – 12 yr old Mixed Terrier
- Chronic cough and cyanosis
RV enlargement must be moderate to
severe to see on rads
RA enlargement difficult to appreciate on
rads unless severe (cause)
– TR
Lifting of the apex off the sternum on
lateral view means RV enlargement
Thoracic Rads - Abnormal
3.0 / 1.1 = 2.73
Measuring RV enlargement on
Lateral View of the Thorax
Thoracic Rads - Abnormal
Measuring RV enlargement on
Lateral View of the Thorax
1. Measure heart long axis
• Carina to apex
2. Measure heart short axis
• Widest point perpendicular to long axis
3. Short Axis - Divide Cranial part by
Caudal part
• Cranial is <2.5x Caudal in normal dogs
• (Cr >2.5x Cd) means RV enlargement
Thoracic Rads - Abnormal
Case #7 – 10 month old Chihuahua
Ejection murmur loudest at heart base on
left side
Thoracic Rads - Abnormal
Case #7 – 10 month old Chihuahua
Ejection murmur loudest at heart base on
left side
Thoracic Rads - Abnormal
Case #7 – 10 month old Chihuahua
Ejection murmur loudest at heart base on
left side
• Skeletal, Cranial Abdomen, Airways,
Lung fields, small vessels
– normal
• Great vessels - pulmonary artery enlarged
• Cardiac silhouette – apex shifted R, RV &
RAu enlargement, VHS 8.25
• No signs of Congestive Heart Failure
Thoracic Rads - Abnormal
Case #7 – 10 month old Chihuahua
Ejection murmur loudest at heart base on left
• Causes of enlarged MPA (dogs)
– PS (RPA, LPA, lobar aa/vv not enlarged)
– PDA (lungs overcirculated – lobar aa and vv enlarged, but
not tortuous)
– Pulmonary hypertension (RPA, LPA lobar aa enlarged)
• MPA enlargement
– Not easily seen on lateral in dogs, but sometimes is
– not readily seen in cats
• This case – echo diagnosis
– PS – need spectral Doppler to measure gradient across
– RV thickening, MPA enlargement
Thoracic Rads - Abnormal
LPA, RPA, lobar aa enlarged and tortuous
•Pulmonary Hypertension DDx
1. HW Disease
2. Primary PH
3. Chronic Respiratory
Disease
Thoracic Rads - Abnormal
Case #8 – 6 month old poodle with mitral
murmur found on physical exam
Thoracic Rads - Abnormal
Case #8 – 6 month old poodle with mitral
murmur found on physical exam
Thoracic Rads - Abnormal
Case #8 – 6 month old poodle with mitral
murmur found on physical exam
Continuous murmur in the left armpit
Echo Dx – PDA (with no CHF)
Measuring pulmonary lobar arteries
1.Caudal lobar aa should be same width as a rib
–
Seen best on the VD/DV view
2.cranial lobar aa 0.75x 3rd or 4th rib
–
Seen best on the lateral view
Thoracic Rads - Abnormal
Case #8 – 6 month old poodle with
murmur found on physical exam
Dx – PDA with no CHF
Measuring pulmonary lobar arteries
1.Caudal lobar aa should be same width as a rib
–
Seen best on the VD/DV view
2.cranial lobar aa 0.75x 3rd or 4th rib
–
Seen best on the lateral view
Thoracic Rads - Abnormal
Case #9 – 5 yr old DSH cat
Tachypnea
Thoracic Rads - Abnormal
Case #9 – 5 yr old DSH cat
tachypnea
• Ascites in the cranial abdomen
• Perihilar edema
• HUGE Caudal Vena Cava
• Enlarged pulmonary lobar veins
• Elevated trachea (LV enlargement)
• Enlarged Lauricle on VD
• Marked generalized cardiomegaly (VHS
10.5)
Thoracic Rads - Abnormal
Case #9 – 5 yr old DSH cat
Tachypnea
Enlarged Caudal vena cava
-size varies with respiratory cycle
-only severe enlargement is reliably detected
-maximum width < length T5 or T6
Causes
• Right heart failure, Pericardial effusion
• Mass obstructing Caudal Vena Cava
– Thrombus, tumor
Thoracic Rads - Abnormal
Case #9 – 5 yr old DSH cat
Tachypnea
Thoracic Rads - Abnormal
Case #10 – 2 yr old DSH cat
Tachypnea
Thoracic Rads - Abnormal
Case #10 – 2 yr old DSH cat
Tachypnea
• VHS 7.5 - normal
• Left Heart Failure
– Patchy pulmonary edema (caudal)
– Pulmonary edema can take any pattern in
the cat (perihilar, patchy, cotton-like,
interstitial, alveolar, etc)
• Echo diagnosis – hypertrophic
cardiomyopathy
Thoracic Rads - Abnormal
Case #11 – 6 yr old Westie
ADR
Thoracic Rads - Abnormal
Case #11 – 6 yr old Westie
ADR
Thoracic Rads - Abnormal
Case #11 – 6 yr old Westie
ADR
VHS 7.75 (below normal)
• Clinical diagnosis – hypovolemia
• Causes of microcardia
– Severe dehydration
– Addison’s Disease
– Pneumothorax (heart lifted off the sternum)
• Should also see collapsed lung lobes
Thoracic Rads - Review
Left Heart Failure
• Pulmonary edema (interstitial – mild: alveolar
- severe)
• Pleural effusion in cats
• Pulmonary lobar veins much larger than
arteries
• Enlarged LA + compression of L bronchus
– Not a sign of heart failure per se
– But LHF is rarely present without LA enlargement
• + Enlarged LV
– Tracheal elevation, axis shift right on VD
– Cardiomegaly (increased VHS)
Thoracic Rads - Review
Right Heart Failure
• Pleural effusion
– Can obscure evaluation of the heart, lungs and
great vessels
• Enlarged caudal vena cava
• Ascites
– Modified transudate
• Often concurrent with left heart failure
– Generalized cardiomegaly (increased VHS)
• RHF alone DDx:
– HWDz, Chaga's Disease, pericardial disease, TR
Thoracic Rads - Review
Chronic Bronchitis
• Crackles in small airways
• Increased or mineralized airway pattern
• Peribronchiolar infiltrates
– May progress to bronchopneumonia
– Airway pattern first
– Interstitial pattern as things progress
– Alveolar pattern (air bronchograms) if severe
• Signs of pulmonary hypertension
– Enlarged pulmonary artery and lobar aa
• Cough, cyanosis with no signs of heart failure
Thoracic Rads - Review
Patent Ductus Arteriosus
-left to right shunt (aorta to MPA)
-volume expansion
• + Enlarged pulmonary artery
• + Pulmonary overcirculation
– Enlarged pulmonary lobar aa & vv
• Enlarged descending aorta
• Enlarged LV
– Tracheal elevation
– Increased VHS
• Enlarged LA
– + compression left bronchus
• + pulmonary edema
Thoracic Rads - Review
Sub-Aortic Stenosis
-pressure overload left side
• + Enlarged LV on rads
– Increased VHS
– Not as marked as volume overload
• Enlarged ascending aorta
• Left Heart Failure due to aortic
insufficiency is rare
• Death more often due to arrhythmia
Thoracic Rads - Review
Pulmonic Stenosis
-pressure overload right side
• + Enlarged RV on rads
– Not as marked as volume overload
• Enlarged MPA
• Right Heart Failure due to pulmonic
insufficiency is rare
• Death more often due to arrhythmia
Thoracic Rads - Review
Ventricular Septal Defect
-left to right shunt (LV to RV)
-volume expansion
• + RV enlargement
• + Pulmonary overcirculation
– Enlarged pulmonary lobar aa & vv
• Enlarged LV
– Tracheal elevation
– Increased VHS
• Enlarged LA
– + compression left bronchus
• + pulmonary edema
Thoracic Rads - Review
Ventricular Septal Defect
-left to right shunt (LV to RV)
-volume expansion
• + RV enlargement
• + Pulmonary overcirculation
– Enlarged pulmonary lobar aa & vv
• Enlarged LV
– Tracheal elevation
– Increased VHS
• Enlarged LA
– + compression left bronchus
• + pulmonary edema
Thoracic Rads - Review
Atrial Septal Defect
-left to right shunt (LA to RA)
-lower pressure differential, so no
significant volume expansion
• + RV enlargement
• + RA enlargement
– Enlarged pulmonary lobar aa & vv
• Heart failure is rare
(Radiograph Diagnostic Chart)
Acknowledgements
AAHA Cardiology Handbook
Kittleson M
• Small Animal cardiovascular Medicine, Veterinary
Information Network. Chapter 4 – radiography of
the Cardiovascular System