Examination of the Cardio- Respiratory System in dogs and cats

Question 1

What diseases are more likely in certain breeds?

Answer 1

• Myxomatous degenerative valvular disease (= Mitral valve disease) in CKCS or small breed dogs
• Tracheal collapse in Yorkshire terriers
• Dilated cardiomyopathy (DCM) in Dobermanns & giant breeds of dogs

Question 2

What general history would you take?

Answer 2

• Vaccination & worming status
• Travel outside the UK
• Indoor vs outdoor
• Environment (urban vs rural)
• Other pets or animals in the environment (foxes, slugs etc.)
• Diet / appetite / thirst / V+ / D+ / PUPD
• Access to toxins
• Any change in weight / condition etc.

Question 3

What history would you take in regard to coughing?

Answer 3

 when does the dog cough mainly?
 Is the cough “dry” or productive
(retch/ swallow)?

Question 4

What history would you take in regard to laboured breathing?

Answer 4

 When first noticed? episodic / continuous / getting worse?
 Orthopnoea (posture to optimise breathing)
 Any change in Bark / Miaow?
 Nasal discharge?

Question 5

What history would you take in regard to exercise?

Answer 5

 How much normally? changes?
 Reluctant to exercise?
 Slowing down?

Question 6

What history would you take in regard to collapsing?

Answer 6

 When?
 Describe. Loss of consciousness?
 Colour of tongue / gums?
 Flaccid / rigid? Any muscle movement?

Question 7

If dyspnoea what should you try defining?

Answer 7

• Inspiratory / Expiratory or Both
• Obstructive versus Restrictive
• Upper vs Lower Airway

Question 8

With hands on observation what should you check?

Answer 8

• Check Cardiac Output signs and whether adequate peripheral perfusion
• Pulse quality
• Colour of mucus membranes
• Capillary refill (CRT) (normal <2 seconds)
• Warmth of extremities

Question 9

Forward heart failure is more likely in dilated cardiomyopathy what are the clinical signs?

Answer 9

Lethargy, exercise intolerance
Weak femoral pulses, unable to detect distal pulses (metatarsel)
Pale MM, slow CRT
Cold extremities
Possibly hypothermia
“Cardiogenic shock”
Weak precordial impulse on palpation
Heart sounds “quiet” or “distant” on auscultation

Question 10

What are the signs of left sided CHF (Backwards HF)?

Answer 10

*Pulmonary oedema
* Tachypnoea, both inspiratory and
expiratory, restrictive breathing pattern
* Cough in dogs due to left atrial enlargement
* +/- soft inspiratory crackles on auscultation

Question 11

What are the signs of right sided CHF (Backwards HF)?

Answer 11

• Ascites (positive fluid wave on
  ballotment)
• Distended jugular veins
• Positive hepatojugular reflux
• +/- pleural effusion
• Rarely sub-cutaneous oedema
  in SA

Question 12

How do you check the hepatojugular reflex?

Answer 12

Gentle pressure on the caudal abdomen causes increased distention / pulsation of the jugular veins: sign of increased right sided filling pressure

Question 13

What is normal HR in dogs + cats?

Answer 13

Dog = 80-140
Cats = 120-200

Question 14

If HR abnormal what should you do?

Answer 14

Check femoral pulse at same time to detect pulse deficits

Question 15

What else should you listen out for with the heart?

Answer 15

*Murmurs
*Gallop Sounds

Question 16

With murmurs what details should you examine?

Answer 16

*Location - Left vs Right; Apex vs Base
*Timing - Systolic / Diastolic / Continuous
*Grade - 1-6

Question 17

What is a grade 1 murmur?

Answer 17

1/6 = very quiet murmur, only detected in optimal conditions

Question 18

What is a grade 2 murmur?

Answer 18

2/6 = less loud than the heart sounds

Question 19

What is a grade 3 murmur?

Answer 19

3/6 = as loud as the heart sounds

Question 20

What is a grade 4 murmur?

Answer 20

4/6 = louder than the heart sounds

Question 21

What is a grade 5 murmur?

Answer 21

5/6 = loud heart murmur with a precordial thrill

Question 22

What is a grade 6 murmur?

Answer 22

6/6 = very loud murmur with a precordial thrill, which can be still detected after lifting the stethoscope off the chest wall

Question 23

Where is the point of maximal intensity of heart murmurs?

Answer 23

*Left Apex - Mitral valve
*Left Base - Pulmonic valve + Aortic valve
*Left Cranio-Dorsal - Patent ductus arteriosus (PDA)
*Right side of chest:
-Tricuspid valve (apex)
-VSD (cranio-sternal)

Question 24

What is an innocent murmur what animals are likely to have them?

Answer 24

• Young puppies (and kittens)
• Usually < grade 3/6
• Diminish with growth
• Disappear by 16 – 20 weeks old
• Due to change in foetal to adult haemoglobin
• Can be difficult to distinguish from congenital heart disease

Question 25

How would you listen out for abnormal S3 + S4 sounds?

Answer 25

• Listen for them with the BELL of the stethoscope; very little pressure on the chest wall, over the left apex.

Question 26

With auscultation of the lung field what should you check + where could you get referred sound from?

Answer 26

*Referred sounds = URT
*Check Larynx + Trachea

Question 27

What do crackles and wheezes imply?

Answer 27

*Crackles = Inspiratory - small airway opening
*Wheezes = Expiratory - narrowed airways

Question 28

What should be done during thoracic percussion?

Answer 28

• Percuss both sides of the chest
• Identify any asymmetry / areas of increased or decreased percussion resonance

Question 29

Why would you check thoracic compressibility?

Answer 29

• More useful in cats than dogs
• Useful to detect cranial mediastinal masses
• Also less compressible with significant pleural effusion

Question 30

What is the ABCD classification?

Answer 30

Classification of severity of heart disease/failure

Question 31

What is in risk group A?

Answer 31

*At risk (all animals)
*no structural abnormality of the heart

Question 32

What is in risk group B?

Answer 32

*Structural abnormality, no clinical signs.
- B1 – no remodelling or only very mild dilatation of LA or LV (or both)
- B2 – remodelling evident (e.g. significant LA & LV dilatation)

Question 33

What is in risk group C?

Answer 33

*Structural abnormality with past (treated) or present signs of heart failure. Acute or chronic.
- Moderate: Home treatment of CHF, possibly after hospitalisation treatment.
- Severe: Need for hospitalisation to treat CHF

Question 34

What is in risk group D?

Answer 34

*Persistent or end-stage heart failure signs, refractory to standard therapy. Can be acute decompensation of chronic CHF.