Examination of the Cardio-Respiratory System in dogs and cats Flashcards
Certain conditions are more likely in certain breeds:
a. Myxomatous degenerative valvular disease (= Mitral valve disease)
b. Tracheal collapse
c. Dilated cardiomyopathy
a. CKCS or small breeds
b. Yorkshire terriers
c. Dobermanns and giant breeds
What information needs to be gathered when assessing cardio-respiratory history?
- Coughing: when? dry or productive?
- Laboured breathing (dyspnoea)
- Tachypnoea
- Exercise
- Collapse
What is orthopnoea?
Standing/sitting to breathe, air-hunger stance
If an animal is dyspnoeic how can this be further refined?
- Inspiratory / Expiratory or Both
- Obstructive versus Restrictive
- Upper vs Lower airway
- If airway noise (stridor, stertor etc. will be upper airway problem)
How can dyspnoea localised if it is upper vs lower?
Upper (inspiration) vs Lower (expiration e.g. bronchial collapse) airway
What can be assessed in the hands-on portion of a cardio-respiratory exam?
- CO signs
- Peripheral perfusion
- Pulse quality
- CRT
- MM colour
- Warmth of extremities
What are the main signs of forwards HF?
- Lethargy, exercise intolerance
- Weak femoral pulses, unable to detect distal pulses (metatarsal)
- Pale MM, slow CRT
- Cold extremities
- Possibly hypothermia
- “Cardiogenic shock”
- Heart sounds “quiet” or “distant” on auscultation
How is cardiogenic shock different to normal shock? How is it treated?
Due to cardiac disease – need to treat differently to normal shock as the heart is failing to pump properly, so giving fluids is not the treatment needed – positive inotropic drug needed
What are the signs of left sided congestive (backwards) HF?
Pulmonary oedema:
- Tachypnoea, both inspiratory and expiratory, restrictive breathing pattern
- Cough in dogs due to left atrial enlargement
- +/- soft inspiratory crackles on auscultation – might not always be audible
What are the signs of right sided congestive (backwards) HF?
- Ascites (positive fluid wave on ballotment)
- Distended jugular veins – pulsating more than normal
- Positive hepatojugular reflux
- Loss of condition
- +/- pleural effusion
What are the normal HRs of dogs and cats?
Dog = 80-140 Cat = 120-200
How can heart murmurs be characterised?
- Location: Left vs Right; Apex vs Base
- Timing: Systolic vs Diastolic vs Continuous
- Grade
What is the most common cause of a continuous murmur?
Patent ductus arteriosus
The left apex of the heart is the point of maximum intensity for which heart valve?
Mitral valve
The left base of the heart is the point of maximum intensity for which heart valve?
Pulmonic and aortic valve
Listening at the left cranio-dorsal portion of the heart in puppies is important for what reason?
To check for a patent ductus arteriosus
What occurs at the heart sounds S1 and S2?
S1: closure of AV valves
S2: closure of semilunar valves
What is the cause of a heart murmur?
Heart murmurs are detected when Turbulent versus Laminar flow is present in the heart / great vessels
Describe innocent murmurs
- 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
- Low pitched
- Get less loud as the puppy grows
Which type of murmurs are never innocnet?
Loud and continuous
Describe a Mitral Regurgitation (Myxomatous degenerative valvular disease) murmur
o Left Apical o Systolic o Loud pan-systolic o Plateau o Grade 4/6
Which part of the stethoscope is used to listen to heart sounds?
Diaphragm for S1 and S2
Bell for S3 and S4
When would S4 be heard in small animals?
Detected in animals which depend on atrial contraction to achieve ventricular filling – e.g. with abnormal LV relaxation, in feline hypertrophic cardiomyopathy
When would S3 be heard in small animals?
When early diastolic filling is abruptly decelerated in a stiff, poorly compliant LV, and filling pressures are high (e.g. DCM)
