Equine Cardiology: Diagnostic approach Flashcards
What’s the correlation between size and heart rate?
Bigger the animal - lower the heart rate
When is cardiac insufficiency most detectable?
During maximal performance
What is the presentation of cardiac disease in horses?
- History of poor performance
- Clinical signs of cardiac failure (rare)
- Systemically illness – secondary heart
disease - Incidental finding e.g.
– Pre-purchase examination
– Vaccination
What needs to be assessed in horses considering primary cardiac disease?
- Effect of the cardiac condition on:
– Athletic performance
– Risk of collapse (human injury)
– Resale value
– Risk of developing congestive heart failure (death)
How do you investigate problems in a horse?
*History/signalment
*Clinical examination / auscultation
*+/- ancillary techniques
= ECG , Echocardiography (ultrasound)
What does history and signalment include?
– Include performance history
– current fitness level
– history of any concurrent disease especially respiratory noise, EIPH etc.
Where should you palpate peripheral arterial pulse?
*Below jaw
*Behind eye
What happens with severe aortic valve regurgitation?
*Bounding, hyperdynamic arterial pulse
(Stronger pulse than usual)
How much of the jugular should the jug pulse fill?
1/3 of the height of the jugular
What needs examined considering the CV system?
- Respiratory Rate
- Peripheral oedema
- Mucous membranes
– Colour
– CRT - Hydration status
- Peripheral perfusion
Whats the difference between a physiological and pathological tachycardia?
– Physiological tachycardia:
* Exercise, temperature, stress
– Pathological tachycardia
* Metabolic, compensation for reduced stroke volume, reduced ABP
What are the different rhythms of the heart?
– Regular
– Regularly irregular
– Irregularly irregular
Where is heart beat of horse strongest?
Where the mitral valve sits
Start there then cover whole cardiac window
How can you listen to the heart on the right?
- Pull leg forward
- Stick stethoscope bell right under triceps just dorsal to point of elbow
Which valves shut during ventricular systole?
AV valve (Mitral + tricuspid)
Where does blood flow during ventricular systole?
Aorta +pulmonary artery
When the ventricles repolarise, which valves shut and where does blood move within the heart?
Pulmonic + Aortic valves
What stops the atria and ventricles contracting simultaneously?
Septomarginal band
What is S1?
Ventricles contract
* S1 : Shutting of AV valves
(Mitral/tricuspid)
“ LUB “
What is S2?
Ventricles relax
* S2 : Shutting of Semilunar valves
(Aortic/Pulmonic)
“ DUP “
What is S4?
S4: ATRIAL CONTRACTION
“ B “ VERY COMMON
Just before S1
What is S3?
S3: END OF RAPID VENTRICULAR FILLING
“ D “ LESS COMMON
Just after S2
Where is S3 loudest?
S3 loudest at mitral valve
Where is S$ loudest?
S4 loudest at pulmonic valve?
What is longer at resting heart rate? (Systole/diastole?
What happens at higher HR?
Diastole
Higher HR =
Systole duration = diastole duration
What arteries can be palpated for pulse in the legs?
*Palmar Artery ‘Digital Pulse’
*Median Artery
*Great Metatarsal Artery
What does increased cardiac troponin indicate?
*Myocardial disease
Why can’t we see atrial repolarisation on an ECG?
Happens same time as Ventricular depolarisation (QRS complex) so is hidden
Where do the red and yellow go on lead I? (Black + green)
*Lellow Left - Left arm
*Red Right - Right arm
Black = right leg
Green = left leg
