Table 7.1 Summary: The clinical approach to horses with arrhythmias

Identify the arrhythmia by:

  1. Careful auscultation to identify the regularity of heart sounds and heart sound intensity. Identify the A sound if possible
  2. Simultaneous palpation of arterial pulse and auscultation of heart sounds
  3. Resting ECG
  4. Exercising ECG such as radiotelemetry
  5. Identifying how often the arrhythmia is occurring (persistent or intermittent)
  6. Establishing whether the arrhythmia is induced or abolished by changes in heart rate, vagal manoeuvres, excitement or exercise

Evaluate the clinical status of the patient:

  1. Can the signs be attributed to the arrhythmia?
  2. Is the animal. sufficiently compromised that it requires urgent treatment?
  3. Is there any evidence of underlying cardiac or systemic disease (clinical examination, echocardiography, clinical pathology, known side-effects of drugs)?

Treatment of the arrhythmia

  1. What, if any, treatment is required?
  2. What are the possible side-effects of the drug, what is its cost?
  3. How does the pharmacology of the drug dictate its use?