Electrocardiogram in Horses

Question 1

How is the horse positioned for an ECG?

Answer 1

standing

Question 2

Explain what the ECG leads look like?

Answer 2

cables are 4-5 feet long with alligator clips
lead system is like the ones used in small animals

Question 3

Where are the leads placed for standard bipolar leads?

Answer 3

white and green on caudal aspect of forelimb
red and black on cranial/lateral stifle

Question 4

When is base-apex lead used and why?

Answer 4

used during anesthesia because it is less affected by movement

Question 5

Where are base-apex leads placed?

Answer 5

white is attached to skin over right jugular groove
black is attached to skin of chest wall at level of left olecranon
green is attached to skin at any location away from the heart

Question 6

What is unique about the P wave in horses?

Answer 6

double peaked (bifid)

Question 7

What is a wandering pacemaker?

Answer 7

regular rhythm with varying shapes of P wave
common and normal in horses

Question 8

What is a second degree AV block?

Answer 8

dropping random P wave, P-Q interval stays the same
common and normal in horses