Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

RUSVM LAM I > Equine cardiovascular system > Flashcards

Equine cardiovascular system Flashcards

1
Q

What is the difference between normal and abnormal jugular pulse?

A

Normal: lower third of neck
Abnormal: higher than lower one third when neck upright

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the four heart sounds in a horse

A

S1 (lub)- closure of AV valves, opening of semilunar valves, initial ejection of blood
S2 (dub)- closure of semilunar valves
S3 (ahh)- end of rapid filling phase
S4 (ba)- atrial contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are normal heart sounds generated by?

A

Turbulence of blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If cardiac sounds are absent or diminished, what could you suspect?

A

thick chest wall (draft horse), pericarditis, pulmonary consolidation, diaphragmatic hernia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the normal equine HR?

A

26-44 BPM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the preferred method of evaluating the equine heart?

A

Echocardiography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are radiographs most helpful for?

A

Evaluation of extent of pulmonary involvement in suspected cardiac case

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the automaticity order of the cardiac nodes?

A

SA node –> AV node –> HIS –> myocardial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are three causes of changes in automaticity?

A

Alterations in autonomic nervous system tone
Alterations in electrolyte status
Presence of drugs/disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is ectopic foci?

A

Cells outside pacemaker centers developing membrane characteristics similar to those of pacemaker cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is torsades de pointes?

A

Atypical rapid ventricular tachycardia with periodic waxing and waning of amplitude of the QRS complexes on the ECG as well as rotation of the complexes about isoelectric line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Conduction through the AV node is profoundly affected by what?

A

Vagal tone- predominates at rest in horse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the most commonly used lead in equine?

A

Bipolar lead- base –> apex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are the leads placed on the horse?

A

Positive lead on left thorax
negative lead on right jugular furrow
ground lead at any point away from heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Electrocardiogram is most commonly used for what?

A

detection of dysrhythmias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

T/F: It can be normal to see 1st degree AV block in a horse

A

TRUE

17
Q

What is the most frequent manifestation of high vagal tone in the normal horse?

A

Second degree AV block

18
Q

What is the difference in Mobitz type I and Mobitz type II?

A

Mobitz Type I (wekenbach)- gradual increase between S4 and S1 before beat dropped
Mobitz Type II- fixed interval between S4 and S1- PATHOLOGIC

19
Q

What arrhythmia has complete AV dissociation and requires electrical pacing for the tx?

A

Third-degree AV block

20
Q

What is the most common PATHOLOGIC arrhythmia of the horse?

A

Atrial fibrillation

21
Q

Why are horses predisposed to developing A-fib in normal atrial tissue?

A

large atrial surface area

22
Q

What are the two forms of A-fib?

A

Paroxysmal: occurs during race and can disappear with deceleration of HR (furosemide pre-race or oral bicarbonate pre-race can cause this)
Sustained

23
Q

What is the treatment used if the HR <60

A

Quinidine therapy

24
Q

What is the treatment used if the HR > 60

A

Digitalize first (digoxin)

25
Q

What is the treatment used if HR > 60 and no underlying disease is found?

A

Digitalize first, then convert to quinidine once HR decreased

26
Q

What is the treatment used if HR > 60 and underlying cardiac disease?

A

treat for heart disease

27
Q

When would you use IV vs. oral quinidine?

A

IV- arrhythmia developed within 72 hours

Oral- arrhythmia persisting longer than 72 hours

28
Q

What is the MOA of quinidine?

A

blocks fast inward Na current in myocardium causing increased myocardial refractory period and decreased conduction velocity

29
Q

What is acute toxicity of quinidine treated with?

A

IV sodium bicarbonate- promotes quinidine binding and decreases amount of active drug

30
Q

What is the maximum dose of quinidine that should NOT be exceeded?

A

12 mg/kg IV

31
Q

How many VPCs are diagnostic of VT?

A

4+

32
Q

What is the initial/most frequent used therapy for VT?

A

Lidocaine

33
Q

What drug is used to treat refractory ventricular tachycardia?

A

Propafenone

34
Q

What drug is used to treat life-threatening ventricular tachycardia or v-fib?

A

Bretylium tosylate

RUSVM LAM I (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions