Cardio Review 4

Question 1

Delayed conduction through AV node

Answer 1

1* AV block

Question 2

What ECG characteristics will you see with 1* AV block?

Answer 2

Consistently prolonged PR, normal QRS

Question 3

What is the most common cause of 1* AV block?

Answer 3

High vagal tone

Question 4

What drugs can cause a 1* AV block?

Answer 4

Digoxin, a2 agonists

Question 5

How do you treat 1* AV blocks and mobitz type 1 2* AV blocks?

Answer 5

Tx underlying cause

Question 6

Conduction through AV node is stopped but only transiently

Answer 6

2* AV block

Question 7

What ECG characteristics will you see w/2* AV block?

Answer 7

Some P waves do not have QRS after them, normal QRS

Question 8

What additional ECG characteristics are assoc. w/mobitz type 1 2* AV block?

Answer 8

Prolonged PR prior to block

Question 9

What does high grade mobitx type 2 2* AV block cause?

Answer 9

Bradycardia

Question 10

What is the most common cause of mobitz type 1 2* AV block?

Answer 10

High vagal tone

Question 11

What e-lyte imbalance can cause mobitz type 2 2* AV block?

Answer 11

Hyperkalemia

Question 12

What is the most common cause of mobitz type 2 2* AV block?

Answer 12

Structural AV node disease

Question 13

How do you treat high grade mobitz type 2 2* AV block and 3* AV blocks?

Answer 13

Pacemaker, dopamine, theophylline

Question 14

Conduction through AV node is permanently stopped

Answer 14

3* AV block

Question 15

No impulses are able to travel from the atria to the ventricles

Answer 15

3* AV block

Question 16

What ECG characteristics will you see with a 3* AV block?

Answer 16

P waves w/o QRS, escape beats

Question 17

What e-lyte abnormality can cause 3* AV blocks?

Answer 17

Hyperkalemia

Question 18

How do you ddx a bundle branch block from a ventricular arrhythmia?

Answer 18

BBBs have AV association

Question 19

What ECG characteristics will you see with a BBB?

Answer 19

Wide QRS

Question 20

Delay in conduction/lack of conduction in the bundle branches

Answer 20

Bundle branch block

Question 21

QRS is negative in lead II with which BBB?

Answer 21

R-BBB

Question 22

QRS is positive in lead II in which BBB?

Answer 22

L-BBB

Question 23

What are the most common causes of BBBs?

Answer 23

Idiopathic in some dogs, structural heart disease

Question 24

Absence of atrial depolarization

Answer 24

Atrial standstill

Question 25

What ECG characteristics will you see with atrial standstill?

Answer 25

No P waves/fibrillation/flutter, normal QRS

Question 26

What e-lyte abnormality can cause atrial standstill?

Answer 26

Hyperkalemia

Question 27

How do you treat atrial stnadstill?

Answer 27

Pacemaker, dopamine, theophylline

Question 28

Atrial standstill can be caused by a neuromyopathy in which dog breed?

Answer 28

Springer Spaniel

Question 29

Which dog breed is most predisposed to sick sinus syndrome?

Answer 29

Mini Schnauzer

Question 30

What causes sick sinus syndrome?

Answer 30

Idiopathic: normal SA node cells replaced by fibrous tissue

Question 31

This e-lyte imbalance prolongs repolarization (VPCs/APCs) and lowers resting membrane potential

Answer 31

Hypokalemia

Question 32

This e-lyte imbalance can cause absent P-waves, long PR, V-fib, and PEA if severe

Answer 32

Hyperkalemia

Question 33

This mineral is essential for enzymatic reactions and is involved in postassium regulation

Answer 33

Magnesium

Question 34

Which mineral affects skeletal muscle more than cardiac muslce?

Answer 34

Calcium

Question 35

Which e-lyte imbalance causes decreased action potential threshold (sizures) and long QT?

Answer 35

Hypocalcemia

Question 36

Which e-lyte imbalance causes increased AP threshold, bradycardia, short QT, and VPCs?

Answer 36

Hypercalcemia