Anti-Arrythmia Flashcards

1
Q

Which phase does I(kr), I(ks) correspond to?

A

Phase 3

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

Which phase does I(to) correspond to?

A

Phase 1

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

Which phase does I(Na) correspond to?

A

Phase 0

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

Which phase does I(Ca) correspond to?

A

Phase 2

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

Why does the action potential fall from phase 2 > 3

A

Influx of Ca2+ is less than efflux of K+

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

Which channel do class 1 anti-arrhythmic drugs target?

A

Sodium channels

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

What class of anti-arrhythmic is procainamide?

A

Class 1A

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

What is the effect of procainamide?

A
  • Reduces rate of Phase 0 rise
  • Reduces conductivity & automaticity
  • Increases ERP & APD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the effect of lidocaine?

A
  • Reduces rate of Phase 0 rise
  • Shortens phase 3 repolarisation
  • Reduces automaticity
  • Shortens APD

No change to ERP

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

What class of anti-arrhythmic is lidocaine?

A

Class 1B

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

What class of anti-arrhythmic is Flecainide?

A

Class 1C

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

What is the effect of flecainide?

A
  • Reduces rate of Phase 0 rise
  • Shortens Phase 3 repolarisation
  • Reduces conductivity & automaticity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the clinical indication for flecainide?

A

Refractory ventricular tachycardias

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

What are class 2 anti-arrhythmic drugs?

A

Beta-blockers

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

What are the effects of class 2 anti-arrhythmics?

A
  • Reduces Phase 4 depolarisation
  • Reduces HR & conductivity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the effect of amiodarone?

A
  • Prolongs Phase 3 repolarisation
  • Increases ERP & APD

amiodarone is a K-channel blocker

17
Q

What class of anti-arrhythmic do verapamil & diltiazem belong to?

A

Class 4; non-DHP calcium channel blockers

18
Q

What channel do class 3 anti-arrhythmics block?

A

Potassium channels

19
Q

What class of anti-arrhythmics is amiodarone?

A

Class 3; potassium channel blockers

20
Q

What is the effect of verapamil & diltiazem?

A
  • Prolong Phase 4 depolarisation
  • Reduces conductivity on AV node
  • Increases ERP & APD
21
Q

Why are non-DHP calcium channel blockers preferentially used over DHPs?

A

non-DHPs target the calcium channels on AV nodes while DHPs target the channels on smooth muscles

22
Q

Which drug is indicated in emergency supraventricular tachycardia?

A

Adenosine; rapid onset

23
Q

Adenosine suppresses ________ and increases the ______________

A

Adenosine suppresses AV nodal conduction and increases the AV nodal refractory period