Exam 3- Antiarrhythmics Flashcards
1
Q
Quinidine
A
Class 1a
2
Q
Lidocaine (xylocaine)
A
Class 1b
3
Q
Propafenone (rythmol)
A
Class 1c
4
Q
Beta-adrenergic antagonists
A
Class 2
5
Q
Dronedarone (multaq)
A
Class 3
6
Q
Verapamil (calan, isoptin)
A
Class 4
7
Q
Procainamide
A
Class 1a
8
Q
Mexiletine (mexitil)
A
Class 1b
9
Q
Flecainide (tambocor)
A
Class 1c
10
Q
Amiodarone (cardarone)
A
Class 3
11
Q
Diltiazem (cardizem)
A
Class 4
12
Q
Disopyramide (norpace)
A
Class 1a
13
Q
Sotalol (betapace)
A
Class 3
14
Q
Ibutilide (corvert)
A
Class 3
15
Q
Dofetilide (tikosyn)
A
Class 3
16
Q
Adenosine (adenocard)
A
Misc.
17
Q
What does class 1 mostly block?
A
Phase 0 (Na)
18
Q
What does 1a block?
A
Na and K
19
Q
Dissociation rate for 1a?
A
Intermediate
20
Q
Overall results of 1a?
A
Increase QRS and QT
21
Q
What does 1b block?
A
Na
22
Q
Dissociation rate for 1b?
A
Rapid (<1sec)
23
Q
Overall result of 1b?
A
Decrease QT
24
Q
What does 1c block?
A
Na
25
Dissociation rate for 1c?
Slow (>10sec)
26
Overall result of 1c?
Increase QRS
27
Indication for class 1b?
Ventricular tachycardia and ventricular fibrillation
28
Should you use 1b for atrial arrhythmias?
NO because not useful for anything above ventricles
29
Overall result from 1c?
Slow phase 0 (depolarization)
30
Dissociation rate for 1c?
Slow
31
2 Indications for class 1c?
Atrial fibrillation in patients without CAD or HF
| SVTs
32
MOA of class 2?
Reduce intracellular cAMP:
- reduction of the funny current
- slows and limits Ca++ influx
33
Overall what does class 2 do?
Increase PR interval
Decrease slope of phase 4 depolarization
Prolong depolarization at AV node
34
What do beta blockers end in?
“olol”
35
Indications for class 2?
Treat/prevent Supra-ventricular and ventricular arrhythmias
36
7 adverse effects of beta blockers?
1. Fatigue
2. Bronchospasm
3. Hypotension
4. Impotence
5. Depression
6. Aggravation of HF
7. Masking of symptoms of hypoglycemia in DM
37
MOA of class 3?
Block K+ delayed rectifier current
38
Overall effect of class 3?
Prolong redepolarization period (QT interval)
39
Major side effects to class 3?
Torsade de pointes
| Bradycardia
40
Why is amiodarone considered a big gun?
1. Na channel blocker (class 1)
2. Beta and alpha 1 blocker (class 2)
3. K channel blocker (class 3)
4. L type Ca channel blocker (class 4)
41
When does amiodarone work best?
High heart rate
42
3 unusual pharmacokinetics with amiodarone:
1. Delayed onset
2. Loading dose required
3. T1/2 of ~2months
43
Where is amiodarone metabolized?
Liver
44
What 3 other drugs have interactions with amiodarone?
Digoxin
Warfarin
Statins
45
4 contraindications for amiodarone:
1. Known hypersensitivity (plus iodine)
2. Cardiogenic shock
3. Sinus bradycardia
4. 2nd or 3rd degree AV block
46
What is the only thing that amiodarone does not affect?
Kidneys
47
MOA of class 3:
Non-dihydropyridine Ca++ channel blockers
48
Overall what does class 4 do?
Inhibition of l-type Ca channels that increase PR interval and ERP
- slow rise of AP
- prolonged repolarization at AV node
49
Indications for class 4:
Supraventricular tachyarrhythmias
- atrial flutter/fibrillation
- SVTs
50
4 adverse effects of class 4:
Hypotension
Bradycardia
AV block
Negative inotropy
51
What does digoxin do to central and peripheral vagal tone?
Enhance them
52
MOA of digoxin:
Inhibits Na/K-ATPase pump
- increase Ca
- increase contractility and proarrhythmic potential
53
Indications for digoxin:
Atrial flutter/fibrillation - control of ventricular rate
54
6 toxicity of digoxin:
1. GI upset
2. Altered color perception (halo vision)
3. Malaise
4. Bradycardia
5. AV block
6. Ventricular tachycardia/fibrillation
55
What does adenosine do?
Activates ACh-sensitive K current in atria and sinus and AV bodes
-hyperpolarization and suppression of Ca-dependent APs
56
What is the goal for adenosine?
Produce a complete AV block for a couple of seconds
57
What does adenosine terminate?
PSVTs (reentry involving AVN)
58
MOA of class 1a:
Inhibit Na
Inhibit K
-intermediate
59
MOA of 1b:
Inhibit Na
| -fast
60
MOA of 1c:
Inhibit Na
| -slow
61
MOA of class 2:
Beta adrenergic receptor competitive antagonist
62
MOA of class 3:
Multichannel blocker
| Inhibit K
63
MOA of class 4:
Inhibit Ca L-type
64
Limitations for class 1a:
Risk of torsades de pointes, associated with possible increased mortality
65
Limitations for class 1b:
No efficacy in atrial arrhythmias
66
Limitations for class 1c:
Contraindicated in CAD and HF
67
Limitations for class 2:
Hypotension and bradycardia
68
Limitations for class 3:
Extra-cardiac side effects:
| Risk of torsades de pointes, dependent on renal clearance
69
Limitations for class 4:
Hypotension and bradycardia
