B&B Antiarrhythmic Drugs

Question 1

What are the two class 1a antiarrhythmics?

Answer 1

1. Quinidine 2. Procainamide “The Queen has Proclaimed that she’s #1a”

Question 2

What are the two class 1b antiarrhythmics?

Answer 2

1. Lidocaine 2. Mexiletine “I’m not going to Lidoyou about my trip to Mexico, which is why I got a b”

Question 3

What are the two class 1c antiarrhythmics?

Answer 3

1. Flecainide 2. Propafenone “1citizen Cain is a Propa gentleman”

Question 4

What general category are class 2 antiarrhythmics?

Answer 4

B-blockers

Question 5

What are the 2 class 4 antiarrhythmics?

Answer 5

Block Calcium channels: 1. Verapamil 2. Diltiazem

Question 6

Class 1 drugs block

Answer 6

Sodium channels

Question 7

Class 2 drugs block

Answer 7

Betas

Question 8

Class 3 drugs block

Answer 8

K+ channels

Question 9

Class 4 drugs block

Answer 9

Ca+2 channels

Question 10

Use of antiarrhythmic drugs

Answer 10

Only in dangerous and recurrent arrhythmias. Vtach and Afib that won’t go away.

Question 11

Which antiarrhythmic drugs act on this action potential?

Answer 11

Class I, III (block Na+ channels)- act on ventricular myocytes

Question 12

Which antiarrhythmic drugs act on this action potential?

Answer 12

Class II, IV antiarrhythmics. Sinus and AV node action potentials (Ca+2 and B-blockers)

Question 13

Procainamide side effects

Answer 13

Drug-induced lupus

ANA

Anti-histone

Question 14

When are the 1b drugs useful?

Answer 14

Ischemia

Question 15

How does Lidocaine terminate arrhythmias?

Answer 15

It abolishes the re-entry circuit

Question 16

What’s a sign of toxicity in Mexiletine?

Answer 16

Tremor

Question 17

CAST trial findings

Answer 17

Tested the suppression of arrhythmias hypothesis. Treated patients with 1c drugs. Less arrhythmias but increased risk of arrhythmic death (the ones they had were more deadly). Resulted in a dramatic reduction in use of antiarrhythmics in general.

Question 18

Can you use 1c drugs in patients with heart structural abnormalities?

Answer 18

NO!

Question 19

T/F: all class 1 drugs have some use-dependence?

Answer 19

True

Question 20

What’s a concern for patients on 1c’s in relation to use dependence

Answer 20

Toxicity at heart rates because more binding at high heart rates

Question 21

What can QT prolongation from Ia and III drugs turn into?

Answer 21

Torsades de Pointes

Results in cardiac arrest

Question 22

Amiodarone 3 facts:

Answer 22

1. Iodine- thyroid
2. Sun sensitivity
3. Safer than others