Antiarrhythmics

Question 1

Classes for rhythm control

Answer 1

I (A,C) and III

Question 2

Classes for rate control

Answer 2

II and IV

Question 3

What type of drugs are Class I antiarrhythmics?

Answer 3

Na channel blockers
IA: disopyramide, quinidine, procainamide
IB: lidocaine, mexiletine
IC: flecainide

Question 4

What type of drugs are Class II antiarrhythmics?

Answer 4

B blockers

metoprolol

Question 5

What type of drugs are Class III antiarrhythmics?

Answer 5

K channel blockers
Amiodorone, dronedarone
Sotalol, ibutalide

Question 6

What type of drugs are Class IV antiarrhythmics?

Answer 6

Calcium channel blockers

verapamil, diltiazem

Question 7

Strength of Na block in Class I antiarrhythmics

Answer 7

C > A > B

Question 8

Effect of class I antiarrhythmics on repolarization?

Answer 8

C no change
A prolonged
B shortened

Question 9

Class IB antiarrhythmics

Answer 9

Lidocaine (IV), mexiletine (PO)
Rhythm control 
VT only
Best for post MI
most selective for sick cells

Question 10

Class IA antiarrhythmics

Answer 10

Disopyramide, quinidine, procainamide
Rhythm control
VT»»SVT
Also anticholinergic, acquired long QT, hospitalize when starting (tx w/ B or Ca blocker first to prevent reflex increase)

Question 11

Class IC antiarrhythmics

Answer 11

Flecainide
Rhythm control, VT&raquo_space;> SVT
Contraindicated post MI (STRONG)

Question 12

Amiodorone/dronedarone

Answer 12

Class III K blockers
Low dose - 1st line AFib rhythm control
High dose - 1st line VT in abnormal heart, post MI

Question 13

Amiodorone AE (BITCH)

Answer 13

Bradycardia/blue man
Interstitial lung dz/fibrosis 
Thyroid (hyper/hypo)
Corneal/cutaneous 
Hepatic/hypotension

Question 14

Sotalol

Answer 14

Class III K blocker

Good in ICD patients, reduced death/first shock

Question 15

Ibutalide

Answer 15

Class III K blocker

IV

Question 16

Adenosine

Answer 16

Dec AV conduction
T 1/2 seconds
Acute termination of SVT