Anti-arrhythmic drugs

Question 1

Class I

Answer 1

Membrane stabilising drugs
Sodium channel blockers
Prevent sodium getting through cell membranes.
Slows electrical impulses in heart muscle.

Question 2

Class I - drug examples

Answer 2

Disopyramide
Lidocaine
Flecainide

Question 3

Flecainide

Answer 3

Contraindicated in asthma/severe COPD
Avoid in structural/ischaemic heart disease

Question 4

Class II (beta blocker)

Answer 4

Propranolol
Atenolol
Bisoprolol

Question 5

Class III

Answer 5

Potassium channel blockers
Block potassium channels in cardiac tissue
Prolong repolarisation of cardiac cells which affects duration of the AP

Question 6

Class III - drug examples

Answer 6

Amiodarone
Sotalol (also class II)
Dronedarone

Question 7

Amiodarone

Answer 7

4 weeks before and 12 months after electrical cardioversion to increase success.

Question 8

Dronedarone

Answer 8

Hepatotoxicity and heart failure side effects.

Question 9

Class IV

Answer 9

Calcium channel blockers
Block calcium channels located in muscle cells of the heart and arterial blood vessels.
Rate limiting

Question 10

Class IV - drug examples

Answer 10

Verapamil
Diltiazem (unlicensed)

Question 11

Other anti-arrhythmic drugs

Answer 11

Adenosine
Digoxin