CV130 Antiarrhythmic Drugs

Question 1

What are the adverse effects of quinine?

Answer 1

1) cinchonism - CNS toxicity including tinnitus, confusion, hearing loss, visual disturbances
2) QT prolongation

Question 2

What is the effect of Quindine?

Answer 2

1) class 1 A drug

2) has anticholingeric effect that can increase AV nodal conduction

Question 3

What are the effects of procainamide?

Answer 3

1) Class 1A drug

2) Less anticholinergic effect than quinidine

Question 4

What is the drug of choice out of the Class 1A’s?

Answer 4

Procainamide because it can also be given through IV

Question 5

What are the adverse effects of procainamide?

Answer 5

1) myocardial depressant at high doses
2) lupus-like syndrome
3) QT prolongation

Question 6

What is the effect of quinidine?

Answer 6

1) more anticholinergic than quinidine

2) strong myocardial depressant

Question 7

When is disopyramide used?

Answer 7

rarely used. Used when need negative inoptropy

Question 8

What are the adverse effects of disopyramide?

Answer 8

1) anticholinergic effects - constipation, urinary retention, glaucoma worsening
2) QT prolongation & associated arrhythmias

Question 9

When are class 1B drugs used?

Answer 9

• acts on diseased and ischemic tissues, especially in ventricular tissues
• reserved for ventricular tachyarrhythmias

Question 10

How are class 1B adverse effects different from class 1B?

Answer 10

Class 1B does not prolong the QT

Question 11

In what situation is lidocaine used?

Answer 11

for people with weak hearts because it causes little myocardial depression

Question 12

How is lidocaine administered?

Answer 12

IV

Question 13

What makes lidocaine unique?

Answer 13

it is very specific for ventricular tissues, especially in ischemic areas

Question 14

What is the structurally similar congener of lidocaine that comes in pill form?

Answer 14

mexiletine

Question 15

What are the adverse effects of lidocaine?

Answer 15

CNS toxicity - dose-related dizziness, parenthesis, confusion, delirium, coma, seizures

Question 16

In what types of patients should class IC drugs be avoided?

Answer 16

in patients with structural heart disease

Question 17

How does Flecainide work?

Answer 17

• reduces conduction velocity in all tissues without any significant increase in QT.
• can depress ventricular function

Question 18

what are the adverse effects of flecainide?

Answer 18

1) CNS toxicity
2) myocardial depression
3) proarrhythmia

Question 19

What are the adverse effects of propafenone?

Answer 19

1) CNS toxicity
2) myocardial depression
3) proarrhythmia

• same as flecainide

Question 20

Explain beta-blockers and their association with ischemia

Answer 20

They can improve ischema which may also indirectly reduce schema-induced arrhythmias

Question 21

How do beta-blockers help supra ventricular tachycardias?

Answer 21

1) if arrhythmia is self-sustaining in the atria - slows down ventricular rate
2) if the arrhythmia needs the AV node for re-entry - may stop the arrhythmia

Question 22

What are adverse effects of beta blockers

Answer 22

1) may cause hypotension and bradycardia

2) may worsen asthma

Question 23

which drug has the most versatile use, and has effects that fall in all classes?

Answer 23

amiodarone

Question 24

what are the advantages of using dronedarone over amiodarone?

Answer 24

even though it is less efficacious, there is less thyroid, pulmonary and liver toxicity associated with this drug

Question 25

What are the adverse effects of dronedarone?

Answer 25

1) GI intolerance

2) increased mortality

Question 26

when is sotalol used?

Answer 26

for supraventricular and ventricular arrhythmias

Question 27

What are the adverse effects of sotalol?

Answer 27

1) proarrhythmia

2) similar profile to beta blockers

Question 28

How does sotalol work?

Answer 28

since it is a racemic mixture, it blocks K channels but also is a beta blockade

Question 29

What are the predominant effects of verapamil and diltiazem?

Answer 29

slowing of AV node

Question 30

How does adenosine work?

Answer 30

1) works at adenosine receptors which results in activation of K channels. This slows SA node and Av node conduction
2) inhibits adenylate cyclase –> decreased cAMP –> reduction in If and Ca channels

Question 31

What are the adverse effects of adenosine?

Answer 31

transient but severe flushing, chest pain and shortness of breath

Question 32

Which drugs are used to slow AV node conduction?

Answer 32

1) CCBs
2) beta blockers
3) adenosine

Question 33

What drugs are used to suppress atrial arrhythmias?

Answer 33

1) class 1A
2) class 1C
3) beta blockers
4) class III

Question 34

What drugs are used to suppress ventricular arrhythmias?

Answer 34

1) Class 1 (A,B,C)
2) Beta blockers
3) Class III
4) sometimes CCBs