Antidysrhythmics Drugs

Question 1

Dysrhythmias/Arrhythmias

Answer 1

Defined as an abnormality in the rhythm of the heartbeat.

Question 2

2 Basic types:

Answer 2

Tachydysrhythmias (increased heart rate)
Largest group of dysrhythmias

Bradydysrhythmias (decreased heart rate)

Question 3

Atrial dysrhythmias prevent

Answer 3

proper filling of the ventricles, decrease cardiac output & can lead to blood pooling & clotting

Question 4

Ventricular dysrhythmias are life-threatening because

Answer 4

inadequate filling & pumping can lead to decreased or absent cardiac output.

Question 5

Symptoms of dysrhythmias:

Answer 5

Palpitations
Angina
Dyspnea
Faintness
Death

Question 6

Supraventricular tachycardia

Answer 6

HR 150-250

Question 7

Cardiac Action potentials


Answer 7

virtually all drugs used to tx dysrhythmias can also cause dysrhythmias.

Question 8

Types of Antidysrhythmic Drugs

Answer 8

class 1 to 5

Question 9

Antidysrhythmic Drugs
 Class I: Sodium Channel Blockers (Phase 0)

Answer 9

Slows Conduction & delays repolarization (blocks k+ channels)

Quinidine
interacts with digoxin

Question 10

class 1B

Answer 10

Slows conduction, reduces automaticity & accelerates repolarization. (Little/no effect on EKG)
Lidocaine (IV)

Question 11

class 1C

Answer 11

Reduce conduction velocity & delay ventricular repolarization.
Flecainide
Propafenone

Question 12

Antidysrhythmic Drugs
Class II: Beta Adrenergic Blockers (Phase 2 & 4)

Answer 12

Nearly identical to Class IV: CCBs

Acebutolol
Propanolol
Esmolol
Sotalol

Question 13

Antidysrhythmic Drugs
Class III: Drugs that Delay Repolarization (Phase 3)

Answer 13

block K channels; used for dysrhythmias; delays repolarization;

Sotalol
Amiodarone

Question 14

Amiodarone

Answer 14

Approved for treatment of life-threatening ventricular dysrhythmias

no grape fruit juice
TOXICITY

Question 15

Antidysrhythmic Drugs
Class IV: Calcium Channel Blockers (Phase 2 & 4)

Answer 15

Drugs that delay repolarization
Nearly identical to Class II: Beta Blockers

diltiazem
verapamil

Question 16

Antidysrhythmic Drugs
Class V: Other (Adenosine and Digoxin)

Answer 16

Decrease conduction through the AV node and reduce automaticity in the SA node.
Has an extremely short half-life: 1.5-10 secs.
IV bolus only-push fast and hard

Question 17

adenosine

Answer 17

Treatment of supraventricular tachycardia

Question 18

Atropine (an anticholinergic drug)

Answer 18

treatment of hemo-dynamically significant bradycardia & some types of heart block.

Question 19

Antidysrhythmic Drugs
Patient Teaching

Answer 19

Avoid alcohol
Avoid caffeine
Avoid tobacco