Antiarrythmic Drugs

Question 0

Digoxin function in arrhythmia

Answer 0

(Last line) Rate control ONLY on resting HR
(negative ionotropic)

Only for supraventricular arrhythmia

Enhance vagal tone –> decrease ventricular rate

Question 1

Digoxin

Brand

Answer 1

Digox

Lanoxin

Question 2

Therapeutic range for Afib (Digoxin)

Answer 2

0.8-2 ng/mL

Question 3

Signs of Digoxin toxicity

Answer 3

Nausea/vomiting, loss of appetite and bradycardia

Double vision, confusion, arrhythmias

Question 4

What factors (include electrolytes) increase risk of toxicity (digoxin)

Answer 4

Hypokalemia (<3.5 mEq/L), hypomagnesia, hypercalcemia. Hypothyroidism

Reduce renal function, dehydration

Question 5

Digoxin renal adjustments?

Oral:IV conversion?

When do you obtain digoxin level?

What is the antidote and when do you give it?

Answer 5

Digoxin

CrCl < 50 reduce dose or reduce frequency

Reduce dose by 20-25% when going from po to IV

Get levels 12 to 24 hours after a dose?

Antidote: DigiFab give when levels are high AND symptoms present.

Question 6

Drugs that increase digoxin levels?

Answer 6

Amiodarone, dronedarone, quinidine, propafenone, verapamil

Azoles, macrolide

Question 7

Digoxin and amiodarone or dronedarone what do you do?

Answer 7

Reduce Digoxin by 50%

Question 8

Digoxin is a substrate of what major enzyme

Answer 8

3A4 and P-BP

Question 9

Adenosine (use)

Answer 9

Restore normal sinus rhythm

Slow conduction through AV nodes (supraventricular re-entrant tachyarrhythmias)

Question 10

Class IV (MOA)

Answer 10

Verapamil, Diltiazem.

Block calcium channels (phase 2)

Slow ventricular rate (negative chronotropic )

Question 11

Non-dihydropyridine CCB contraindication

Answer 11

Severe hypotension ( < 90 mmHg)
Acute MI —> heart failure
2nd/3rd degree heart block

May be used in HF with preserved EF

Question 12

Non-dihydropyridine CCB side effect

Answer 12

Edema, constipation ( verapamil), gingival hyperplasia, bradycardia (- chronotropic), arrhythmia (- ionotropic), hypotension

Question 13

Dofetilide (REMS)

BBW

Answer 13

Must be started inpatient with ECG monitoring for at least 3 days

Question 14

Tikosyn monitoring

Answer 14

ECG, BP, SCr, HR, electrolyte (K, Mg)

Question 15

Dofetilide

CrCl < 60mL/min reduce dose

Contraindicated: CrCl <50, azoles, antiviral, verapamil

Answer 15

…

Question 16

Sotalol

Answer 16

Renal adjusted (< 60 mL/ min)

Can’t substitute Betapace with Betapace AFib

Question 17

Dronedarone BBW

Answer 17

HF (class IV or any class recently hospitalized)
Permanent AFib

Question 18

Dronedarone

Side effect

Pregnancy category

Answer 18

QT prolongation, increase SCr

Category X

Question 19

Amiodarone BBW

Answer 19

Must be started in hospital

Pulmonary toxicity

Liver toxicity

Proarrhythmic

Question 20

Amiodarone allergy caution

Answer 20

Contraindicated with iodine allergy

Question 21

Amiodarone side effect

Answer 21

Hypotension, bradycardia, corneal microdeposits, GI, hypothyroidism/hyperthyroidism (more hypo), blue-gray skin

Question 22

Infusion of amiodarone

Answer 22

Non-polyvinyl chloride (PVC) container such as glass, or polyolefin if infusion is longer than 2 hours

Question 23

Amiodarone

Half-life

Pregnancy

Answer 23

40- 60 days

Category D

Question 24

Which patients is amiodarone drug of choice?

Answer 24

Heart failure

Question 25

Dronedarone drug interaction

Answer 25

It's a inhibitor of 2D6 and 3A4

Question 26

Amiodarone drug interaction

Answer 26

Amiodarone is an inhibitor of 2C9, 2D6, 3A4 Reduce warfarin by 30-50% Do not exceed 20 mg Zocor, 40mg of mevacor

Question 27

Class III antiarrhythmic drug interaction

Answer 27

All are proarrhythmic agents (prolong QT) Do not use grapefruit juice Avoid ephedra and St. John wort

Question 28

Class II (beta blocker) MOA

Answer 28

Slow ventricular rate (blocks calcium indirectly) phase 3

Question 29

Class Ib ( allergy contraindication)

Answer 29

Corn

Question 30

Quinidine side effect

Answer 30

Diarrhea, stomach cramp, cinchonism (hearing loss) | Hemolysis, drug induce lupus

Question 31

Procainamide side effect

Answer 31

Metabolized acetylation--> NAPA (metabolite) Lupus, hypotension

Question 32

Disopyramide side effect

Answer 32

Anticholingeric (dry eyes, dry mouth, constipation, urinary incontinence)

Question 33

Class Ic negative iontropic property contraindicated in?

Answer 33

Heart failure and recent MI

Question 34

Class Ib side effect

Answer 34

CNS cross BBB

Question 35

Quinidine drug interaction

Answer 35

Inhibit 2D6 and 3A4 Reduce digoxin by 50%

Question 36

Which rhythm can class IB used for?

Answer 36

Only ventricular arrhythmias