Anti-Dysrhythmics PHARM

Question 1

Propafenone
Vaughan Williams Classification Anti-Dysrhythmics

Answer 1

Class I
Blocks sodium channels
Phase 0 fast action potential in the heart
his-purkinje system, atrium/ventricle myocardium
prevents conduction

Question 2

Propafenone
Indication

Answer 2

Acute treatment of AF

Pill in pocket cardioversion

Question 3

Propafenone
MOA

Answer 3

Blocks sodium channels
blocks the fast AP in the ventricle/atrium myocardium and His-purkinje system

Decreases conduction atrium and ventricle

Prolonges PR and QT intervals

Question 4

Propafenone
SE/AE

Answer 4

N/V/D/Constipation

Worsen dysrhythmias

Heart failure
More common first dose and/or Hx. MI

Question 5

Propafenone
Patient Educaiton

Answer 5

Report S&S heart failure
- dypsnea, SOB, nocturnal coughing, edema

Report S&S worsening dysrhythmias
- palpitations, fainting, dizziness, weakness, fatigue

Question 6

Amiodarone
Vaughan Williams Classification of Anti-dysrhythmics

Answer 6

Class III
Blocks potassium channels
Blocks phase 4 of the fast action potential
His-purkinje, myocardium atrium/ventricle
Prolonges refractory period
slows automaticity/heart beat

Question 7

Amiodarone
Indication

Answer 7

LAST RESORT MEDICATION

Acute treatment atrial fibrillation
Pharmacological conversion
pill in pocket approach

Question 8

Amiodarone
MOA

Answer 8

1. Blocks potassium channels
   prolonges refractory of the atrium/ventricle myocardium
   slows heart beat

Prolonges PR and QT intervals

2. Blocks sodium channels
   Phase 0 fast AP (atrium/ventricle) blocks conducion
3. Blocks calcium channels (beta receptors)
   Phase 2 fast AP (atrium/ventricle) blocks contraction
   Phase 0 and 4, slow AP (SA and AV node) blocks conduction and automaticity

VERY STRONG DRUG
- decreases conduction
- decreases HR
- decreases contractility

Question 9

Amiodarone
Pharmacokinetics

Answer 9

1/2 life is 25 to 110 days
four 1/2 lives to wash out (up to 1 year)
metabolized by CYP3A4
Lipid soluble
accumulates in body

Question 10

Amiodarone
SE/AE

Answer 10

TOXIC TO:

Heart: fatal dysrhythmias

Lungs: fibrosis, pneumonitis

Eyes: blindness, neuritis, neuropathy

Skin: Burn, blue colour

Thyroid: hypo/hyperthyroidism

Liver: failure

Question 11

Amiodarone
Prescriber Considerations

Answer 11

Do not combine with Class I (sodium blockers), Class II (beta blockers), or Class III (potassium blockers) - exacerbation cardiotoxicity

Do not combine with CYP3A4 inhibitors (non-dihydropyridine CCB)

Monitor
- Thyroid
- ECG
- Liver
- Vision
- X ray, PFT
- electrolytes

Question 12

Sotalol
Vaughan Williams Classification Anti-dysrhythmic drugs

Answer 12

Class III
Blocks potassium channels
prevents phase 4 fast AP (ventricle/atrium, his-purkinje)
delays heart beat

Class II
Non-cardioselective beta blocker
blocks calcium channels
prevents phase 2 of the fast action potential (ventricle/atrium)
decreases contractility
prevents phase 0 of the slow action potential
decreases conduction

ECG findings
- prolonged QT interval
- prolonged PR interval

Question 13

Sotalol
MOA

Answer 13

• Decrease HR, conduction, contractility

Question 14

Sotalol
SE

Answer 14

• bradycardia
• AV heart blocks
• heart failure
• rebound tachycardia
• impaired awareness hypoglycemia
• hypoglycemia
• insomnia, depression, hallucinations
• life threatening QT dysrhtuhmias