Chapter 52: Antiarrhythmics Flashcards Preview

NAPLEX > Chapter 52: Antiarrhythmics > Flashcards

Flashcards in Chapter 52: Antiarrhythmics Deck (14)
Loading flashcards...
1
Q

Name all the antiarrhythmics in the Vaughn Williams classification system? (Remember the pneumonic???)

A

Police Department questions
Class IA: procainamide, disopyramide, quinidine

Liquored man
Class IB: lidocaine, mexiletine

From peeing
Class IC: flecainide, propafenone

Class II: Beta-blockers

After drinking scotch in dark
Class III: amiodarone, dronedarone, sotalol, ibutilide, dofetilide

Dirty vehicle
Class IV: diltiazem, verapamil

2
Q

Which (2) class IA antiarrhythmics have strong anticholinergic effects?

A

Disopyramide and quinidine

3
Q

Which class I antiarrhythmic has an active metabolite and should be renally dose adjusted with CrCl

A

Procainamide has an active metabolite N-acetyl-procainamide (NAPA) that is renally cleared.

4
Q

What are the two most common SE of quinidine?

A
  1. Diarrhea (35%)

2. Stomach cramping (22%)

5
Q

Which of the following antiarrhythmics can cause cinchonism (tinnitus, hearing loss, blurred vision, HA, delirium)?

A. Amiodarone
B. Dofetilide
C. Quinidine
D. Procainamide
E. Mexiletine
A

C. Quinidine

6
Q

Procainamide has (2) boxed warnings. What are they?

A
  1. Fatal blood dyscrasias (e.g. agranulocytosis

2. + ANA titer in 50% of patients which may result in drug-induced lupus erythematosus (DILE) in 20-30% of patients

7
Q

A patient will be started on quinidine to manage his arrhythmia. His current medication list is as follows:

Metformin 500mg BID
Lisinopril 20mg daily  
Sertraline 50mg daily
Metoprolol XL 50mg daily
Digoxin 0.125mg daily

What, if any, adjustments should be made to this patients medication regimen?

A

There is a DDI between quinidine and digoxin. Quinidine is a Pgp inhibitor and digoxin is a Pgp substrate. When adding quinidine to a patient already taking digoxin, the digoxin dose should be decreased by 50%. The new digoxin dose should be 0.0625mg daily. Digoxin levels should be continuously monitored until quinidine reaches steady state (5-10 days)

8
Q

What is the brand name for disopyramide?

A

Disopyramide (Norpace®)

9
Q

Which class I antiarrhythmic has a boxed warning for hepatotoxicity?

A

Mexiletine

Quinidine has a warning (not boxed warning) in patients with hepatotoxicity

10
Q

Which antiarrhythmic cannot be given to a patient with an allergy to corn or corn-related products?

A

Lidocaine (Xylocaine®). This allergy is listed as a contraindication

11
Q

Which class of antiarrhythmics are associated with CNS effects since they cross the blood brain barrier?

A

Class IB (Lidocaine and Mexiletine)

12
Q

Which of the following antiarrhythmic agents is appropriate for treating a patient with new onset Afib and a history of HFrEF? (Select all that apply)

A. Lidocaine
B. Pacerone®
C. Propafenone
D. Taztia XT®
E. Flecainide
A

B and D are correct
Amiodarone (Pacerone®) and diltiazem (Taztia XT®) are both appropriate antiarrhythmics indicated for Afib.

A, C, and E are incorrect
Lidocaine is a class IB antiarrhythmic, which, as a class, are only useful for ventricular arrhythmias with NO EFFICACY for supra ventricular arrhythmias like Afib.  Propefanone (Rhythmol®) and flecainide are class IC antiarrhythmic agents.  These agents are sodium channel blockers that also exhibit negative inotropic (decreased contractility) properties.  Propafenone in particular has significant beta-adrenergic receptor blocking effects.  Therefore these agents (Class IC agents: flecainide and propafenone) are absolutely contraindicated in patients with HF (and CI in patients with significant left ventricular hypertrophy, or recent MI)
13
Q

What is the MOA of amiodarone?

A

Amiodarone blocks potassium channels and is a class III antiarrhythmic agent. Class III agents all significantly prolong the refractory period. Amiodarone and dronedarone also block alpha- and beta-adrenergic receptors, and calcium and sodium channels.

14
Q

What is the brand name of propafenone?

A

Propafenone (Rhythmol®)