Chapter 52: Antiarrhythmics Flashcards
Name all the antiarrhythmics in the Vaughn Williams classification system? (Remember the pneumonic???)
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
Which (2) class IA antiarrhythmics have strong anticholinergic effects?
Disopyramide and quinidine
Which class I antiarrhythmic has an active metabolite and should be renally dose adjusted with CrCl
Procainamide has an active metabolite N-acetyl-procainamide (NAPA) that is renally cleared.
What are the two most common SE of quinidine?
- Diarrhea (35%)
2. Stomach cramping (22%)
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
C. Quinidine
Procainamide has (2) boxed warnings. What are they?
- 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
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?
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)
What is the brand name for disopyramide?
Disopyramide (Norpace®)
Which class I antiarrhythmic has a boxed warning for hepatotoxicity?
Mexiletine
Quinidine has a warning (not boxed warning) in patients with hepatotoxicity
Which antiarrhythmic cannot be given to a patient with an allergy to corn or corn-related products?
Lidocaine (Xylocaine®). This allergy is listed as a contraindication
Which class of antiarrhythmics are associated with CNS effects since they cross the blood brain barrier?
Class IB (Lidocaine and Mexiletine)
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
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)
What is the MOA of amiodarone?
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.
What is the brand name of propafenone?
Propafenone (Rhythmol®)
