Antiarrhythmic pharmacotherapy Flashcards
class I antiarrhythmics block what channel?
sodium
class II antiarrhythmics block what channel?
beta
class III antiarrhythmics block what channel?
potassium
class IV antiarrhythmics block what channel?
calcium
class Ia antiarrhythmics have what effect on sodium levels
moderate sodium blockage
class Ib antiarrhythmics have what effect on sodium levels
mild sodium blockage
class Ic antiarrhythmics have what effect on sodium levels
marked sodium blockage
dcreasing conduction velocity, no effect on repol
what must be used first before quinidine in aF?
digoxin
where is quinidine metabolized?
liver
what is the main cardiac adverse effect of quinidine?
prolonged QT interval (torsade de pointes)
what is the main metabolite of procainamide?
NAPA
what are the main adverse effects of procainamide?
QT prolongation
drug induced lupus
where is disopyramide cleared?
kidney
what are the adverse effects of disopyramide?
potent anticholinergic (dryness)
what type of local anesthetic is lidocaine?
amide
what is a benefit of lidocaine?
minimal effect of QT or QRS
lidocaine is only effective for what type of arrhythmia?
ventricular
flecainide is only effective for what type of arrhythmia? what is their first line use?
atrial (SVTs with normal heart function)
atrial fibrillation only
class Ic antiarrhythmics are contraindicated in what population?
anyone with structural heart disease (CHF)
what is the indication for propafenone?
without sig CHF that have aF or sustained VT/VF
torsades, AV block, CHF
MOA of beta blockers
prolongs AP and slows HR
what is the only class of antiarrhythmics found to reduce mortality in arrhythmia patients?
beta blockers
what kind of drug is sotolol
beta blocking agent with class III properties
also blocks potassium channels
what are the indications for sotolol?
AF and sustained VT/VF
what is the main side effect of sotolol?
torsades de pointes
potent QT prolongation
what class of drug is amiodarone? what are its effects on channels?
class III
has effects in all four Vaughn-WIlliams classes (all channels)
what is the principal MOA of amiodarone?
delayed repolarization by prolonging APD and ERP
what are the indications for amiodarone?
all types of arrhythmias, increasingly for VF
why does amiodarone have such potent side effects?
huge volume of distribution
long tissue half life
short peripheral half life
what are the cardiac and pulmonary side effects of amiodarone?
cardiac - torsades
pulmonary - fibrosis
amiodarone is only one of two antiarrhythmics safe to use in what condition?
CHF
what are the thyroid and ocular side effects of amiodarone?
thyroid - hypo or hyperthyroidism
ocular - corneal deposits, halos, photophobia, retinopathy
what are the neuro and derm side effects of amiodarone?
neuro - tremor, ataxia, peripheral neuropathy, seizure
derm - photosensitivity, blue-gray discoloration
what are the hepatic and GI side effects of amiodarone?
hepatic - elevated transaminases
GI - loss of taste
what kind of drug is dronaderone? what is its clinical use?
derivative of amiodarone
AF
dronaderone is contraindicated in what population?
CHF
what are the indications for dofetilide?
acute conversion of AF to NSR and for maintenance of NSR
what is the main adverse effect of dofetilide?
HIGH incidence of torsades de pointes
treatment for AF with no other heart disease?
flecainide or propafenone
treatment for AF with history of CAD, but normal EF?
sotolol
treatment for AF with CHF?
amiodarone, dofetilide
what are the rate control drugs for atrial arrhythmias?
beta blockers
diltiazem
digoxin
