Antiarrhythmia Drugs

Front 1

Class I

Back 1

Na channel blockers
hyperkalemia increases their cardiac toxicity

Front 2

Class Ia

Back 2

Procainamide, Disopyramide, Quinidine
all types of arrhythmias
slows conduction in atria, P fibers, ventricle

Front 3

Class Ib

Back 3

Lidocaine, tocainide
Selectively inhibits P fibers and ventricle

Front 4

Flecainide

Back 4

Class Ic: prolongs QRS
Approved only for v tach that tends to progress to vfib at unpredictable times
(Ic drugs cause greater mortality than placebo)

Front 5

Procainamide

Back 5

common use: arrhythmia during acute phase MI
**causes reversible Lupus (HIPP)

Front 6

Quinidine

Back 6

ass'd w/ torsade de pointes
can cause thrombocytopenic purpura
decreases clearance of digoxin

Front 7

Disopyramide

Back 7

Class IA
-reduces velocity of phase 0 depol (Na channel blockade)
-increases AP duration
-atrial and vent extrasystoles and tachyarrhythmias

Front 8

Lidocaine

Back 8

attenuates phase 4 depol (Ib)
esp for post-MI arrhythmias, digoxin toxicity (Qbank: acute management of vent arrhythmias during ischemia - surgery or MI)
-IV admin

Front 9

Class II

Back 9

Beta-blockers
dec cAMP -> dec Na/Ca currents
esmolol: short-acting, exclusively for acute arrhythmias
Propanolol: prophylactic in px w/ MI b/c has protective effect

Front 10

Class III

Back 10

K channel blockers
increased refractory per and dec ability to respond to tachycardia (hallmark is prolonged AP)

Front 11

Sotalol

Back 11

K blocker, Class III
may -> torsade de pointes

Front 12

Ibutilide

Back 12

for a.flutter and afib
may -> torsade de pointes

Front 13

Amiodarone

Back 13

Class III (increases duration of AP)
broad spectrum
many toxicities, so not used as much
approved for use for refractory arrhythmias (esp ventricular)

Front 14

Class IV

Back 14

Ca channel blockers (verapamil)
AV node

Front 15

Adenosine

Back 15

given as IV bolus -> slows AV node conduction
v. effective against AV node arrhythmias (Drug of Choice)
v. short duration

Front 16

Digitalis

Back 16

for rapid atrial or AV node arrhythmias (has parasympathomimetic action)
-afib, a.flutter
-never give for WPW - makes arrhythmia worse

Front 17

K+

Back 17

depresses ectopic pacemakers, including those caused by digitalis toxicity

Front 18

Mg+

Back 18

sim to K+
may be effective in some cases of torsade de pointes

Front 19

Propanolol

Back 19

-Class II
-dec SA automaticity, slows AV conduction, inc AV node refratoriness
-ventricular/supraventricular arrhythmias and for slowing vent rate during afib/aflutter