Antiarrhythmic Drugs Flashcards
Local anesthetic activity
Phase 0: depolarization
Divided based on AP duration
Depress tissues which are frequently depolarizing or relatively depolarized at rest
1 Na
1A prolong acute MI
1B shorten most selective post MI
1C none refractory arrhythmias
Singh Vaughan Williams Classification
1 Na blockers
2 B
3 K
4 Ca
1A INa and some Ik channels Slowed conduction velocity and pacemaker activity For atrial and ventricular arrhythmia WOF Arrhythmia and hypotension Hyperkalemia exacerbates toxicity
Procainamide
Disopyramide
Quinidine
Post MI
WOF drug induced lupus
Procainamide
WOF marked antimuscarinic effects
Disopyramide
WOF torsades, CINCHONISM, autoimmune ITP
Quinidine
Cinchonism
HA
Vertigo
Tinnitus
WOF Arrhythmia and hypotension
Class 1A overdose
DOC SODIUM LACTATE
1B
No effect on Ik
DOC for vent arrhythmias post MI, digoxin induced arrhythmias
Least cardiotoxic
Lidocaine
Agranulocytosis
Clozapine antipsychotic Cotrimoxazole Colchicine Aminopyrine NSAID Phenylbutazone NSAID PTU Indomethacin Tocainide 1B
1C
INa
DOC for refractory arrhythmias
Contraindicated for post MI arrhythmias
Flecainamide
WPW
Procainamide
Amiodarone
1A
Class 2
Phase 4
Prolonged PR
Inc QRS duration
B blockers
Class 2 and 3 properties
Sotalol
DOC for perioperative and thyrotoxic arrhythmias
SVT
Esmolol
Longest acting B blocker
Nadolol
Low lipid solubility
Atenolol
Class 3 Phase 3 Prolong AP duration Block Ik Increase QT
Dofetilide
Sotalol
Amiodarone
Selective Ik block
Treatment and prophylaxis for a fib
WOF torsades
Dofetilide
Ik and B block
WOF torsades
Sotalol
Strong Ik block
Group 1 slows conduction velocity
Groups 2 and 4 confer antiarrhythmic activity
Refractory arrhythmias
MOST EFFICACIOUS ANTIARRHYTHMIC
WOF microcrystalline deposits in cornea and skin (toxicity)
Amiodarone
Class 4
Inc PR interval
NDHP Ca blockers
Inc diastolic Ik of AV node
DOC for paroxysmal SVT and AV nodal arrhythmias
Adenosine
Depress ectopic pacemakers cussed by digitalis
K
