Cardiac Anti Arrhythmics Flashcards
Group I AA
Sodium channel blockers
Group II
Beta blockers
Group 3
Potassium channel blockers
Group 4
Calcium channel blockers
Group 5 AA
Miscellaneous groups
Group I AA Drugs act on
Phase 0
Group 1A AA MOA
Prolong the AP duration by blocking INa and slowing conduction velocity in atria, purkinje and ventricular cells
Group 1A AA (4)
Procainamide
Quinidine
Disopyramide
Amiodarone
Prolongs AP duration
Intermediate dissociation
Group1A
Blocks Na ch leading to slow upstroke AP
Non specific blockade of K ch (Phase4)
Procainamide
Procainamide SE (4)
SLE-like symptoms
Arthralgia
Arthritis
Torsade
Blocks Na ch but more toxic
Quinidine
Quinidine SE (5)
Cinchonism Tinnitus Cardiac depression GI upset Torsade
Na ch blocker with more antimuscarinic effect
Disopyramide
Disopyramide SE (2)
Heart failure
Atropine-like (mad as hatter etc)
Class1A drugs can (2)
Inc serum digoxin levels
Hyperkalemia
Class1A toxicity tx
Na lactate
Vasopressor
Used for all types of arrhythmias
Procainamide
Class1B drugs (3)
Lidocaine
Mexiletine
Phenytoin
Shortens AP duration
Rapid dissociation
Group1B
selectively affects ischemic or depolarized Purkinje and ventricular tissue and have little effect on atrial tissue
Group1B
Blocks inactivated and activated Na ch especially Purkinje and ventricular cells
In depolarized cells, inc inactivation and slower unbinding leading to depression of conduction
Lidocaine
Shortest AP fast dissociation Group1B
Lidocaine
Used for acute ischemic ventricular arrhythmias after MI, digitalis induced arrhythmias
Lidocaine
Lidocaine SE (2)
Neurologic - covulsion
Hyootension
Group1B least cardiotox
Lidocaine
For chronic arrhythmias, neuropathic pain ventricular arrhythmias
Mixelitine
Digitalis induced arrhythmias, seizure
Phenytoin
Group1B toxicity (5)
Convulsion Cardiovascular depression Allergy Arrhythmia Hyperkalemia
Group1B ECG change
No significant change
Group1C drugs (3)
Flecainide
Propafenone
Movicizine
Minimal effect on AP
Slowly dissociating
Group1C
Powerful depressants of sodium current
Markedly slow conduction velocity in atrial and ventricular cells
Group1 C