Flashcards in Antiarrhythmic Drugs Deck (12):
Often induced by antiarrhythmics and other drugs that change the shape of the action potential and prolong the QT interval.
Seen in the ECG as polymorphic ventricular tachycardia, often displaying waxing ang waning QRS amplitude.
Torsades de pointes
Class I antiarrhythmics act on phase _____ of cardiac action potential.
For WPW: (2)
I am the Queen who Proclaimed Diso's pyramid
Procainamide, Amiodarone (Group III anthyarrhthmic with class 1A activity.)
Treatment of Class 1A overdose
- ______________ to reverse drug-induced arrhythmias
- ______________ to reverse drug-induced hypotension if indicated
Examples of Class 1B antiarrhythmics: (4)
Lidocaine (DOC for ventricular arrhythmias post-MI, digoxin-induced arrhythmias)
Phenytoin (alternative to lidocaine)
NOTE: 1B is best post-MI, atrial arrhythmias due to digitalis
What are the drugs (not necessarily antiarrhythmics) that can cause agranulocytosis? (8)
Examples of Class 1 antiarrhythmics which have no effect on the action potential but increases the QRS duration and are reserved for refractory arrhythmias: (4)
NOTE: 1C is contraindicated post-MI.
Class 2 antiarrhythmics: Beta-blockers
The AV node is particularly sensitive to these so the PR interval is usually _____________.
Act on Phase _____.
Partial agonists: (2)
Lacking local anesthetic effect: (2)
Low lipid solubility:
Combined alpha and beta blockade: (2)
Class 3 antiarrhythmics which also have Class 2 effects: (2)
Partial agonists: pindolol, acebutolol
Lacking local anesthetic effect: timolol, betaxolol
Low lipid solubility: atenolol
Combined alpha and beta blockade: carvedilol, labetalol
Amiodarone and sotalol
Class 3 antiarrhythmics act on phase ____.
Hallmark is the _________________ of the action potential duration.
ECG morphology shows increase in _____ interval.
Amiodarone (SimD: Dronedaron, Vernakalant)
The most efficacious of all antiarrhythmics.
Reserved for refractory arrhythmias due to many side effects (microcrystalline deposits in the cornea and skin, thyroid dysfunction -- hyper- or hypo- --, paresthesias, tremor, pulmonary fibrosis)
Has a long half-life of 3-10 weeks.
Class 4 antiarrhythmics
ECG shows a PR interval which is consistently _________________.
Verapamil (DOC for SVTs)
A miscellaneous antiarrhythmic with a short half-life (15 seconds) which is the drug of choice for paroxysmal supraventricular tachycardia