antiarrhythmic drugs Flashcards
what do class Ia do to action potential
lengthen action potential
example class Ia
disopyramide
what do class Ib do to action potential
shorten action potential
example of class Ib
lidocaine
what does class Ic do to action potential
no effect on action potential
example of Ic
flecainide
what does class II do
block beta-adrenoreceptors
example of class II
- atenolol
- bisoprolol
what does class III do to action potential
lengthen action potential
example of class III drug
amiodarone
sotalol
what does class IV do to action potential
reduce plateau phase of action potential
example of class IV
verapamil
diltiazem
how do class I drugs work
they reduce the rate of entry of sodium into the cell
what autonomic innervation do class II drugs affect
antisympathetic
what are most class II drugs
beta-adrenoreceptor antagonists
examples of selective beta blockers
- metoprolol
- bisoprolol
- atetnolol
what do beta blockers do to AV node conduction
suppress it
when are class II agents used
forms of SVT e.g. AF
how do class III agents work
delay potassium current
what can sotalol cause
- long QT syndrome
- torsades de pointes
what is vernakalant
multichannel blocker
what drugs are used for patients with structurally normal hearts
class Ic
what drugs are used for patients with structural heart disease
class III
what is employed in the treatment of symptomatic tachyarrhythmias
catheter ablation
how are ablations performed
percutaneously by placing electrode catheters into the heart chambers
usually via femoral vessels
what does successful ablation need
identification of site of origin
in what arrhythmias are catheter ablations used
- AV node re-entrant tachycardia
- AV re-entrant tachycardia with accessory pathway
- ventricular tachycardia
- atrial flutter
- atrial tachycardia
- paroxysmal atrial fibrillation
symptomatic patients with wolf parkinson white syndrome treatment
catheter ablation - 1st line
what is main risk associated with accessory pathway ablation
thromboembolism
what is recommended in patients with atrial flutter
catheter ablation
how does implantable cardioverter-defibrillation recognise
ventricular tachycardia or fibrillation and automatically delivers pacing or a shock to the heart
how many shocks does their battery last
100
are the ICD discharges painful
only if patient is awake
what is first line treatment for prevention of sudden death
ICD
