Anti-Arrhythmics Flashcards
what is the most common atrial arrhythmia that we use antiarrythmics for?
atrial fibrillation
what does inappropriate rate/timing of cardiac muscle contraction lead to?
decreased CO
where do most anti-arrhythmic drugs work?
on channels in cell membrane
what phase do Na+ channel blockers work on? what class is of drug is this?
phase 0 = depolarization
class 1
what class of drug antagonizes sympathetic input to pacemaker cells, decrease SAN and ectopic automaticity and prolongs refractory period of the AVN?
Class 2
what are class 2 drugs known as?
Beta Blockers
what do class 2 drugs do?
decrease ventricular responsiveness to atrial tachyarrhythmias
what are class 3 drugs known as?
K channel blockers
what do class 3 drugs do?
keep K inside cell
prolong repolarization
what phase does repolarization take place?
3
what phase does Ca influx take place?
phase 2
what are the class 4 drugs known as?
Ca channel blockers
what do class 4 drugs do?
slow AVN conduction
what is a drug that is a multi-channel blocker?
vernakalant
what do fast AP depend on?
Na channels
what do slow AP depend on?
Ca channels
where are Na channels found? (3)
his/perkinje
atrial myocytes
ventricular myocytes
where are Ca channels found? (2)
SA node
AV node
what type of arrhythmia are Ca channel blockers good for?
atrial fibrillation
what type of arrhythmias are Na channel blockers good for?
ventricular arrhythmias
what do many AAD do to the QT interval?
increase
what does an increased QT interval predispose a patient to?
torsades de pointes
polymorphic ventricular tachycardia
torsades de pointes
multiple foci of reentrant pathways that cause rapid and disorganized atrial depolarization that are blocked to various degrees at the AV node
atrial fibrillation
a patient that presents with palpitations, SOB, dizziness, a slow ventricular response, and ventricular rate of 120-180 bpm
only a small number of conductions are transmitted through the AV node
atrial fibrillation
what are the AV node blockers that I should use for atrial fibrillation?
CCBs
BB
digoxin
amiodarone
on which patients should we prioritize rate control?
elderly
