Arrhythmias Flashcards
(106 cards)
How common are arrhythmias
Pretty common
25% of pts treated with digoxin
50% of anesthetized pt
80% pts with acute MI
Do we normally treat arrhymias that are too fast or too slow?
Too fast
Tachy arrhythmia
Pros and cons of arryhmias
Can be life saving
On the other hand, there is a danger with antiarrhymic drugs in that they can paradoxically precipitate lethal arrhythmia in some patients
Where does the heart beat originate in
SA node
How does the beat travel
Goes from the SA node down the atria to the AV node
Gate keeper to the ventricles
AV
Which is worse, ventricular tachycardia or atrial tachycardia
Ventricular
What do we want to target when we treat atria?
AV node
What is the path of heart conduction
SA node, down atria, to AV node, purkinje, to ventricular
What does every step of conduction create?
AP
SA node AP
Hill
Atrial muscle AP
Steep AP
AV node AP
Hill
Perkinje AP
Steep
Ventricular muscle AP
Steep
Where do meds work for arrhythmia
On muscles and perkinje because of the steep AP
P waves
Atria gets excited
PR interval
Atrial conduction
SA node down to the AV node, span of atrial excitation
QRS interval
Ventricular being excited
Ventricular depolarization start
T wave
Ventricles repolarization
QT intervals
- ventricular depolarization to repolarization
- represents entire ventricular conduction
Fast response AP
Heart and Perkinje
Fast response in phase 0
Happen quickly, steep
What drugs do we use for fast response AP arrhymias?
Na channel blockers
K channel blockers