Arrythmia Drugs DSA - Konorev Flashcards
class 1A drugs
quinidine
procainamide
disopyramide
class 1B drugs
lidocaine
mexiletine
class 1C drugs
flecainide
propafenone
General overview class 1A drugs
MOA and main effect
channels targeted
action potential
ECG effects
block sodium channels, slow impulse conduction, reduce automatism of ectopic pacemakers
preferentially bind to open (activated) sodium channels
-ectopic pacemaker cells with faster rhythms preferentially targeted
- block potassium channels
- prolong action potential duration
- prolong QRS and QT intervals of ECG
procainamide used to treat
sustained ventricular tachycardias, may be used in arrhythmias associated with MI
procainamide moa
directly depress SA and AV node activity
antimuscarinic activity
- ganglionblocking properties, reduces peripheral vascular resisatnce, m
- may cause hypotension
adverse effects of procainamide
QT prolongation
induction of torsade de pointes arrhythmias and syncope
excessive inhibtion of conduction
Lupus sydrome with arthritis, pleuritis, pulmonary disease, hepatitis, and fever
nausea, diarrhea
agranulocytosis
quinidine use
restore rhythm in atrial flutter/fibrillation pts with normal hearts
-sustained ventricular arrhythmia
quinidine and AV conductance
affords antimuscarinic effect on the heart which may enhance AV conductance
quinidine AE
may cause hypotension–>tachycardia
QT interval prolongation
induction of torsade de pointes and syncope
excessive slowing conduction throughout heart
diarrhea, nausea, vomiting
headache, dizziness, tinittus
thrombocytopenia, hepatitis, fever
disopyramide use
recurrent ventricular arrhythmias
potent antimuscarinic effect on heart
disopyramide AE
QT interval prolongation
induction of torsade de pointes and syncope
may precipitate heart fialure bc of neg inotropic effect
excessive depression of cardiac conduction
atropine like symptoms- urinary retention, dry mouth, blured vision, constipation, exacerbation of glaucoma
lidocaine blocks ___ sodium channels
inactivated
-selectively blocks conduction in depolarized tissue, making damaged tissue completely electirically silent
lidocaine use
in mono and polymorphic ventricular tachy
-very efficient in arrhythmias assocaited with acute MI
administration of lidocaine
IV bc of rapid first pass metabolism
AE of lidocaine
least toxic of all class 1 drugs
hypotension in pts with heart failure
paresthesias, tremor, slurred speech, convulsions
mexiletine clinical use
ventricular arrhytmias
releieve chronic pain, especially due to diabetic neuropathy and nerve injury
mexiletine AEs
tremor
blurred vision
nausea
lethargy
class 1B overview blocks what channel and in what state effect on what tissue efect on AP effect on potassium channel effect on QT
block sodium channels
bind to inactivated sodium channels (preferentially bind to depolarized cells)
no effect on conduction in normal tissue
may shorten AP
do not block postassium channels, and do not prolong AP or QT duration on ECG
Class 1C overview
blocks what, conduction effect
bind what channels
action on AP and QT
effect on QRS
block sodium channels, slow impulse conduction bind open (activated) sodium channels block certain potassium channels do not prolong action potential duration and QT intervatl duration on ECG prolong QRS interval duration
flecainide blocks
sodium and potassium channels
flecainide clinical use
in pt with normal hearts
treat supraventricualr arrhythmias including AF, paroxysmal SVT
life threatening ventricular arrhythmias like sustained ventricular tachy
AE of flecainide
may cause severe exacerbation of ventricular arrhytmias when administered to pts with
-preexisting vent tachys
pts with previous MI
pts with ventricular ectopic rhythms
propafenone posseses weak
weak B-blocking activity
propafenone use
to prevent paroxysmal AF and SVT in pts without structural disease
sustained vent arrhytmias
AE propafenone
exacerbation of ventricualr arrhythmias
metallic taste
constipation
don’t combine with CYP2D6 and CYP3A4 inhibtiors as risk of proarrhytmia may be incresaed
class 2 drugs overview
decrease SA node
decrease AV node
decrease Ca2+ overload, prevent delayed afterdepolarization
propranolol indicated for use in cardiac arrhythmias
arrhythmias associated with stress
re-entrant arrhythmias that involve AV node
A fib and a flutter
arrhthmias associated with MI (decrease mortalitly)
Esmolol DOA
short acting selective beta-1 blocker
use as continuous IV
esmolol clinical use
supraventricular arrhythmias
arrhytmias associated with thyrotoxicosis
myocardial ischemia or acute MI with arrhythmias
adjunct drug in gen anesthesia to control arrhythmias in perioperative period
PR interval in WPW and lown-ganong-levine syndrome
It is shortened
