cardiac meds Flashcards
class Ia anti-arrhythmic - what receptor - what does it do
- NaCh blocker
- inhibits conduction (esp in depolarized cells) by decreasing slope of phase 0 and increasing threshold for firing in abnormal pacemaker cells …
- this increases AP duration and the effective refractory period
class Ia anti-arrhyhtmic examples (3)
- Disopyramide
- Quinidine
- Procainamide
class Ia anti-arrhythmic toxicity (5)
- cinchonism (Queen)
- reversible SLE-like (Procainamide)
- HF (disopyramide)
- QT prolongation –> TdP
- Thrombocytopenia
class Ib anti-arrhythmic
- what receptor
- what does it do
- NaCh blocker in ischemic or depolarized Purkinje/ventricular tissue
- decreases AP duration
uses of class Ia anti-arrhythmics (2)
- atrial arrhthmia
- ventricular arrhythmia
especially re-entrant and ectopic SVT and VT
uses of class Ib anti-arrhythmics (2)
- acute ventricular arrhyhtmia (esp post MI)
- dig-induced arrhythmia
Ib anti-arrhythmic toxicity (3)
- CNS depression
- CNS stimulation
- CV depression
examples of Ib anti-arrhyhmics (2)
- Lidocaine
- Tocainide
- Mexiletine
“Lettuce Tomatos and Mayo”
Ic anti-arrhyhtmic mechanism
prolongs refractory period in AV node
minimal effect on AP duration
Ic anti-arrhythmic uses (3)
- SVT
- A-fib
- Last resort refractory VT
Class II anti-arrhyhtmic
- what does it do? (3)
beta blocker
in nodal cells
- decrease SA and AV nodal activity by decreasing cAMP and Ca
- decreases slope of phase 4
- increases PR interval
examples of Ic anti-arryhtmics (2)
- Moricizine
- Flecainide
- Propafenone
“More Fries Please”
uses of class II anti-arrhythmics (2)
- SVT
- slowing ventricular response during A-fib or flutter
short acting beta blocker?
esmolol
class II anti-arryhtmic toxicity (6)
- Sex :impotence
- Pulm: exacterbation of COPD asthma
- CV: brady, AV block, CHF
- CNS: sedation, sleep alteration
- Endo: metop can cause dyslipidemia
- propranolol can exacerbate Printzmetal aginga
treat class II anti-arrhythmic overdose with what?
glucagon
class III anti-arryhtmic
- what does it do? (4)
- what receptor
KCh blocker in non-nodal fibers
- incresaes AP duration
- increases refractory period
- increases QT interval
- used when other anti-arrhythmics fail
ex class II anti-arryhtmic (6)
- metoprolol
- propranolol
- esmolol
- atenolol
- timolol
- carvedilol
use of class III anti-arryhtmic (3)
- a-fib
- a-flutter
- VT
ex of class III anti-arrhytmic (4)
- Amiodarone
- Ibutilide
- Dofetilide
- Sotalol
AIDS blocks potassium
class III anti-arryhtmic toxicity (2)
- TdP: sotalol, ibutilide
- Amio: lungs, liver, thyroid
which drug has class I, II, III, IV effects
how?
amiodarone
by altering lipid MB
clas IV anti-arrhythmic
- receptor
- mechanism (3)
- CaCh blocker
- decreases conduction velocity in nodal cells
- increases PR interval
- increases refractory period
class IV anti-arryhthmic uses (2)
- prevent nodal arrhyhtmia (SVT)
- rate control in A-fib
class IV anti-arrhyhtmic toxicity (4)
- constipation
- flushing
- edema
- CV: CHF, AV block, sinus node depression
examples of class IV anti-arrhythmic (2)
- Verapamil
- Diltiazem
Adenosine
- mechanism
- used for?
- increases K out of cell –> hyperpolarize -> decrease Ca current
- used for dx/abolishing SVT b/c short term (15sec)
how does adenosine effects last?
15 seconds
Adverse effects of adenosine (3)
- flushing
- hypotension
- chest pain
Mg in cardiac pharamcology
effective in TdP
and
dig toxicity
