Antiarrhythmics

Question 1

Class IA antiarrhythmics

Answer 1

Disopyramide “Double” –> heart failure
Quinidine “Quarter” –> tinnitus and tornado de points
Procainamide “Pounder” –> SLE-like syndrome
can also cause thrombocytopenia

Question 2

Class IA MOA

Answer 2

inc AP duration
inc ERP
inc QT interval

Question 3

Class IA uses

Answer 3

atrial and vent arrhythmias

re-entrant and ectopic SVT and VT

Question 4

Class IB antiarrhythmics

Answer 4

Lidocaine "Lettuce"
Mexiletine "Mayo"
Tocainide "Tomato"
cause CNS stim/depression 
CV depression

Question 5

Class IB MoA

Answer 5

dec AP duration

prefers ischemic or depolarized Purkinje and vent tissue

Question 6

Class IB uses

Answer 6

acute vent arrhythmias –> best post MI

digitalis-induced arrhythmias

Question 7

Class IC antiarrhythmics

Answer 7

Moricizine "More"
Flecainide "Fries"
Propafenone "Please"
very pro-arrhythmic
contraindicated post mi

Question 8

Class IC MoA

Answer 8

prolongs refractory period in AV node

has a minimal affect on AP duration

Question 9

Class IC uses

Answer 9

SVT –> including A-fib

used as a last resort in refractory VT

Question 10

Class II antiarrhythmic

Answer 10

Beta blockers
dec SA and AV nodal activity
dec cAMP and Ca++ currents
dec slope of phase 4
AV sensitive --> inc PR interval

Question 11

Class II uses

Answer 11

SVT

slowing vent rate during atrial fib and flutter

Question 12

Class II toxicity

Answer 12

impotence / exacerbation of COPD and asthma
may mask signs of hypoglycemia
CI in cocaine users
treat overdose with glucagon

Question 13

Class III antiarrhythmics

Answer 13

K+ channel blockers "AIDS"
Amiodarone --> Class I, II, III, and IV effects; alters lipid profile
Ibutilide
Dofetilide
Sotalol

Question 14

Class III MoA

Answer 14

inc AP duration
inc ERP
inc QT interval

Question 15

Class III uses

Answer 15

a-fib and flutter
ventricular tachy (amiodarone and sotalol)

Question 16

Class III toxicity

Answer 16

Sotalol and Ibutilide –> torsade
Amiodarone –> a lot including pul fibrosis and hyper/hypo thyroidism
check PFTs, LFTs and TFTs before starting this drug

Question 17

Class IV antiarrhythmics

Answer 17

Ca++ channel blockers
Verapamil
Diltiazem

Question 18

Class IV MoA

Answer 18

dec conduction velocity
inc ERP
inc PR interval

Question 19

Class IV uses

Answer 19

prevention of nodal arrhythmias
rate control of a-fib
can cause flushing, edema, CV effects

Question 20

Adenosine

Answer 20

inc K+ out of cells
hyper polarize cells and dec intracellular Ca++
used in supraventricular tacky
short acting
flushing, hypotn, chest pain
effects blocked by theophylline and caffeine

Question 21

Mg++

Answer 21

effective in torsades and digoxin toxicity