Antiarrythmics

Question 0

Class I

Answer 0

Block fast Na channel in phase 0

IA- medium blockade
IB- minimal blockade
IC- maximal blockade

Question 1

Classes of antiarrythmics

Answer 1

I, IA, IB, IC
II
III
IV
Miscellaneous

Question 2

Class IA

Answer 2

Procainamide
Indicated for VT and torsades de pointes

Has proarrhythmic side effects

Adverse effects- lupus like syndrome, leukopenia, agranulocytosis

Question 3

Class IB

Answer 3

Lidocaine

Often used for less proarrhythmic potential than class IA

Frequently used for ventricular arryhythmias during surgery or after MI

Question 4

Class IC

Answer 4

Flecainide

High proarryhthmic potential so generally not used

Indicated for prevention of AF/AFL, PSVT and sustained VT

Clearance effected by urinary pH, acidic increases, basic declines

Question 5

Class II

Answer 5

Beta-blockers

Management of hypertension and post-MI
Caution in bronchospastic pt’s

end in “olol”

Question 6

Class III

Answer 6

Amiodarone/Dronedarone

Used for Vent, and supraventricular arryhthmias

May have life threatening interaction with other meds or induce pulmonary toxicity (IPF)

Question 7

Class IV

Answer 7

Calcium channel blockers (CCB’s)

Varapamil, diltiazem

Management of SV arrhythmias and ventricular rate control

Good alternatives to B blockers except for in CHF

Question 8

Miscellaneous

Answer 8

Digoxin (Lanoxin)

Prolongs refractory period

Second-line agent for AF

Adenosine (Adenocard)

Used to terminate SVT, 12 second half life (given through central line)

B blockers more effective