Antiarrthymics

Question 1

Class I works how

“No Bad boy Keeps Clean”

Answer 1

Na channel blockers; phase 0

• increase in effective refractive period
• all these phases referring to ventricular

Question 2

Class II works how

Answer 2

Beta blocker; phase 4

Question 3

Class III works how

Answer 3

K channel blocker; phase 3

*increase in ERP, prolongs the AP duration

Question 4

Class IV works how

Answer 4

Ca channel blocker; phase 0

• increase in effective refractive period

Question 5

Class 1A examples (3)

“Double Quarter Pounder”

Answer 5

1. Disopyramide
2. Quinidine
3. Procainamide

Question 6

procainamide used for what? main tox?

Answer 6

WPW; drug induced SLE

“SHIPP”

Question 7

3 AEs of quinidine

Answer 7

1. cinchonism (HA, dizziness, tinnitus)
2. thrombocytopenia
3. ↑ QT (torsades)

Question 8

3 IB examples (prob most used)

“Mayo, Lettuce, Tomato”

Answer 8

1. Mexilitine
2. Lidocaine
3. Tocainide

Question 9

what are three main uses for lidocaine

Answer 9

1. acute ventricular tachycardia
2. digitalis-induced arrythmia
3. tachcardia post-MI

*1B are best post MI !!–> preferentially affect ischemic ventricular tissue

Question 10

2 class 1C examples

“ Fries Please”

Answer 10

1. Flecainide

2. Propafenone

Question 11

What 2 instances are class IC absolutely contraindicated

Answer 11

1. structural heart dz

2. post-MI

Question 12

main use of 1C

Answer 12

LAST RESORT in refractory tachyarrhythmias

Question 13

main uses of class II (beta blocker) as anti arrhythmics (2)

Answer 13

slowing ventricular rate during:

1. atrial fibrillation
2. atrial flutter

*also v-tach and SVT

Question 14

Which beta blocker is contraindicated in Prinzmetal/s angina

Answer 14

propanolol –> can exacerbate angina

Question 15

4 examples of class III

“AIDS”

Answer 15

1. Amiodarone
2. Ibutilide
3. Dofetilide
4. Sotalol

*also Bretylium

Question 16

main AE with all class III?

Answer 16

Torsades–> all prolong the QT

Question 17

5 main AEs of amiodarone

Answer 17

1. Pulmonary fibrosis
2. Hepatotoxicity
3. Hypo/ hyperthyroidism (is 40% iodine by weight)
4. Photosensitivity
5. Blue/ grey skin

• also risk of bradycardia or heart block or CHF; this is what they are used for though–> slow heart down
• amiodarone has class I, II, III, and IV effcts b/c it alters the lipid membrane

Question 18

2 examples of Class IV

Answer 18

Verapamil and diltiazem–> these are the non-DHP CCBs, which have effects on the heart

Question 19

main use of class III

Answer 19

used when others fail; rhythm control in a-fib; amiodarone used in WPW

Question 20

what is a main use for Class IV

Answer 20

prevention of nodal arrhythmias (SVT)

Question 21

5 AE of non-DHP CCBs?

Answer 21

1. constipation
2. flushing
3. edema
4. CV (CHF, heart block, sinus node depression)
5. Torsades

Question 22

What AEs do prob ALL antiarrhythmics share

Answer 22

torsades, CHF, heart block, bradycardia–> they are all used to slow heart function so it makes sense