Antiarrythmics

Question 1

Sodium channel blockers (class I)

Answer 1

slow or block conduction(esp in depol cells).

dec slope of phase 0 depol.

State dependent (selectively depress tissue that is frequently depol)

Question 2

Class 1a list

Answer 2

Quinidine, Procainamide, Disopyramide

“The Queen Proclaims Diso’s Pyramid.”

Question 3

Class I MOA

Answer 3

increase: AP duration, effective refractory period in ventricular action potential, QT interval

Question 4

Class I use

Answer 4

atrial and ventricular arrhythmias (esp. re-entrant and ectopic SVT and VT)

Question 5

Class I ADR

Answer 5

thrombocytopenia, torsades de pointes due to inc QT interval

Question 6

quinidine ADR

Answer 6

cinchonism (HA, tinnitus)

Question 7

procainamide ADR

Answer 7

reversible SLE-like sx

Question 8

disopyramide ADR

Answer 8

heart failure

Question 9

Class 1b list

Answer 9

Lidocaine, Mexiletine

Phenytoin can be classified here

Question 10

Class 1b MOA

Answer 10

dec AP duration.

preferentially affect ischemic or depol. Purkinje and ventricular tissue

Question 11

Class 1b use

Answer 11

acute ventricular arrhythmias (esp post MI)

digitalis-induced arrhythmias

Question 12

Class 1b ADR

Answer 12

CNS stimulation/depression, CV depression

Question 13

Class 1C list

Answer 13

flecinide, propafenone

Question 14

Class 1c MOA

Answer 14

significantly prolongs ERP in AV node and accessory bypass tracts.

no effect on ERP in Purkinje and ventricular tissue.

minimal effect on AP duration

Question 15

Class 1C use

Answer 15

SVTs, including afib

only as last resortin refractory VT

Question 16

Class 1C contraindications

Answer 16

proarrhythmic, esp post-MI (contraindictated)

structural and ischemic heart disease

Question 17

Antiarrhythmics Class II (BB) list

Answer 17

metoprolol, propranolol, esmolol, atenolol, timolol, carvedilol

Question 18

BB MOA

Answer 18

dec. SA and AV nodal activity by dec cAMP, Ca currents.

Suppress abnormal pacemakers by dec slope of phase 4

AV node particularly sensitive, inc. PR interval.

Question 19

BB use

Answer 19

SVT, ventricular rate control for afib and atrial flutter

Question 20

BB ADR

Answer 20

impotenence; exacerbation of COPD and asthma; bradycardia/AV block/HF; sedation, sleep alterations; may mask sx of hypoglycemia

Question 21

Metoprolol ADR

Answer 21

dyslipidemia

Question 22

Propanolol ADR

Answer 22

exacerbate vasospasm in prinzmetal angina

Question 23

BB contraindications

Answer 23

pheochromocytoma, cocaine toxicity

cause unopposed a1-agonism if given alone

Question 24

BB OD tx

Answer 24

saline, atropine, and glucagon

Question 25

Antiarrhythmics Class III (KCl channel blockers) list

Answer 25

amiodarone, ibutilide, dofetilide, sotalol | "AIDS"

Question 26

KCl channel blockers MOA

Answer 26

increased: AP duration, ERP, QT interval

Question 27

KCl channel blockers use

Answer 27

afib, atrial flutter

Question 28

Amiodarone, sotalol use

Answer 28

ventricular tachycardia

Question 29

Sotalol ADR

Answer 29

torsades de pointes, excessive B blockade

Question 30

Ibutilide ADR

Answer 30

torsades de pointes

Question 31

Amiodarone ADR

Answer 31

***check PFTS, LFTS, TFTS**** pulmonary fibrosis, hepatotox, thyroidism, corneal deposits, blue/gray skin deposits resulting in photodermatitis, neuro effects, constipation, bradycardia/heart block/HF

Question 32

Why is amiodarone special?

Answer 32

lipophilic, has class I-IV effects

Question 33

Antiarrhythmics Class IV (Ca channel blockers) list

Answer 33

verapamil, diltiazem

Question 34

Ca Channel blockers MOA

Answer 34

dec conduction velocity | inc ERP, PR interval

Question 35

Ca channel blockers use

Answer 35

prevention of nodal arrhythmias (eg SVT) | rate control in afib

Question 36

Ca channel blockers ADR

Answer 36

constipation, flushing, edema, HF/AV block/sinus node depression

Question 37

Other antiarrythmics

Answer 37

adenosine, MG

Question 38

adenosine MOA

Answer 38

inc K+ out of cells --> hyperpolarizing the cell and dec Ica

Question 39

Adenosine use

Answer 39

dx/terminating certain forms of SVT (very short acting)

Question 40

Adenosine antagonists

Answer 40

theophylline, caffeine

Question 41

Adenosine ADR

Answer 41

flushing, hypotension, chest pain, sense of impending doom, bronchospasm

Question 42

Mg2+ use

Answer 42

effective in torsade de pointes and digoxin toxicity