Drugs For Cardiac Arrhythmias (Konorev) Flashcards Preview

Cardiovascular Medicine-Unit 2 > Drugs For Cardiac Arrhythmias (Konorev) > Flashcards

Flashcards in Drugs For Cardiac Arrhythmias (Konorev) Deck (43):
1

What are the 1B Na channel blocking drugs?

Lidocaine
Mexiletine

2

Which cell types have a fast AP?

Ventricular contractile cardiomyocytes
Atrial cardiomyocytes
Purkinje fibers

3

Which cell types have a slow (pacemaker) AP?

SA node cells
AV node cells

4

What are the 1C Na channel blocking drugs?

Flecainide
Propafenone

5

What are the class 2 antiarrhythmic drugs?

Beta blockers
Esmolol and propanolol

6

What are class 3 antiarrhythmic drugs?

K channel blocking drugs
Amiodarone
Dronedarone
Sorta lol
Dofetilide
Ibutilide

7

What are class 4 antiarrhythmic drugs?

Cardioactive Ca channel blockers
Verapamil and Diltiazem

8

Class 1A drugs preferentially bind to __ channels

Open (activated) Na

9

Class 1A drugs have what effects on the following:

-K channels: ___
-AP duration: ___
-QRS and QT intervals: ___

Block

Prolong

Prolong

10

This 1a drug is used to tx sustained V tach, directly depresses the activities of SA and AV nodes, and possesses antimuscarinic activity

Procainamide

11

What are adverse effects of Procainamide?

Cardiac --> QT prolongation, induce Torsade de pointes and syncope

Extracardiac --> lupus syndrome, nausea, diarrhea, and agranulocytosis

12

This 1a drug is a natural alkaloid from Cinchona bark that is used occasionally for restoring rhythm in A flutter/fib pts with normal (but arrhythmic) hearts

Quinidine

13

What are adverse effects of quinidine?

Cardiac --> QT prolongation, induce Torsades

Extracardiac --> GI side effects, headache, dizziness, tinnitus, thrombocytopenia, hepatitis, fever

14

This 1a drug is used for tx of recurrent V Tac

Disopyramide

15

What are adverse effects of Disopyramide?

Cardiac --> QT prolongation, induce torsades, negative inotropic effect

Extracardiac --> atropine-like symptoms

16

Class 1B drugs bind to ___ channels

Inactivated Na , preferentially bind to depolarized cells

17

This 1B drug blocks inactivated Na channels-selectively blocks conduction in depolarized tissue, making damaged tissue completely "electrically silent". It is used in mono- and polymorphic V Tac

Lidocaine: extensive 1st pass metabolism and only by IV route

This is the least toxic of all Class I drugs

18

__ is an orally active 1B drug used for ventricular arrhythmias, to relieve chronic pain (esp pain d/t diabetic neuropathy and nerve injury)

Mexiletine

Adverse effects: tremor, blurred vision, nausea, lethargy

19

Class 1C drugs block Na channels to slow impulse conduction and preferentially bind to __ Na channels

Open (activated)

They also block certain K channels

20

What do 1C drugs do to the QRS complex?

Prolong QRS

21

This 1C drug blocks Na and K channels and has no antimuscarinic effects. It is used to tx pts with normal hearts, supraventricular arrhythmias including AF, paroxysmal SVT (AVNRT, AVRT).

Flecainide

22

This 1C drug possesses weak B-blocking activity and used to prevent paroxysmal AF and SVT in pts without structural disease and also used in sustained ventricular arrhythmias

Propafenone

23

What are some adverse effects of Propafenone and what should you no combine with?

Exacerbates ventricular arrhythmias
Metallic taste
Constipation

Do NOT combine with CYP2D6 and CYP3A4 inhibitors as risk of proarrhythmia may be increased

24

What effects do class 2 drugs have on the following:

-SA node: ___
-AV node: ___
-Ventricular myocardium: ___

SA node: decrease HR (Increase RR interval)
AV node: decrease AV conductance (Increase PR interval)
Ventricular myocardium: decrease Ca overload, prevent delayed after-depolarizations

25

What are clinical indications for Propanolol (class 2)?

Arrhythmias associated with stress
Re-entrant arrhythmias that involve the AV node
A fib and flutter
Arrhythmias associated with MI

26

This class 2 drug is a selective B1 blocker with a short half life (10 min) on continuous IV fusion

Esmolol

27

What effects do Class 3 drugs have on the following:

-AP: ___
-QT interval: ___
-Refractory period:___

Prolong AP duration

Prolong QT interval

Prolong refractory period

28

This class 3 drug blocks K and inactivated Na channels, prolongs QT interval and APD uniformly over wide range of HR's. It possesses adrenolytic activity, has Ca channel blocking activities, cuases bradycardia and slows AV conduction. It can also cause peripheral vasodilation and is used to Tx ventricular arrhythmias

Amiodarone

29

Amiodarone is metabolized by ___

CYP3A4

1/2 life affected by drugs that inhibit CYP3A4 (Cimetidine) or induce it (Rifampin)

30

What are some adverse effects of Amiodarone?

Cardiac --> AV block and bradycardia

Extracardiac --> fatal pulm fibrosis, hepatitis, photodermatitis, depositis of drug in cornea and other eye tissues, blocks peripheral conversion of thyroxine to triiodothyronine

31

This class 3 drug blocks multiple K channels, blocks Na current, blocks L-type Ca current, and has stronger antiadrenergic effects than Amiodarone

Dronedarone

32

What is the Black box warning for Dronedarone?

Increases risk of mortality in pts with decompensated HF (Class IV) and in pts with a recent decompensation of HF requiring hospitalization

33

This drug is a class 2 (non-selective B blocker) and class 3 agent (prolongs APD). It is used to tx life-threatening ventricular arrhythmias and maintenance of sinus rhyth in pts with A fib.

Sorta lol

34

What are adverse effects of Sotalol?

Depress cardiac function
Provoke Torsades

35

This class 3 drug specifically blocks rapid component of delayed rectifier K current. It has a very narrow therapeutic window and used to convert AF to the sinus rhythm and maintain sinus rhythm after cardioversion.

Dofetilide

36

What are adverse effects of Dofetilide?

QT prolongation and increased risk of ventricular arrhythmias

37

What effects do Class 4 drugs have on the following:

-Slope of phase 0 depolarization: ___
-SA node depolarization: ___
-AV node conduction time: ___
-AP duration and refractory period in AV node: __

Decrease slope of phase 0 depolarization
Slow SA node depol., causing bradycardia
Prolong AV node conduction time
Prolong AP duration and refractory period in AV node

38

What are clinical uses of Diltiazem?

Prevention of paroxysmal SVT
Rate control in A fib and A flutter

39

What are adverse effects of class 4 drugs?

Cardiac --> negative inotropy, AV block, SA node arrest, bradyarrhythmias, hypotension

Extracardiac--> constipation (Verapamil)

40

This drug activates K current and inhibits Ca funny currents, causing marked hyperpolarization and suppression of APs in pacemaker cells. It inhibits AV conduction and increases nodal refractory period. It is used clinically to convert sinus rhythm in paroxysmal SVT

Adenosine

41

What are adverse effects of adenosine?

SOB
Bronchoconstriction
Chest burning
AV block
Hypotension

42

Which antiarrhythmic drug classes can cause long QT syndrome and torsade de pointes arrhythmias?

Class 1a and 3

43

What are the 1A Na channel blocking drugs?

Quinidine
Procainamide
Disopyramide