Antiarrhythmic Drugs

Front 1

Where are Beta 1 receptors located (mostly)?

Back 1

the heart

Front 2

Where are Beta 2 receptors located (mostly)?

Back 2

vascular smooth muscle and bronchial smooth muscle

Front 3

Which class of antiarrhythmic drugs actually IMPROVES survival in patients with heart disease?

Back 3

Beta Blockers

Front 4

What are the main (intended) effects of beta blockers on the heart?

Back 4

Negative chronotropic, negative inotropic and negative dromotropic effects.

Front 5

What receptors are targeted by cardioselective beta blockers? Nonselective?

Back 5

Cardioselective: B1
Nonselective: B1 and B2 (some alpha)
Some have intrinsic sympathomimetic activity (can simultaneously stimulate and block beta receptors)

Front 6

Which beta blockers have Intrinsic Sympathomimetic Activity (ISA)? Which conditions would you want to use these for and which would you not want to use them for?

Back 6

Acebutolol and Pindolol; use in SA node dysfunction, don't use in HF and Angina

Front 7

What class of drug are the following and what is their selectivity? Atenolol, Metoprolol, Esmolol, Bisoproplol, Acebutolol

Back 7

Cardioselective beta blockers

Front 8

What class of drug are the following and what is their selectivity? Propranolol, Labetalol, Carvedilol, Pindolol, Nadolol

Back 8

Nonselective (B1, B2, some alpha) beta blockers

Front 9

Which specific beta blockers also block alpha receptors?

Back 9

Labetalol, Carvedilol

Front 10

What drugs can exacerbate severe Peripheral Vascular disease and Raynaud's syndrome?

Back 10

Nonselective (and sometimes even selective) beta blockers

Front 11

What are some conditions where beta blockers are contraindicated?

Back 11

Sinus bradycardia, patients with junctional escape rhythms, acute-decompensated HF, asthma, PVD/Raynaud's

Front 12

What are some conditions where beta blockers are indicated?

Back 12

Atrial tachyarrhythmias, heart failure (in most cases)

Front 13

What class of drugs are Diltiazem and Verapamil?

Back 13

Non- DHP CCBs

Front 14

What cells do Diltiazem and Verapamil have their efects on?

Back 14

Block Ca channels in SA and AV node (AV>SA)

Front 15

What are the effects of Diltiazem and Verapamil?

Back 15

Negative chronotropy, negative dromotropy, negative inotropy

Front 16

What are some indications for CCBs (Diltiazem and Verapamil)?

Back 16

Slows ventricular response during atrial tachyarrhythmias (Atrial Flutter, Atrial Fibrillation, Atrial tachycardia) and interrupts reentrant loops involving AV Node (AV Node Reentry, AV Reentrant Tachycardia)

Front 17

What are the adverse effects of CCBs (diltiazem and verapamil)- situations where they would be contraindicated?

Back 17

Too much negative chronotropy- bad in patients w/ sinus node dysfunction or junctional escape rhythms; too much negative dromotropy- can cause an AV block; too much negative inotropy- bad in patients with SHF; hypotension, peripheral edema, drug interactions. See these effects more @ high doses.

Front 18

Which antiarrhythmic drug is also referred to as a "cardiac glycoside"?

Back 18

Digoxin

Front 19

What are the main intended effects of digoxin?

Back 19

positive inotropy (increases intracellular Ca), antiarrhythmic (via augmenting vagal tone)--> primary target is slowed conduction in AV node, usu doesnt have big fx on SA node

Front 20

How does digoxin compare to diltiazem and verapamil?

Back 20

Much less effective in controlling AV nodal conduction, narrow TI, almost never best 1st choice for arrhythmia

Front 21

What are some symptoms of digoxin toxicity?

Back 21

N/V, visual disturbances, monitor kidney function, AV block, ventricular tachyarrhythmias (causes delayed afterdepolarizations)

Front 22

What is the primary purpose of adenosine administration? How is it administered and how long does it last?

Back 22

Primary purpose: first line for terminating any reentry involving the AV node- performs an AV nodal block. Administered as a rapid IV push and cleared very quickly (10s half life).

Front 23

what are some possible contraindications for Adenosine?

Back 23

Can prescipitate brochospasm in asthmatics; rarely can precipitate afib

Front 24

What class of antiarrhythmics are Beta blockers?

Back 24

Class 2 Antiarrhythmics

Front 25

What class of antiarrhythmics are CCBs?

Back 25

Class 4 Antiarrhythmics

Front 26

What class of antiarrhythmics are Na+ channel blockers?

Back 26

Class 1 antiarrhythmics

Front 27

What class of antiarrhythmics are K+ channel blockers?

Back 27

Class 3 antiarrhythmics

Front 28

What are the major effects of Class 1 antiarrhythmics (Na+ channel blockers)? Good and bad

Back 28

BLOCKS Na CHANNELS: slower automaticity and slower conduction velocity, +/- effects on reentry; CAN STOP AFIB! (convert it to sinus rhythm)- these drugs are Use Dependent (faster HR--> more Na channel blockade)

Front 29

What is a major contraindication for Class 1 antiarrhythmics?

Back 29

Patients w/ prior MI- unless they have an ICD (bc can get incessant VT)

Front 30

What class and subclass are the following drugs: Quinidine, Procainamide, Disopyramide

Back 30

Class 1A antiarrhythmics- these are older drugs and are not used much

Front 31

What class and subclass are the following drugs: Lidocaine, Mexiletine

Back 31

Class 1B antiarrhythmics: these end with "ine"

Front 32

What class and subclass are the following drugs: Flecainide, Propafenone

Back 32

Class 1C antiarrhythmics- these have the strongest effect on Na channels
All have an "f" in the name

Front 33

What are the major effects of the class 1A antiarrhythmics (Quinidine, Procainamide, Disopyramide)?

Back 33

Prolong QRS and QT (block K+ channels too), and have lots of side effects

Front 34

What are the major effects of the class 1B antiarrhythmics (Lidocaine, Mexilitine)?

Back 34

Shorten QT, preferentially target ischemic tissue, only work on ventricular cells

Front 35

What are the major effects of Class 1C antiarrhythmics (Flecainide and Propafenone)?

Back 35

Most potent, prolong QRS most, no direct effect on QT, negative inotropes

Front 36

When would Class 1C antiarrhythmics be contraindicated?

Back 36

Heart failure- because they are negative inotropes.

Front 37

What are some side effects of Propafenone?

Back 37

Beta blocking properties (mnemonic: "propafenone breaks down proproanolol"), mild CNS symptoms (dizziness)

Front 38

What is meant by Reverse Use Dependence in K+ channel blockers?

Back 38

Work better during slower heart rates, which means they are not as effective on Afib as Na channel blockers.

Front 39

What class of drug is Sotalol?

Back 39

Class 3 antiarrhythmic- a K+ channel blocker

Front 40

What class of drug is Amiodarone?

Back 40

Class 3 antiarrhythmic- a K+ channel blocker

Front 41

What class of drug is Dronedarone?

Back 41

Class 3 antiarrhythmic- a K+ channel blocker

Front 42

What class of drug is Dofetilide/Ibutilide?

Back 42

Class 3 antiarrhythmic- a K+ channel blocker

Front 43

Can K+ channel blockers be used in patients with AMI?

Back 43

Yes

Front 44

What is a major risk with K+ channel blockers?

Back 44

Torsades (polymorphic VT) due to QT prologation. More likely w/ too much drug, hypokalemia, and bradycardia (reverese use dependence)

Front 45

Which K+ channel blocker has the lowest risk for Torsades?

Back 45

Amiodarone (don't have to monitor QT).

Front 46

What compound is responsible for most of the toxicity we see with amiodarone?

Back 46

Iodine. Think "iod" in amiodarone.

Front 47

Where is Sotalol cleared?

Back 47

kidney- can accumulate in renal failure

Front 48

Where are Dofetilide and Ibutilide cleared?

Back 48

liver and kidney

Front 49

What activity does Sotalol have besides K+ channel blockade?

Back 49

Beta blocker activity

Front 50

Which K+ channel blocker is fairly safe in heart failure and why?

Back 50

Dofetilide because it is not a negative inotrope

Front 51

What are the major toxicities of Amiodarone?

Back 51

Corneal deposits, hypo/hyperthyroidism, hepatic injury, pulmonary toxicity, skin photosensitivity (blue), interaction w/ warfarin. "blue, blind and coughing up your thyroid and liver"

Front 52

What is the most dangerous toxicity of Amiodarone?

Back 52

Pulmonary toxicity- after about 10 years of dosing.

Front 53

Which K+ channel blocker would you not want to give to young patients?

Back 53

Amiodarone

Front 54

Which K+ channel blocker has multiple MOA and can be used for just about every arrhythmia?

Back 54

Amiodarone

Front 55

Which K+ channel blocker is just like Amiodarone w/out iodine and thus w/out a lot of the side fx?

Back 55

Dronedarone

Front 56

Which antiarrhythmics are contraindicated in SHF?

Back 56

Verapamil and diltiazem (class 4, CCBs) and type 1 antiarrhythmics (unless you already have an ICD)

Front 57

Which antiarrhythmics are contraindicated w/ prior MI?

Back 57

Type 1 antyarrhythmics