Antiarrhythmics part 4

Class Ic is a ____ Na-channel blocker.

potent

It takes Class Ic drugs ____ seconds to recover

10

What class does Fleccainide belong to?

Class Ic drug

What is the brand name for Flecainide?

Tambocor

Flecainide blocks K and L-type Ca channels ___.

to a lesser extent

Flecainide works better in ______ than ____ and works in normal HR

fast HR
slow HR

_____ can prolong QRS and QT interval

Flecainide

Flecainide is eliminated through _____

hepatic and renal systems

Flecainide is metabolized by _____

CYP2D6 and CYP1A2

Adverse effects of Flecainide

proarrhythmic, CHF exacerbation, and heart block

Contraindications of Flecainide

secondary/tertiary AV block or right bundle branch block

What is the brand name of Propafenone

Rythmol

Propafenone is a part of the _____ class.

Ic

Propafenone is very efficient in maintaining _____ rhythm.

sinus

Propafenone has moderate efficacy in___.

ventricular arrhythmias

Propafenone is structurally ____.

racemic

____ is also a beta-adrenergic blocker

S+propafenone

At normal HR, propafenone prolongs ____.

PR, QRS intervals

Propafenone is eliminated by ___.

H

Propafenone is metabolized by ___.

CYP2D6

Main adverse effect of Propafenone is ____.

proarrhythmic (ventricles), bradycardia and bronchospasm due to the beta-blocking

Contraindications for use of Propafenone is ____.

any heart conditions

Dysopyramide is part of which class?

Ia

The brand name for Dysopyramide is ____.

Norpace

Class Ia have ____

intermediate recovery time ranging from 1-10 seconds

Dysopyramide blocks _____

Na and Ca channels

When Dysopyramide blocks Na channels, it ____.

increases threshold potential and decreased automaticity

When Dysopyramide blocks K channels, it ____.

prolongates the action potential (especially seen in slow HR)

Dysopyramide also inhibits the _____.

vagal nerve

Dysopyramide is eliminated through ____.

H/R (50%)

Dysopyramide is metabolized by ____

CYP3A4

Adverse effects of Dysopyramide include: ___

proarrhythmic effects (TDP), and anticholinergic effects (dry mouth, constipation, urinary retention, precipitation of glaucoma)

Contraindications for Dysopyramide:

secondary/tertiary AV block

Lidocaine is a ____

class Ib antiarrhythmic

Class Ib has ____ of recovery time.

<1s

Lidocaine is considered to have ____ potency and not useful for _____.

weak
atrial arrhythmias

Effects of Lidocaine are seen in ___ HR and ____ (ischemic) tissues

fast
depolarized

Lidocaine increases the ____.

threshold potential

Lidocaine is also seen reducing the _____.

Phase 4 slope

Lidocaine doesn't usually change ____

PR and QRS intervals, but may shorten QT interval

Lidocaine's brand name is:

Xylocaine

Lidocaine is eliminated through ____

H/R

Lidocaine is metabolized by ____.

CYP3A4

Lidocaine can cross the ____

BBB and placenta

Adverse effects from Lidocaine

seizures (large, rapid IV doses), tremor, dysarthria, nystagmus (involuntary jerking of the eye => early sign of toxicity)

Use lidocaine cautiously in ___

liver/heart failure, AV conduction deficit

Mexiletine is a ____.

class Ib drug

The brand name of Mexiletine is ____

Mexitil

Mexiletine is also a ___ Na-channel blocker and has a very short recovery time.

weak

Mexiletine is _____ used in ventricular arrhythmias.

rarely

Mexiletine is structurally similar to ____ and suitable for chronic oral therapy due to less FPM.

lidocaine

Mexiletine is eliminated through ____.

H/R (10%)

Use mexiletine cautiously in ____

H/R patients

Mexiletine is metabolized by ____.

CYP1A2 and CYP2D6

Main adverse effects of Mexiletine ____.

proarrhythmic effects, exacerbation of HF, upper GI distress (may mean toxicity), lightheadedness, tremor, and coordination difficulties