Cardiac Arrhythmia Drugs Flashcards
Name the types of cardaic arrhythmic drugs
Class IA, IB, IC - Na channel blockers
Class II - beta blockers
Class III - K channel blockers
Class IV - CCB
Adenosine
Vernakalant
Atropine
Digoxin
Ivabradine
Name some class IA antiarrhythmics and how they are given
Procainamide
Quinidine
Disopyramide
Given IV or PO
What cardiac effects do class IA antiarrhythmics have and how does this look on an ECG
Decreased conduction by decreasing phase 1/Na entery
Increased refractory by increased the AP duration and increasing Na channel inactivation
Decreased automacitiy by decreasing the slope of phase 4
Increased threshold
ECG: increased QRS, increased QT
What are class IA antihypertensives used for
Quinidine - maintain sinus rhythm in AF and atrial flutter, and prevents recurrence.
Procainamide - acute IV treatment of supraventricular and ventricular arrhythmias
What are the side effects of class IA antiarrhythmics
Hypotension
Decreased CO
Proarrhythmic
Insomnia
Seizure
GI effects
Lupus-like syndrome
Name some class IB antiarrhythmics and how they are given
Lidocaine - IV
What cardiac effects do class IB arrhythmics have and how does this appear on an ECG
Decreased AP duration
Decreased phase 0 conduction in fast beating/ischaemic tissue
Increased threshold
ECG: increased QRS in fast/ischaemic tissue
Name some uses of class IB arrhythmics
Acute - ventricular tachycarida
Not used in atrial arrhythmias or AV junctional arrhythmias
Name some side effects of class IB arrhythmics
Proarrhythmic - less than class IA
Dizziness
Drowsiness
Abdominal upset
Name some class IC antiarrhythmics and how they are given
Flecainide
Given PO or IV
What cardiac effects do class IC antiarrhythmics have and how does this appear on an ECG
Decreased phase 0
Increased threshold
Increased AP duration
Increased refractory period
ECG: increased PR, increased QRS, increased QT
Name some uses of class IC antiarrhythmics
Supraventricular arrhythmias
Premature ventricular contractions
Wolff-Parkinson-White syndrome
Name some side effects with the use of class IC antiarrhythmics
Proarrhythmic
Risk of sudden death
CNS and GI effects like other local anaesthetics
Increased ventricular response to supraventricular arrhythmias - flecainide flutter
Name some class II antiarrhythmics and how they are given
Propranolol - PO/IV
Bisoprolol - PO
Describe the cardiac effects of class II antiarrhythmics and how they affect the ECG
Increased refractory period - prolong plateau
Decrease phase 4 depolarisation
Increased AP duration and refractory period in AV node to slow conduction
ECG: increased PR, decreased HR
Name some uses of class II antiarrhythmics
Sinus and catecholamine depenedent tachycardia
Converting re-entrant arrhythmias at AV node
Protect ventricles from high atrial rate
Used following MI
Name some side effects from the use of class II antiarrhythmics
Bronchospasm
Hypotension
Name some class III antiarrhythmics and how they are given
Amiodarone - PO/IV
Sotalol - PO
Describe the cardiac effects of amiodarone and how this appears on an ECG
Increased refractory period
Increased AP duration
Increased threshold
Decreased phase 0 and conduction
Decreased phase 4
Decreased speed of AV conduction
ECG: decreased HR, increased PR, increased QRS, increased QT
Name some uses for amiodarone and name some side effects of its use
Effective for most arrhythmias
Serious side effects that increase with time, e.g. pulmonary fibrosis, hepatic injury, increased LDL, thyroid disease, photosensitivity, optic neuritis
Describe the cardiac effects of sotalol and how they appear on an ECG
Increased AP duration
Slow phase 4
Slow AV conduction
ECG: increased QT, decreased HR
Name some uses and side effects of sotalol
Uses: supraventricular and ventricular tachycardia
Side effects: proarrhythmic, fatigue, insomnia
Name some class IV antiarrhythmics and how they are given
Verapamil - PO/IV
Diltiazem - PO
Describe the cardiac effects of class IV antiarrhythmics and how they appear on an ECG
Slow conduction through the AV node
Increased refractory period in AV node - increased plateau phase of AP
Increased slope of phase 4 in SA node to slow HR
ECG: increased PR, increased or decreased HR
Name some uses and side effects of class IV antiarrhythmics
Uses: SVT, convert SVT
Caution when parital AV block as get asystole is beta-blocker also used
Caution when hypotensive, decreased CO or sick sinus syndrome
Side effect: GI upset
