Cardio: Anti-Arrythmic Drugs Flashcards
What do class 1 drugs act on? Which phase of the action potential is this?
Voltage activated sodium channels
Phase 0
Which drug is an example of a class 1A anti-arhythmic drug?
Quinidine
Disopyramide
Which drug is an example of a class 1B anti-arhythmic drug?
Lignocaine
Which drug is an example of a class 1C anti-arhythmic drug?
Flecainide
What are class 1 anti-arhythmic drugs used to treat?
Paroxysmal AF
Prevention of ventricular tachycardia
Which class 1 drug is given to manage rhythm in chronic AF where there is no underlying heart disease?
Flecainide
Which class 1 drug is given post MI to prevent ventricular tachycardia/fibrillation?
Lignocaine
‘Say no to ventricular tachycardia’ - ligNOcaine
Which drugs are class 2 anti-arhythmic drugs?
Beta-blockers
How do class 2 drugs work?
Counter elevated sympathetic activity
Increase refractory period
Decrease firing of SA node
What are beta-blockers used to treat?
Rate control in AF
Persistent sinus tachycardia
What are the main side effects of beta-blockers?
Bronchospasm Cold peripheries Hypoglycaemia Lethargy Aggravation of HF Bradycardia
Which phase of the action potential do beta-blockers work on?
Phase 0
What do class 3 drugs work on? Which phase of the action potential is this?
Voltage activated potassium channels
Phase 3
Which drugs are example of class 3 anti-arrythmics?
Amiodarone
Stall
How do class 3 drugs affect the action potential?
Prolong the action potential
Increase refractory period
What is amiodarone used to treat?
Ventricular tachycardia
WPW syndrome
Rhythm control in AF patients with underlying heart disease
Atrial flutter
What is sotalol used to treat?
Paroxysmal SVTs
What are the main side affects of amiodarone?
Blue/slate grey skin
Thyroid abnormalities
Pulmonary fibrosis
What type of drug are class 4 anti-arhythmic drugs?
Calcium channel blockers
Which phase of the action potential do class 4 drugs act on?
Phase 2
Which type of calcium channel blocker is preferred in the treatment of arrhythmias?
Drugs selective for cardiac L type calcium channels, e.g. verapamil
When is verapamil contraindicated?
In conjunction with beta blockers
WPW syndrome
When is verapamil used?
Rate control in AF
SVT once vagal manœuvres + adenosine fail
How is a ventricular tachycardia due to hypokalaemia treated?
IV magnesium sulphate
