PHARMACOLOGY OF RHYTHM CONTROL Flashcards
what classification is used for antiarrythmics?
vaughan williams classification
what are the classes in the vaughan williams classification?
class 1 - Na+ channel blockers class 2 - beta blockers class 3 - K+ channel blockers class 4 - Ca2+ channel blockers class 5 0 agents that work by other moa
what are the 3 types of Na+ channel blockers?
class 1 a - lengthens the action potential class 1b - shortens the action potential class 1c - no effect on action potential
what are examples of class 1a from vaughan williams classification?
dispyramide
quinidine
procainamide
what are examples of class 1b from vaughan williams classification?
lidocaine and phenytoin
what are examples of class 1c from vaughan williams classification?
flecanide and propafenone
what are examples of beta blockers?
atenolol and brisopolol
what are examples of K+ channel blockers?
amiodarone and sotalol
what are examples of Ca2+ channel blockers?
verapamil and diltiazem
what are examples fo class 5 agents on the vaughan williams classification?
adenosine
digoxin
magnesium
atropine
what is a DC sock?
direct current cardioversion defibrilation
what type of drug is digoxin?
a digitalis glycoside
what is digoxins moa?
inhibting Na+/K+ ATPase which increases intracellular Na+ which then drives the influx of Ca2+ into the heart causing increased contractility
what are side effects of digoxin
confusion dizzy nausea and vomiting diarrhoea vision changes skin rashes
what are contraindications for digoxin?
acute MI hypersensitivity ventricular fibrillation myocarditis hypomagnesemia hypokalaemia wolf-Parkinson-white syndrome
what is lidocaines moa?
blocks N+ channels so the heart is less likely to conduct early action potentials which may be causing arrythmias
what are side effects of lidocaine?
bluish lips/fingernails/palms double vision chest pain cold/clammy/pale tinnitus difficultu breathing and swallowing dizziness
what are side effects of beta blockers?
fatigue dizzy cold extremiirs difficulty sleeping and nightmares nausea
what are side effects of Ca2+ channel blocker?
cosntipation
worsening cardiac outpit
bradycardia
what is amiodarones moa?
blocks k+ channels which relaxes smooth muscle lining bascular walls = decreases afterload
what is atropines moa?
it competitively blocks effects of ACh at muscrinic cholinergic receptors on cardiac muscle
