Mod 6- Antiarrythmic Agents Flashcards
What electrolytes can alter action potentials of the heart?
sodium, potassium, calcium and magnesium
What is the action of Class 1 Antiarrhythmics?
Blocks the sodium channels in the cell membrane during an action potential
What is the action of Class II Antiarrhythmics?
Blocks beta-receptors (beta adrenergic), causing depression of phase 4 of the action potential
What is the action of Class III Antiarrhythmics?
Prolongs Phase 3
What is the action of Class IV Antiarrhythmics?
Blocks calcium channels; works on phase 2
Ia Antiarrhythmic Drugs
Disopyramide
Procainamide
Quinidine
Ib Antiarrhythmic Drugs
lidocaine
mexiletine
Ic Antiarrhythmic Drugs
Flecainide
propafenone
What phase do Class I Antiarrhythmics impact?
Phase 0
Indications for a Class I Antiarrhythmic
management of acute ventricular arrhythmias during cardiac surgery or MI
Contraindications for Class I Antiarrhythmics
Allergy bradycardia or heart block CHF hypotension or shock electrolyte disturbances
Cautions for Class I Antiarrhythmics
Renal/ hepatic dysfunction
pregnancy
ADE of Class I Antiarrhythmics
*CNS: dizziness, fatigue, slurred speech
GI- N/V
*CV- arrhythmia
respiratory depression
Misc.- rash, loss of hair, bone marrow suppression
Drug/ Drug interactions for Class I Antiarrhythmics
quinidine & digoxin- inc. digoxin toxicity
oral coagulants- inc. bleeding
digoxin & beta blockers- inc. risk for arrhythmias
Drug/ Food interactions of Class I Antiarrhythmics
Foods that alkalinize the urine- citrus, vegetables, antacids, milk products
Grapefruit juice
Antiarrhythmic Prototype
Lidocaine
Class I pneumonic: Double Quarter Pounder
Lettuce, Mayo, Tomato
More Fries Please
Disophyramide, Quinidine, Procainamide
Lidocaine, Mexiletine, Tocainide
Moricizine, Flecainide, Propefanone
What is the suffix of Class II Antiarrhythmics?
“-olol”
acebutolol
esmolol
propanolol
What is the action of Class II Antiarrhythmics?
Slows down the HR
When are Class II Antiarrhythmics indicated?
used for super ventricular tachycardia >150bpm
Contraindications for Class II Antiarrhythmics?
Sinus bradycardia, AV block, cardiogenic shock, CHF, asthma (can cause bronchospasm), respiratory depression, pregnancy, lactation
Caution for Class II Antiarrhythmics
diabetics- can mask signs of hypoglycemia
thyroid dysfunction- can mask signs
renal/ hepatic dysfunction
ADE of Class II Antiarrhythmics
Blocking the SNS
*CNS- diziness, insomnia, dreams, fatigue
*CV- hypotension, bradycardia, AV block, arrhythmias
Respiratory- bronchospasm, dyspnea
GI- N/V, anorexia
Misc.- loss of libido, dec. exercise tolerance, alterations in blood glucose levels
Drug/ drug interactions of Class II Antiarrhythmics
Verapamil- increased drug effects
Insulin- risk of hypoglycemia
Class II Antiarrhythmic Prototype
Propranolol
Action of Class III Antiarrhythmics
Blocks the potassium channels and slows outward movement of potassium- prolongs action potentials
Class III Antiarrhythmic Medications
Amiodarone
Dofetilide
Sotalol (-alol belong to potassium channel blockers)
Indications for Class III Antiarrhythmics
Life threatening ventricular arrhythmias
maintenance of sinus rhythm after conversion of atrial arrhythmias
Contraindications for Class III Antiarrhythmics
None bc situation is life threatening
Caution for Class III Antiarrhythmics
Shock, hypotension, respiratory depression, prolonged QT interval, renal/ hepatic disease
ADE of Class III Antiarrhythmics
N/V, weakness, dizziness, arrhythmias
Drug/ Drug interactions of Class III Antiarrhythmics
Digoxin or quinidine- increase of serious toxicity
Consult a drug guide unless given during emergency
What specific toxicity can happen with the first dose of Class III Antiarrhythmic Amiodarone?
pulmonary toxicity and vision changes happen when on it long term
Class III Antiarrhythmic Prototype
Amiodarone
Class III Antiarrhythmics- SAD Banana
Potassium channel blockers-
Sotalol
Amiodarone
Dofelitide
Class IV Antiarrhythmic Medications
Diltiazem
Verapamil
Class IV Antiarrhythmic actions
block movement of calcium; slow conduction through the AV node
Indications for Class IV Antiarrhythmics
supraventricular tachycardia (SVT) control the ventricular response to rapid atrial rates
Contraindications for Class IV Antiarrhythmics
allergy, sick sinus syndrome or heart block, pregnancy, lactation, CHF, hypotension
Cautions for Class IV Antiarrhythmic
idiopathic hypertrophic subaortic stenosis
renal/ liver impairment
ADE of Class IV Antiarrhythmics
CNS- weak, dizzy on standing, hypotension
Drug/ Drug interactions of Class IV Antiarrhythmics
MANY consult drug guide
Class IV Antiarrhythmic Prototype
Diltiazem
Class IV Antiarrhythmic
Very Dairy
r/t calcium
Verapamil
Diltiazem
McDonald’s Salt Shaker is the mnemonic for which antiarrhythmic?
Class I- sodium channel blockers
How is adenosine used to treat arrhythmias?
basically stops all electrical activity in the heart, very painful
How is digoxin used to treat arrhythmias?
Negative chronotrope that slows the HR
slows calcium from leaving the cells
How is dronedarone used to treat arrhythmias?
used to reduce risk of hospitalization in pts w/ persistent AF or flutter who have risk factors for CVD and scheduled to be converted to sinus rhythm
What blood tests do we monitor for antiarrhythmic agents?
CBC, Liver & kidney function
What needs to be continually monitored while on an antiarrhythmic?
Cardiac rhythm
Is it better to administer antiarrhytmics paternally or orally
Oral if feasible