Cardiovascular drugs Flashcards
Anti-arrhythmic drugs
Sodium Influx Inhibitors (CLASS 1) Beta Blockers (CLASS 2) Potassium channel blockers (CLASS 3) Calcium channel blockers (CLASS 4)
Arrhythmia definition
any abnormal pattern of electrical activity in the heart
Sodium influx inhibitors - action
Reduces influx of sodium into the myocardium which slows the heart rate and allows sinus rhythm to return to normal
Sodium influx inhibitors - Examples
- Lidocaine/ligoncaine
- Quinidine
- Procainamide
- Mexiletine
Sodium influx inhibitors - side effects
If conduction is slowed too much, depolarisation can stop at the AV node, preventing conduction to the ventricles. – Atrioventricular block
This can be detected on and ECG as an ossasional Pwave which is not followed by the QRD complex.
Cats are sensitive to lignocaine - can develop bradycardia and sizures
Sodium influx inhibitors - Clinical uses
Treats tachyarrhythmias
Beta blockers - action
(MAKE YOU FEEL BETA)
Blocks the sympathetic nervous system, slows everything down to help prevent arrhythmias.
Can be used in humans to reduce heart palpitations related to anxiety.
Beta blockers - examples
- PropanLOL
- CarvediLOL
- MetoproLOL
- AtenoLOL
- EsmoLOL
Beta blockers - clinical uses
Hypertension Cardiac dysrhythmias Hypertrophic obstructive cardiomyopathies Hyperthyroidism Glaucoma Heart Failure
Beta blockers - side effects
- Bradycardia
- Heart failure
- syncope (fainting)
- Bronchoconstriction
- Diarrheoa
- Peripheral vasoconstriction
- Weaken force of cardiac contraction
Beta blockers - side effects
- Bradycardia
- Heart failure
- syncope (fainting)
- Bronchoconstriction
- Diarrheoa
- Peripheral vasoconstriction
- Weaken force of cardiac contraction
Calcium Channel Blockers - action
Drugs work by slowing the movement of calcium into cardiac muscle cells.
decreasing conduction and slowing the hear allowing normal rhythms to be restored
Calcium Channel Blockers - examples
Verapamil
Diltazem (hypercard)
Amlodipine - hypertension in cats
Calcium Channel Blockers - side effects
Decreased force of cardiac contractions (negative inotropic effects)
Hypotension and bradycardia
AVOID IN CASES OF CONGESTIVE HEART FAILURE
GI Upset
Calcium Channel Blockers - clinical uses
supraventricular tachycardia
heart failure
hypertrophic cardiomyopathy
circulatory shock and trauma
Positive inotropes
drugs that increase the strength of contractions made by the heart.
Thickened or weak myocardium walls are unable to contract adequately
Vasodilators
Drugs that cause the blood vessels to dilate
Leeds to an increased volume of blood being pumped around the body
Diuretics
Drugs which increase diuresis.
Reduces blood volume by removing water
can be useful when there is an excess amount of fluid in cardiovascular system
Positive inotropes - action
Increase the strength of cardiac contraction
Positive Inotropes
- What are catecholamines?
Catecholamines are chemicals produced by the body which stimulate the sympathetic nervous system
Positive Inotropes
- Catecholamines, examples - natural
-Norepinphrine
Epinephrine
Dopamine
Positive Inotropes
- Catecholamines, examples - synthetic
Dobuatmine
Increases contractility
Used to treat septicf and cardiogenic shock
