Cardiovascular Drugs Flashcards
Therapeutic uses of Lidocaine for arrhythmias
Class 1 B tachyarrhythmia drug
IV for ventricular arrhythmias due to general anesthetics, surgery, ischemia and trauma
Digitalis induced arrhythmias
Examples of Benzodiazepines
Diltizem
Classifications of drugs used to treat Tachyarrhytmias
Class I (A, B, C)
Class II
Class III
Class IV
Drug of choice in cats for treatment of Myocardial Hypertrophy
Diltiazem
Drug recommended as the first line antihypertensive in cats unless the cause is hyperthyroidism.
Amlopdipine
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Beta Blocker used if caused by hyperthyroidism
Examples of Dihydropyridines
Amlodipine
Nifedipine
Mechanism of action of Carvedilol
Nonselective beta blocker and alpha1 blocker
Inhibits endothelin (ET) release
Drug of choice to treat atrial fibrillation in horses
Quinidine
Drugs used in the treatment of bradyarrythmias
Atropine
Isoproterenol
Epinephrine
Classifications of Calcium Channel Blockers
Diphenyl Alkylamines
Benzodizepines
Dihydropyridines
Examples of Diphenyl Alkylamines
Verapamil
Examples of Direct-Acting Vasodilators
Hydralazine
Nitrates
Mechanism of action of Calcium Channel Blockers
Inhibit the influx of extracellular calcium → decrease in intracellular calcium inhibits myocardial contraction → dilation of coronary and systemic arteries
Cardiac Stimulants
Beta-1 Agonists
Phosphodiesterase Inhibitors
Glucagon
Calcium Salts
Examples of Class III tachyarrhythmia drugs
Bretylium
Amiodarone
Sotalol
Other agents used in the treatment of CHF
Oxygen therapy
Morphine sulfate
Aminophylline
Nebulization of ethanol
Examples of Angiotension II Antagonists
Losartan
Effect of Class III tachyarrhythmia drugs
Prolong action potential duration by blocking potassium channels
Examples of Non Selective Alpha Blockers
Phentolamine
Phenoxybenzamine
Therapeutic uses of Phenytoin
Class 1 B tachyarrhythmia drug
Digitalis induced arrhythmias in dogs ONLY
Predisposing factors of tachyarrhythmias caused by digitalis glycoside use
Hypokalemia
Hypomagnesemia
Hypercalcemia
Hypernatremia
Hypothyroidism
Hyperthyroidism
Hyposemia
Mechanism of action of Angiotension II Antagonists
Competitive antagonist of angiotension II receptors
Examples of Indirect Sympatholytics
Bretylium
Sinus bradycardia can be treated with
Atropine
Isoproterenol
Types of arrhythmias
Tachyarrhythmia
Bradyarrhythmia
Drugs used to treat emergency hypertension or hypertensive crisis
Hydralazine or Sodium Nitroprusside IV
Propranolol or Acepromazine IV
Phentolamine IV
Oral Calcium Blockers - Prazosin or ACE Inhibitors
Effect of Class I C tachyarrhythmia drugs
No effect on action potential
Adverse effects of Pimobendan
Diarrhea
Vomiting
Inappetence
Seizures
PU/PD
Sympatholytic drug types
Non Selective Alpha-Blockers
Selective Alpha1 Blockers
Presynaptic Alpha2 Blockers
Nonselective Beta-Blockers
Selective Beta1 Blockers
Beta and Alpha Blockers
Indirect Sympatholytics
Effects of Digitalis Glycosides on the Kidney
Diuretic effect maily secondary to increased cardiac output
Example of Beta and Alpha 1 Blockers
Carvedilol
Diuretics used to treat hypertension
Hydrochorothiazide
Furosemide
Examples of Nitrates
Sodium Nitroprusside
Nitroglycerin
Isosorbide Dinitrate
Categories of drugs used to treat Congestive Heart Failure
Positive Inotropic Drugs
Inodilators
Vasodilators
Diuretics
Beta-Blockers
Pharmacokinetics of ACE Inhibitors
Oral Administration (Exception - Enalapril)
Food reduces absorption of captopril
Onset and duration of action variable
Activation in liver
Therapeutic use of Quinidine
Class 1 A tachyarrhythmia drug
Ventricular arrhythmias
Atrial fibrillation in horses, cattle and large breeds of dogs
Cardiovascular effects of Digitalis Glycosides
Positive inotropic effect
Reduction in sinus rate and slowing of AV conduction
Prolonged PR intervals in ECG
Increased mechanical efficiency of the failing heart
Normalization of blood pressure and peripheral resistance
Non-drug therapy for congestive heart failure
Restricted Salt Diet
Restricted Exercise
Examples of Selective Betal 1 Blockers
Atenolol
Examples of Nonselective Beta Blockers
Propranolol
Atrial Flutter can be treated with
Digoxin
Quinidine, Procainamide, Propranolol
Pharmacokinetics of Pimobendan
Oral administration
Metabolically activated in liver
Metabolites excreted in feces
Bound to plasma proteins
Types of Supraventricular Tachyarrhythmias
Atrial Tachycardia
Atrial Flutter
Atrial Fibrillation
ACE Inhibitor that is least likely to require dosage modification in renal failure patients because of significant excretion in bile
Benazepril
Treatment of tachyarrhythmias in cats
Beta-blockers are the drugs of choice for both supraventricular and ventricular tachyarrhythmias
Mechanism of action for Pimobendan
Acts by sensitixation of the cardiac contractile apparatus to calcium by enhancing interaction between calcium and troponin C complex → Increase intracellular calcium and increas myocardial oxygen consumption by inhibiting PDE II and V
Mechanism of action of ACE inhibitors
Inhibition of Angiotension Converting Enzyme → Inhibition of Angiotension II synthesis → Inhibition of Aldosterone → Increase in renin → Increased bradykinin
Examples of Beta-1 Agonists
Dopamine
Dobutamie
Examples of Beta-Blockers used to treat CHF
Carvedilol
Metoprolol
Atenolol
Ventricular Premature Complexes can be treated with
Quinidine, Procainamide, Lidocaine
Phenytoin
Propranolol
Ventricular Tachycardia can be treated with
Procainamide, Lidocaine
Quinidine, Phenytoin
Propranolol
ACE inhibitors that are long lasting, only need to be administered once daily
Benazepril
Lisinopril
Examples of Presynaptic Alpha2 Agonists
Clonidine
Examples of Class IV tachyarrhythmia drugs
Verapamil
Diltiazem
Cardiac Asystole/Cardiac Resuscitation can be treated with
Epinephrine
Examples of Inodilators
Pimboendan
Inamrinone
Milrinone
Adverse effects of Digitalis Glycosides
Narrow safety margin
Increased sensitivity in cats
Tachyarrhythmias
Bradyarrhythmias
GI signs
Alteration of serum potassium
Therapeutic uses of Propranolol
Class II tachyarrhythmia drug
Paroxysmal supraventricular tachycardia
Digitalis induced tachyarrhythmias
Arrhythmias due to inhalation anesthesia
Treatment of bradyarrhythmias caused by the use of digitalis glycosides
Drug withdrawal
Atropine
Effect of Digitalis Glycosides on the Gastrointestinal Tract
GI irritation
Vomiting
Categories of Diuretics used in treatment of CHF
Loop Diuretics
Thaizide Diuretics
Potassium Retaining Diuretics
Example of Loop Diuretic
Furosemide
Class III tachyarrhythmia drug that is a non-selective beta-blocker
Sotalol
Vasodilators used to treat hypertension
ACE Inhibitors
Angiotension II Antagonists
Hydralazine
Alpha Blockers
Examples of Class I B tachyarrhythmia drugs
Lidocaine
Phenytoin
Toxainide
Mexiletine
Aprinidine
Atrial Tachycardia can be treated with
Digoxin
Procainamide, Propranlol
Quinidine, Phenytoin
Therapeutic uses of ACE Inhibitors
Congestive Heart Failure
Hypertension
Chronic renal insufficiency - cats
Mechanism of action of Digoxin
Inhibits Na K ATPase → increases intracellular calcium resulting in positive inotropic effect
Contraindications of Pimobendan
Should not be used in hypertrophic cardiomyopathy
When increase of cardiac output is physically impossible
Effect of Class I B tachyarrhythmia drugs
Shortens action potential
Therapeutic uses of Verapamil and Diltiazem
Class IV tachyarrhythmia drug
Supraventricular tachyarrhythmias
Myocardial hypertrophy
Examples of Class I C tachyarrhythmia drugs
Flecainide
Encainide
Lorcainide
Examples of selective alpha 1 agonist
Phenylephrine
Mechanism of action of Hydralazine
Increase local concentrations of PGI2 → inhibits calcium influx into smooth muscle of arteries
Examples of Positive Inotropic Drugs
Digitalis glycosides
Beta-1 agonists
Example of Potassium Retaining Diuretic
Spironolactone
Triameterene
Amiloride
Atrial Fibrillation can be treated with
Digoxin
Propranolol
Quinidine, Procainamide
Mechanism of action of Nitrates on vasculature
Formation of reactive radial nitric oxide (NO) → Activation of Guanylyl cyclase → Increase in cyclic GMP → Stimulation of GMP-dependent protein kinase → Alteration of phosphorylation of proteins and dephosphorylation of myosine light chain → Relaxation of smooth muscle of blood vessels
Types of vasodilatory drugs
Sympatholytic Drugs
ACE inhibitors
Angiotension II Antagonists
Direct Acting Vasodilators
Calcium Channel Blockers
Examples of Class II tachyarrhythmia drugs
Propranolol
Timolol
Pindolol
Oxyprenolol
Alprenolol
Atenlol
Esmolol
Metoprolol
Treatment of tachyarrhythmias caused by use of digitalis glycosides
Drug withdrawal
Potassium IV
Anti-arrhythmic drugs
Cholestyramine
Digoxin Immune Fab
Examples of ACE inhibitors
Captopril
Enalapril
Lisinopril
Benazepril
Effect of Class I A tachyarrhythmia drugs
Prolong action potential
Clinical use of Angiotension II Antagonists
Antihypertensive
Mechanisms of arrhythmias
Abnormal automaticity
Abnormal conduction - reentry
Disturbances in both automaticity and impulse conduction
Types of ventricular tachyarrhythmias
Ventricular premature complexes
Ventricular tachycardia
Adverse Effects of ACE Inhibitors
Hypotension
Decrease intraglomerular pressure → Decrease GFR → Systemic hypertension and azotemia
Captopril - may cause idiosyncratic glomerular disease in dogs, and GI side effects
Trade name of Pimobendan
Vetmedin
Examples of Vasodilators
ACE Inhibitors
Hydralazine
Nitrates
Prazosin
Therapeutic use of Procainamide
Class 1 A tachyarrhythmia drug
Ventricular arrhythmias > Atrial arrhythmias
Examples of Nitrates that have an effect on vasculature
Sodium Nitroprusside
Nitroglycerin
Isosorbide Dinitrate
Common Digitalis glycosides
Digitoxin
Digoxin
Examples of Class I A tachyarrhthymic drugs
Quinidine
Procainamide
Disopyramide
Arrhythmia
Abnormality in heart rate and rhythm - any rhythm that is not normal sinus rhythm
Examples of causes of arrhythmia
Imbalance of SNS and PSNS
Change in serum potassium, calcium or magnesium
Hypoxemia
Acidosis
Mechanical trauma
Myocardial disease
Cardiac ischemia
Myocardial infaction
Drugs
Treatment of GI adverse effects caused by digitalis glycosides
Drug withdrawal
Fluid Therapy
Examples of Selective Alpha 1 Blockers
Prazosin
Terazosin
Doxazosin
Effects of Calcium Channel Blockers on the heart
Negative inotropic effect
Negative chronotropic effect
Increase oxygen delivery to the myocardial tissue
Decrease afterload
Coronary vasodilation
Pharmacokinetics of Digitalis Glycosides
Oral administration or slow IV in emergency
Elixir bioavailability > tablet
Metabolized by liver
Undergoes enteroheptaic recycling
Excretion renal (dogs/horses) or renal and hepatic (cats)
Classifications of antihypertensive drugs
Diuretics
Beta-Blockers
Vasodilators
Beta-Blockers used to treat hypertension
Propranolol
Atenolol
Therapeutic uses of Pimobendan
Congestive Heart Failure - dogs
Adjunctive therapy for Dilated Cardiomyopathy (DCM) and Chronic Degenerative Valvular Disease (CVD)
Examples of Beta-1 Agonists
Isoproterenol
Epinephrine
Norepinephrine
Dopamine
Examples of ACE Inhibitors
Captopril
Enalapril
Benazepril
Lisinopril
Examples of nonselective alpha agonists
Epinephrine
Norepinephrine
Classification of Pimobendan
Positive inotrope and balanced vasodilator
Therapeutic uses of Bretylium
Class III tachyarrhythmia drug
Refractory and recurrent tachyarrythmias
Example of Thiazide Diuretic
Hydrochlorothiazide
Chlorothiazide
Types of vasoconsticting drugs
Nonselective Alpha Agonists
Selective Alpha 1 Agonists
Direct and Indirect Sympathomimetics
Example of Direct and Indirect Sympathomimetics
Ephedrine
Pseudoephedrine
Phenylpropanolamine (PPA)
Effect of Class II tachyarrhythmia drugs
Beta-blockers
Therapeutic uses of Digitalis Glycosides
Congestive Heart Failure
Atrial Arrhythmias
Adverse effects of Calcium Channel Blockers
Bradycardia and AV block
Hypotension
GI side effects
Elevated liver enzymes
Drug of choice to treat Phenochromocytoma- Induced Hypertension
Phenoxybenzamine
Mechanism of action of Class IV tachyarrhythmia drugs
Calcium channel blockers
Types of bradyarrhythmias
Sinus bradycardia
Second-degrre AV block
Cardiac asystole- cardiac resuscitation
Effects of Calcium Channel Blockers on blood vessels
Decrease peripheral resistance
Decrease systemic blood pressue
Therapeutic uses of Calcium Channel Blockers
Antiarrhythmic (Class IV)
Antihypertensive
Myocardial Hypertrophy
Antianginal - Ischemic Heart Disease
Adverse gastrointestinal effects seen with use of digitalis glycosides
Anorexia
Vomiting
Diarrhea
Mechanism of action of Class I Tachyarrhythmic drugs
Sodium channel blockers
Example of Phosphodiesterase Inhibitor
Aminophylline
Second-Degree AV Blocks can be treated with
Atropine
Isoproterenol
Glucagon