Cardiac drugs Flashcards
Stimulation of alpha-1 receptors cause what to happen in the heart?
Vasoconstriction
Stimulation of beta-1 receptors cause what to happen in the heart?
Vasodilation
What is cardiac output?
The volume of blood being pumped by the heart.
The SA node is also called what?
The hearts pacemaker
The atrial depolarization is detected as what wave on the ECG?
P wave
The AV node does what within the heart?
Delays depolarization to ventricles.
How does the AV node display on the ECG?
flat area between P wave to QRS complex.
Depolarization of ventricles (contraction) displays how on the ECG?
QRS complex
Repolarization of ventricles displays how on the ECG?
T wave
What nervous system controls activity of the heart?
Autonomic
What are four compensatory mechanisms of the heart?
Increase HR
Increase stroke volume (volume pushing through)
Increase Heart muscle efficiency
Physiologic heart enlargement
What is congestive heart failure
When pumping ability of heart is impaired and sodium and water are retained in an effort to compensate for inadequate cardiac output.
What is an Arrhythmia
Any abnormal patterns of electrical activity in the heart.
Examples of Arrhythmias
PVC (premature ventricular contraction)—depolarization of ventricles out of the normal sequence
Ventricular Flutter—a series of PVC’s
Ventricular Fibrillation—prolonged or constant uncoordinated ventricular contractions leading to death
What are the two groups of Arrhythmias?
Bradycardia and Tacycardia
Are arrhythmias classified by location?
Yes
Atrial fibrillation is also known as what?
Supraventricular tachycardia
Causes of arrhythmias
Hypoxia
Electrolyte imbalances
Increased level or sensitivity to catecholamiens
Drugs
Trauma or disease affecting cardiac cells
Objectives in treatment of Cardiovascular disease
Control rhythm disturbances
Maintain or increase cardiac output
Relieve fluid accumulations
What are the three types of anti-arrhythmic drugs
Sodium influx inhibitors (Lidocaine) Beta Blockers (Atenolol) Calcium Channel Blockers (Cardizem)
What is a positive inotropic effect?
Increase the strength (force) of contractions.
What is a negative chronotropic effect?
Slow the heart rate
Is Angiotensin a potent vasoconstrictor?
Yes - inhibiting Angiotensin Converting Enzyme (ACE) results in vasodilation
What type of ant-arrhythmic drug is lidocaine?
Sodium influx inhibitor
What type of anti-arrhythmic drug is Propranool?
Beta Blocker
What will beta blockers do to the heart?
slow the heart rate
What type of ant-arrhythmic drug is Amlodipine (Norvasc)?
Calcium Channel Blocker
Atropine reverses what levels of AV block
1st or 2nd
Loops diuretics such as furosemide cause what
May cause hypokalemia with chronic use
A chronotropic agent affects what of the heart?
Rate of a contraction
What type of drug would be used to treat a cat with an aortic thromboemboism?
Fibrinolytic drug
What drug is used most commonly in patients with congestive heart failure?
Furosemide
What is digoxin?
A negative chronotrope and a positive inotrope
What is the drug of choice for the treatment of cardiac arrest in a surgical patient?
Epinephrine
What drug is used to treat feline hypertension?
Amolodipine (Norvasc)
ACE inhibitors have what effect on the body?
Decreased preload and afterload on the heart.
Nitroclycerin is given primarily to achieve what effect?
Vasodilation
What is Diltiazem used for?
Relax the heart of patients with HCM
Lidocaine is used to control what abnormalitiy
Ventricular tachyarrhythmia
What drug is classified as an osmotic diuretic used to reduce intracranial pressure or treat oliguric renal failure?
Mannitol
Hyperthyroid cats have heart rates over 200 bpm. What drug would be used to slow the heart rate?
Propranotol (It is a Beta 1 receptor blocker)
Drug classified as ACE inhibitors have what effect on the body?
Vasodilation
Captopril is an example of a
Vasodilator
