Deck 5: Drugs Affecting the Cardiovascular System

Question 1

Muscular contraction involves a stepwise series of events. In order for a subsequent contraction to take place, the original polarized state of the myocytes must be restored. For the period of time that it takes to repolarize, the myocyte is unable to contract. This period of time is called the

A)rest period.
B)setting period.
C)refractory period.
D)relative period.

Answer 1

refractory period.

Question 2

The parasympathetic (PSNS) and sympathetic (SNS) nervous systems function to counter balance one another. As one system upregulates, the other is diminished. What would you expect to occur to the autonomic nervous system if you administer a drug such as glycopyrrolate, which is considered an anticholinergic?

A)Downregulation of the PSNS, Upregulation of the SNS
B)Downregulation of the SNS, Upregulation of the PSNS
C)Downregulation of both arms of the autonomic nervous system
D)Upregulation of both arms of the autonomic nervous system

Answer 2

Downregulation of the PSNS, Upregulation of the SNS

Question 3

What is the function of the ACE inhibitors?

A)Block release of renin from the kidney
B)Interfere with the conversion of angiotensinogen to angiotensin I
C)Interfere with the conversion of angiotensin I to angiotensin II
D)Directly inhibit the release of aldosterone from the adrenal gland

Answer 3

Interfere with the conversion of angiotensin I to angiotensin II

Question 4

The specialized cells of the heart that are not responsible for muscle contraction but instead are responsible for the heart's electrical conduction system include all but

A)SA node.
B)Purkinjie fibers.
C)AV node.
D)depolarizing cells.

Question 5

Of the four adrenergic receptors which is located primarily in the heart

A)( $\alpha$ ₁.)
B)( $\alpha$ ₂.)
C)( $\beta$ ₁.)
D)( $\beta$ ₂.)

Question 6

The class 1 sodium channel blocker is used as an antiarrhythmic, which works by decreasing the rate of Na⁺ movement into a cell through the sodium fast channel most commonly used is

A)digoxin.
B)epinephrine.
C)lidocaine.
D)quinalone.

Question 7

Which of the following does not occur with stimulation of the sympathetic nervous system?

A)Increased bronchiole dilation
B)Stimulation of cardiac output
C)Coronary vasodilation
D)Peripheral arteriolar vasodilation

Question 8

Adrenergic effects on the heart are to

A)increase heart rate.
B)decrease heart rate.
C)decrease contraction strength.
D)increase blood pressure.

Question 9

Depolarization and repolarization of cardiac cells primarily involve movement of _____ and _____.

A)Ca⁺, P⁺
B)Ca⁺, Na⁺
C)Na⁺, K⁺
D)K⁺, Ca⁺

Question 10

Lidocaine is used to treat certain specific cardiac arrhythmias. Of the following, choose the statement about lidocaine that is correct.

A)Lidocaine functions in the heart as a local anesthetic to decrease chest pain
B)Lidocaine blocks potassium (K⁺) influx into myocytes
C)Lidocaine functions best as a ventricular antiarrhythmic
D)Lidocaine is effectively dosed orally for long term maintenance of cardiac disease

Question 11

With which of the following conditions would the use of diuretics be contraindicated?

A)Decreasing pulmonary edema
B)Treating intracranial pressure caused by head trauma
C)Easing the workload of a damaged heart
D)Treating a patient with electrolyte deficiencies

Question 12

Drugs that mimic the effects of epinephrine are called_______________.

A)adrenergic agonists
B)adrenergic antagonists
C)sympathomimeitcs
D)A and C

Question 13

__________________historically has been the most commonly used long term positive inotropic drug.

A)Digoxin
B)Epinephrine
C)Lidocaine
D)Quinalone

Question 14

A dog has been treated with the $\beta$ -blocking drug atenolol for the past 6 months. The dog's owners go on a 1 week vacation with their pet, but they forgot to pack the medication. While out one morning, a bee stings the dog on the neck and his breathing becomes labored. Why would using epinephrine (EpiPen) to address anaphylaxis be potentially dangerous in this scenario?

A)Epinephrine causes vasoconstriction
B)Adrenergic receptors are increased
C)Bee venom and epinephrine aren't compatible
D)Epinephrine isn't required if only breathing is affected

Question 15

________________blocks $\beta$ ₁-receptors on the SA node and AV node and slows the conduction if the depolarization wave.

A)Digoxin
B)Propranolol
C)Lidocaine
D)Quinalone

Question 16

Pressure receptors located in the major arteries that detect changes in blood pressure are called

A)pressure receptors.
B)bundle of His.
C)baroreceptors.
D)Purkinjie fibers.

Question 17

What is the neurotransmitter of the parasympathetic nervous system?

A)Serotonin
B)Epinephrine
C)Acetylcholine
D)Dopamine

Question 18

What is the name of the sole member of the inodilator class of medications that are used in veterinary medicine?

A)Digoxin
B)Hydralazine
C)Nitroglycerin
D)Pimobendan

Question 19

Why aren't positive inotropes such as the catecholamines used for long-term maintenance of cardiac muscle contraction dysfunctions?

A)Adrenergic receptor numbers decrease over time
B)Epinephrine is toxic at all doses
C)Catecholamines do not cause an increase in heart rate
D)These drugs aren't readily available

Question 20

Positive inotropic drugs

A)increase the heart rate.
B)increase the force of cardiac contractions.
C)cause bradycardia.
D)cause vasoconstriction.

Question 21

The class of this commonly used diuretic is named for the area of the nephron where it works, and causes diuresis by blocking the resorption of electrolytes, especially potassium.

A)Furosemide
B)Spironolactone
C)Mannitol
D)Hydrochlorothiazide

Question 22

The use of a mixed vasodilator results in a decrease of both arterial and venous resistance by dilating both types of vessels. With used of this medication, the heart's function improves because of the resulting decrease in __________ and ___________.

A)postload, myocyte activity.
B)vessel diameter, heart rate.
C)strength of contraction, heart rate.
D)preload, afterload.

Question 23

Calcium channel blockers such as Verapamil are effective therapies for which types of cardiac arrhythmias?

A)Bradyarrhythmias
B)Atrial arrhythmias
C)Ventricular tachyarrhythmias
D)Premature ventricular contractions

Question 24

What is the role of mannitol as a diuretic?

A)Electrolyte resorption blocker
B)Participates directly in osmotic diuresis in the tubules
C)Inhibits enzymes involved in cellular fluid dynamics
D)Dilates the vessels of the glomerulus

Question 25

A cat owner is startled to find his 7-year-old DSH acutely lame on her rear limbs. After quickly searching several cat web sites for help, he becomes convinced that the loss in limb function is because of a blood clot ("saddle thrombus"). Taking the advice of an online blog acquaintance instead of consulting with a veterinarian, the owner treats the cat with high doses of buffered aspirin. Why is this poor choice to treat this pet?

A)Cats biotransform aspirin to quickly to be effective
B)Aspirin would break the thrombus into many microthrombi
C)Aspirin wouldn't degrade the thrombus effectively
D)The buffering on this type of aspirin decreases its ability as an anticoagulant