Pharma 7

Question 1

State the effect of a positive Inotrope:

Answer 1

Improves cardiac contractility.

Question 2

What is effect of a vasodilator?

Answer 2

Decreased peripheral vascular resistance.

Question 3

What is meant by the term preload?

Answer 3

The pressure that is exerted on a ventricle (ie. the pressure that stretches the ventricle)

Question 4

What is meant by the term after-load?

Answer 4

The pressure the heart chamber must produce to overcome arterial pressure, open the valve and eject blood into the artery.

Question 5

What is the effect of parasympathetic nervous system control on the heart?

Answer 5

Bradycardia and a slight decrease in myocardial contractility.

Question 6

What is the effect of the sympathetic nervous system on the heart?

Answer 6

Tachycardia and increased myocardial contractility.

Question 7

Briefly explain how RAAS compensation can become a problem:

Answer 7

Decreased renal blood flow causing increased renin release causing increased angiotensin 2 causing increased preload and increased afterload.

Question 8

What drug class should be used to improve contractility of the heart?

Answer 8

positive ionotropes

Question 9

What drugs should be used to decrease the amount of peripheral resistance?

Answer 9

vasodilators

Question 10

What drugs should be used to remove fluid accumulation?

Answer 10

Diuretics

Question 11

What type of drug should be used to restore the normal heart rate and rhythm?

Answer 11

Antiarrthymics

Question 12

Name the drug that is referred to as an “inodilator” and briefly explain how it works:

Answer 12

Pimobendan. Acts a positive inotrope and a mild vasodilator. It increases the sensitivity of the contractile proteins (troponin C) to existing levels of intracellular calcium.

Question 13

What is the primary effect of dobutamine and why is it given IV?

Answer 13

Acts via a B1 effect of improve myocardial contraction force to improve cardiac output. It is very short acting and hence it is often given as an infusion. (has very minimal effect on the heart rate)

Question 14

When are the vasodilators normally used clinically?

Answer 14

Cases of heart failure and hypertension.

Question 15

How do the ACE inhibitors work?

Answer 15

They inhibit the angiotensin converting enzyme (ACE) . This then prevents the increased blood pressure from occurring by preventing conversion of angiotensin 1 to angiotensin 2

Question 16

What is the suffix that is typically found on the end of the ACE inhibitor drugs?

Answer 16

-pril is normally found on the end of them

Question 17

What is the effect of the beta (B) blockers and what are some examples of them?

Answer 17

B1 antagonism leads to decreased heart rate and negative inotropy. An example of this is propranolol and atenolol.

Question 18

What are the effects of the calcium channel blockers?

Answer 18

1. Decreased myocardial contractility
2. Vasodilation
3. Slows atrioventricular (AV) pulse conduction

Question 19

What is an example of calcium channel blockers?

Answer 19

Amlodipine (also the gold standard for cats)

Question 20

What is the effect of the nitrates and how do they exert their effects?

Answer 20

Nitrate caused nitric oxide formation which then produces vasodilators that reduce preload (they do experience a significant pass effect).

Question 21

Provide an example of a topical preparation of the nitrates and an injectable preparation.

Answer 21

Nitroglycerin = a topical preparation 
Nitroprusside = an injectable