Heart Failure and Angina Flashcards Preview

AU 15 - Pharmacology Exam 3 > Heart Failure and Angina > Flashcards

Flashcards in Heart Failure and Angina Deck (36):
1

What is heart failure?

Condition in which the heart can't pump enough blood to meet the body's needs
Sometimes because the heart doesn't fill with enough blood, sometimes because the heart can't pump with enough force, sometimes both

2

What are the two types of heart failures? How often does each occur?

Systolic (50%)
Diastolic (50%)

3

Systolic Heart failure

Weakened heart muscle can't squeeze as well
Can't get blood through the body
Ventricles are enlarged and pump out less than 40-50% of blood (normally pumps 60%)

4

Diastolic heart failure

Stiff heart muscle can't relax normally
Stiff ventricles fill with less blood than normal
Ventricles pump out about 60% of the blood, but the amount of blood is lower

5

What are the classifications of Heart failure?

Class I (mild)
Class II (mild)
Class III (moderate)
Class IV (severe)

6

Excitation-Contraction coupling

Contraction is the result of Ca influx from depolarization causing the release of more Ca from the SR
Liberated Ca binds to troponin leading to a change in the interaction between actin and tropomyosin, exposing myosin
Myosin pulls on the actin as it hydrolyzes ATP, contracting the muscle

7

Depolarization of the cardiac myocyte leads to what?

Opening of the voltage-gated Ca++ channels

8

Ryanodine receptor

This is the receptor on the membrane of the SR, and when Ca binds to it, it releases more Ca into the cell

9

What factors contribute to how well the heart pumps blood?

1) Sensitivity of contractile proteins to Ca
2) Amount of Ca that is released
3) Amount of Ca stored in the SR
4) Amount of Ca that enters the cell upon depolarization
5) Activity of the Na/Ca exchanger
6) Intracellular Na concentration and activity of the Na/K ATPase

10

Ionotropic drugs

Alter the force or energy of muscular contractions
There are both positive and negative ionotropic drugs

11

Negative ionotropes

Weaken the force of muscular contractions

12

Positive ionotropes

Increase the strength of muscular contractions

13

Chronotropic drugs

May change the heart rate by affecting the nerves controlling the heart, or by changing the rhythm produced by the SA node

14

Positive chronotropes

Increase the heart rate

15

Negative chronotropes

Decrease the heart rate

16

What are the different types of ionotropes used to treat heart failure?

Cardiac glycosides
B-adrenergic receptor agonists
Bipyridines

17

Cardiac glycosides

Digoxin is the only one used in the US
Blocks Na/K ATPase pump
-internal Na increases
-slows the Na/Ca exchanger, slowing the removal of Ca

18

What are the theraputic effects of cardiac glycosides/digoxin?

Increase the contractility
-increase ventricular ejection and decrease end diastolic and systolic cardiac size
-Increase CO and increase renal perfusion
-The above effects lead to a decrease in sympathetic and renal responses

19

What drugs without positive ionotropic effects can be used to treat heart failure?

B-adrenergic receptor antagonists
Diuretics
ACE inhibitors and angiotensin receptor antagonists
Aldosterone receptor antagonists
Direct vasodilators

20

What are the suggested mechanisms of B-adrenergic antagonists used to treat heart failure?

Attenuation of adverse effects of catacholamines
Up-regulation of B-receptors (possibly through decreased desensitization)
Decreased HR
Decreased catacholamine-mediated remodeling

21

Most patients (91%) of patients with heart disease also have what?

Periodontitis

22

Angina

Pain or discomfort in the chest that happens when some part of the heart does not receive enough oxygen from the blood

23

What are the different types of angina?

Classical/Typical/Stable/Exertional Angina
Prinzmetal/Variant Angina
Unstable Angina

24

Classical/Typical/Stable/Exertional Angina

Due to fixed and stable plaque

25

Prinzmetal/Variant Angina

Due to spasm of the coronary artery

26

Unstable Angina

Due to unstable plaque

27

What drugs can be used to treat Anginas?

Nitrates/Nitrites
B-adrenergic receptor blockers
Calcium channel bloackers
Aspirin, antiplatelet, and anticoagulant drugs
Ranolazine

28

Nitrates and nitrites used to treat angina are what?

Esters of nitrous or nitric acid

29

All of the organic nitrates/nitrites used to treat angina are prodrugs that spontaneously produce what?

Nitric oxide - produce vasodilation

30

Nitroglycerin

Apply under the tongue for acute episodes of angina; can also be absorbed in GI tract or skin
Therapeutic effect is apparent within 1-3 minutes of sublingual tablets, 30-60 minutes of applying ointment or patch, and 1-2 minutes via IV

31

Longer acting nitrates are effective when?

Effective when taken orally

32

What are adverse effect(s) of nitroglycerin and other nitrates?

Headache

33

High doses of organic nitrates can cause what?

Postural hypotension
Facial flushing
Tachycardia

34

What effect can viagra have when taken with nitrates?

Potentiates the action of nitrates - leading to dangerous hypotension

35

How do B-blockers help treat angina?

Decrease HR and O2 demand in the SA node
Decrease contractility and O2 demand in the ventricle myocardium
Decrease BP and O2 demand in arterioles

36

How do Ca-channel blockers help treat angina?

Decrease HR and O2 demand in the SA node
Decrease contractility and O2 demand in the ventricular myocardium
Increase vasodilation and O2 supply in the coronary arteries
Decrease BP and O2 demand in the arterioles