Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CVS > L05: Drugs And The Heart > Flashcards

L05: Drugs And The Heart Flashcards

1
Q

How can drugs act to affect the heart function

A

Directly

Indirectly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the direct action of drugs affect

A

Rate

Force of contraction in myocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does indirect action of drugs do to affect the heart function

A

Affect the vasculature

Affect blood volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why do we need drugs that affect the rate of the heart

A

To treat arrhythmia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is arrhythmia

A

A disorder where the area is disturbed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why is the rate disturbed in arrhythmia

A

Generation and conduction being abnormal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do anti arrhythmic drugs affect

A

The ion current which affect the AP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many classes of drugs does anti arrhythmic drugs have

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the classes of anti arrhythmic drugs dependent on

A

Which channels they work on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which channels does class 1 anti arrhythmic drugs work on

A

Voltage gated sodium channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are class 1 anti arrhythmic drugs

A

Voltage gated sodium channel blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Give an example of a class 1 anti arrhythmic drug

A

Lidocaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the role of class 2 anti arrhythmic drugs by blocking voltage gated sodium channels

A

Slows depolarisation and increases the refractory period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What channels do class 2 anti arrhythmic drugs work on

A

Beta 1 adrenoceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are class 2 anti arrhythmic drugs

A

Beta blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the role of class 2 anti arrhythmic drugs

A

Reduce the effect of the sympathetic ns on the SAN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give an example of a class 2 anti arrhythmic drug

A

Metropol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which channels do class 3 anti arrhythmic drugs work on

A

Potassium channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are class 2 anti arrhythmic drugs

A

Potassium channel blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the effect of the class 2 anti arrhythmic drugs

A

Prolong action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Give an example of a class 3 anti arrhythmic drug

A

Amiodarone

Solalol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which channels do class 4 anti arrhythmic drugs work on

A

L type (voltage gated calcium channels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are class 4 anti arrhythmic drugs

A

Voltage gated calcium channel blockers

24
Q

What is the effect of class 4 anti arrhythmic drugs

A

Reduce depolarisation in SAN and AVN

25
Q

What are non classified drugs

A

Drugs that do not get into classifications

26
Q

Name 2 non classified drugs involved in the heart

A

Adenosine

Cardiac glycosides

27
Q

Name an example of cardiac glycosides

A

Digoxin

28
Q

Which receptors do adenosine binds to

A

Adenosine receptors

29
Q

Where are adenosine receptros found

A

In the cells of SAN and AVN

30
Q

What happens when adenosine binds to adenosine receptors

A

It opens potassium channels

31
Q

What does opening of potassium channels cause

A

Hyperpolarisaton

32
Q

What does hyper-polarisation mean in terms of refractory period

A

Increases the refractory period and the cell become further away from reaching threshold after hyperpolarisation

33
Q

What is the role of cardiac glycosides

A

Increases vagal activity

34
Q

What does increase in vagal activity do

A

Decrease AVN conduction rate due to activation of the parasympathetic NS

35
Q

Why do we need drugs that affect force of contraction

A

To treat
Anaphylaxis
Heart failure

36
Q

What happens to cardiac output in cardiac failure

A

Insufficient for metabolic needs of the body

37
Q

How do we get cardiac myocytes contraction

A

Voltage gated calcium channels open due to depolarisation
This causes calcium influx
Calcium influx causes the release of other calcium from the sarcoplasmic reticulum
Calcium release moves regulatory complex from the actin binding site so myosin head binds to actin binding site to form a cross bridge and contraction

38
Q

If drugs want to affect the force of contraction what do they need to effect

A

The intracellular calcium levels

39
Q

Which drugs increase the intracellular calcium

A

Positive ionotrophic

40
Q

What are the 3 inotrophic drugs

A

Sympothomimetics
Cardiac glycosides
Phosphodiesterase inhibitors

41
Q

Give an example of cardiac glycosides

A

Digoxin

42
Q

What is the mechanism of action of cardiac glycosides

A

Partial inhibition of sodium/potassium ATPase

43
Q

How does the partial inhibition of sodium/potassium ATPase lead to the increase in intracellular calcium

A

1) after contraction some calcium will become stored back in the sarcoplasmic reticulum and some will be exchanged by sodium
2) calcium will leave out by a calcium/sodium transporter
3) another channel of sodium/potassium ATPase maintains the sodium concentration
4) dioxin partially acts on the sodium/potassium ATPase which causes a rise in sodium inside the cell
5) this makes the calcium/sodium exchanger less efficiency as there is lots of sodium in side the cell
6) this causes a rise in intracellular calcium

44
Q

What are the side effects of cardiac glycosides

A
  • Ionic disturbance which can cause excitability and therefore arrhythmia’s
  • gynaecomastia- breast growth in both sexes
45
Q

What are the other issues with using digoxin

A

Digoxin can interact with other drugs such as diuretics

46
Q

Give an example of phosphodiesterase inhibitors

A

Milrinone

47
Q

What is the mechanism of action of phosphodiesterase inhibitors

A

Inhibits the enzyme phosphodiesterase

48
Q

What is the normal role of phosphodiesterase

A

Break 2nd messenger CAMP

49
Q

How does calcium levels increase with phosphodiesterase inhibitors

A

Inhibiting phosphodiesterase increases CAMP
CAMP open calcium channels
Intracellular calcium therefore increases as calcium influx occurs

50
Q

What channel does verapamil effect

A

Voltage gated calcium channels

51
Q

What channel does lidocaine affect

A

Voltage gated sodium channel

52
Q

What channel does metropol affect

A

Beta 1 adrenoceptors

53
Q

What channel does amiodrone affect

A

Voltage gated potassium channel

54
Q

What are the 2 roles digoxin

A

Increase vagal activity

Partially inhibit sodium/potassium ATPase

55
Q

What channel does adenosine affect

A

Potassium channel

CVS (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions