Brainscape's Knowledge GenomeTM

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


See full index

Medicine yr1 > CVS-cardiac cycle and BP > Flashcards

CVS-cardiac cycle and BP Flashcards

1
Q

what is the definition of blood pressure?

A

the measurement of the force against the walls of the arteries

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

what is blood pressure measured in?

A

mmHg

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

what is the definition of systolic pressure?

A

maximum arterial (aortic) pressure during left ventricular contraction

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

what is the definition of diastolic pressure?

A

Minimal arterial (aortic) pressure during left ventricular relaxation

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

what is pulse pressure?

A

strength of contraction

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

how would you work out pulse pressure?

A

systolic- diastolic= PP

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

how would you work out mean arterial pressure?

A

diastolic pressure -1/3 pulse pressure

or

CO x systematic vascular pressure

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

why is mean arterial pressure important?

A

the heart does not spend an equal amount of time in systole and diastole

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

what proportion of time does the heart spend in diastole?

A

2/3

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

what proportion of time does the heart spend in diastole?

A

1/3

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

how would you measure blood pressure?

A

cardiac output x peripheral resistance

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

how would you measure cardiac output?

A

stroke volume x heart rate

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

what is the normal value for cardiac output?

A

~5L/min

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

how would you work out stroke volume?

A

end diastolic volume (EDV) - end systolic volume (ESV)

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

what is the equation for working out ejection fraction?

A

stroke volume/ EDV

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

what is the normal range for ejection fraction in a healthy person?

A

55-75%

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

what is stroke volume?

A

Amount of blood transferred from left ventricle to the aorta in systole.

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

which 3 factors is stroke volume dependent on?

A
  • preload
  • contractility
  • afterload
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is preload?

A

volume of blood that the ventricle has available to pump

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

what is contractility?

A

force that the muscle can contract with

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

what is afterload?

A

the arterial pressure (aorta) against which the (left) ventricle will contract against

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

what is the end diastolic volume (EDV)?

A

Total volume of blood left in the ventricle at the end of diastole

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

what is EDV dependent on?

A

preload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is end systolic volume (ESV)?

A

Total volume of blood left in the ventricle at the end of systole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is ESV dependent on?

A

contractility + afterload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

does the LV ever empty at the ends of systole?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what should the SV be in a healthy person?

A

> 60ml

28
Q

outline the 7 phases of the cardiac cycle.

A

1-Atrial systole / Ventricular Diastole

2-Isovolumetric contraction (pressure increases without a change in volume)

3-Rapid ejection of blood out of the ventricles

4-Reduced ejection of blood out of the ventricles

5-Isovolumetric relaxation (pressure decreases without a change in volume)

6-Rapid filling

7-Reduced filling (diastasis)

29
Q

With regards to afterload:

A-It refers to the mean arterial pressure in the systemic vasculature

B-It refers to the left ventricular end-diastolic pressure

C-It refers to the jugular venous pressure

D-It refers to the pressure the heart must work against to eject blood during systole

E-It refers to myocardial contractility

A

D

30
Q

With regards to ejection fraction:

A-In a normal healthy heart, ejection fraction is ~33%

B-In a normal healthy heart, ejection fraction is 100%

C-It describes the remaining volume of blood in the ventricle at the end of systole

D-It describes the remaining volume of blood in the ventricle at the end of diastole

E-It can be calculated by dividing Stroke Volume by End Diastolic Volume

A

E

31
Q

which 2 mechanisms control blood pressure?

A
  • endocrine (RAAS)

- neuronal

32
Q

which mechanism of BP control is longterm?

A

endocrine-RAAS

33
Q

which mechanism of BP control is short term?

A

neuronal

34
Q

which cells sense a decreased flow/ NaCl (indicative of low BP) concentration?

A

Macula Densa cells of the ascending Loop of Henle in the kidneys

35
Q

which cells secrete renin in response to detected low BP (by macula densa cells)?

A

juxtaglomerular granular cells

36
Q

what is the role of renin in the RAAS system of BP control?

A

The enzyme renin converts angiotensinogen (released by the liver) to angiotensin I.

37
Q

which enzyme converts angiotensin I to angiotensin II?

A

ACE-released by lungs

38
Q

which hormone of the RAAS system has widespread, systemic effects which increase BP?

A

Angiotensin II

39
Q

outline the effects of angiotensin 2

A
  • Cardiac and vascular hypertrophy
  • Systemic vasoconstriction
  • Acts on Adrenal Cortex (Zona Glomerulosa) to release Aldosterone->increases kidney NaCl + H2O retention (increase BP)
  • Acts on the posterior pituitary gland to release ADH-> increases kidney NaCl + H2O retention
40
Q

where is the cardiovascular centre located?

A

medulla oblongata

41
Q

what does the cardiovascular centre regulate?

A
  • heart rate

- stroke volume

42
Q

what are the 3 types of input sensory receptors?

A
  • proprioceptors
  • baroreceptors
  • chemoreceptors
43
Q

what is the role of proprioceptors?

A

increase heart rate if there is an anticipation for increase in heart rate, e.g. before exercise

44
Q

what do baroreceptors detect?

A

changes in blood pressure

45
Q

what do chemoreceptors detect?

A

chemoreceptors

46
Q

does the sympathetic nervous system increase or decrease BP?

A

increase BP

47
Q

does the parasympathetic nervous system increase or decrease BP?

A

decrease

48
Q

what do cardiac accelerator nerves of SNS control?

A

SAN
AVN
chambers

49
Q

how do cardiac accelerator nerves of SNS control the heart?

A

releasing noradrenaline that acts on β1 adrenoreceptors.

50
Q

what are the SNS effects on the heart?

A

-Increase heart rate (positive chronotropic)

-Increase contractility
(positive inotropic)

  • Increase CO
  • Cause peripheral vasoconstriction
51
Q

how does the SNS increase HR?

A

speeds up the rate of spontaneous depolarisation of pacemaker cells

52
Q

how does the SNS increase contractility?

A

-increasing CO->increases Ca2+ influx when the L-Type Ca2+ channels are open in contractile cells, thereby increasing contractility

53
Q

does the SNS cause peripheral vasoconstriction or vasodilation?

A

peripheral vasoconstriction

54
Q

how does the SNS cause peripheral vasoconstriction?

A

via α1 adrenoreceptors

55
Q

what is a positive chronotropic effect?

A

increase heart rate

56
Q

what is a positive inotropic effect?

A

increase contractility

57
Q

what is the effect of the parasympathetic NS on BP?

A

act to decrease BP

58
Q

through which nerve does the parasympathetic NS control the heart?

A

The Vagus Nerve (CN X)

59
Q

which heart structures does the parasympathetic NS control?

A

SAN

AVN

60
Q

which hormone is associated with the PSNS?

A

acetylcholine

61
Q

which receptor does ACh bind to in the PSNS?

A

M3 muscarinic receptors

62
Q

what is the effect of the PSNS on heart rate?

A

Decrease heart rate (negative chronotropic effect) (slows the rate of spontaneous depolarisation of pacemaker cells)

63
Q

what is the effect of the PSNS on contractility?

A

Little effect on contractility (As most CN X fibres terminate in the nodes and atria – no effect on the ventricles)

64
Q

What does renin produce angiotensin 1 from?

A-Angiotensin 2
B-Angiotensinogen
C-ACE
D-Aldosterone
E-ADH
A

B

65
Q

What gland releases ADH?

A-Adrenal Gland
B-Posterior Pituitary Gland
C-Hypothalamus
D-Anterior Pituitary Gland
E-Salivary Gland
A

B

66
Q

Which receptors do noradrenaline and acetylcholine act on in relation to BP control?

A-B1 adrenoreceptor
B-B2 adrenoreceptor
C-M1 muscarinic receptor
D-M2 muscarinic receptor
E-M3 muscarinic receptor
A

E

Medicine yr1 (55 decks)

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