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Echocardiography > Hemodynamics & Auscultation > Flashcards

Flashcards in Hemodynamics & Auscultation Deck (73)
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1
Q

event responsible for the first heart sound

A

closure of the AV valves

2
Q

event responsible for 75% of ventricular filling

A

rapid early filling in diastole

3
Q

event responsible for 10-30% of ventricular filling

A

end-diastole atrial contraction/atrial kick/late filling

4
Q

percentage of filling provided by early filling

A

75%

5
Q

percentage of filling provided by atrial contraction

A

10-30%

6
Q

event responsible for the second heart sound

A

closure of the semilunar valves

7
Q

cardiac phase that lengthens and shortens with heart rate

A

diastasis

8
Q

hibernation

A

reversible ischemia of a segment of heart wall

9
Q

normal amount of concentric thickening and contraction expected during systole

A

30%

10
Q

normal BP

A

120/80 mmHg

11
Q

high BP threshold

A

140/90 mmHg, taken on two occasions

12
Q

borderline high BP

A

130/85 mmHg

13
Q

low BP threshold

A

90/60 mmHg

14
Q

phase responsible for 2/3 of cardiac cycle

A

diastole

15
Q

phase responsible for 1/3 of cardiac cycle

A

systole

16
Q

fraction of cardiac cycle occupied by diastole

A

2/3

17
Q

fraction of cardiac cycle occupied by systole

A

1/3

18
Q

describe pulse pressure

A

difference in arterial blood pressure between systole and diastole

19
Q

formula for pulse pressure

A

BPsystole - BPdiastole

20
Q

describe mean arterial pressure

A

average arterial blood pressure over one full cardiac cycle

21
Q

formula for MAP

A

diastolic method: BPdiastole + (pulse pressure)/3
=BPdiastole + 1/3(BPsystole-BPdiastole)
systolic method: BPsystole + 2/3(BPdiastole)

22
Q

MAP

A

mean arterial pressure

23
Q

simplified Bernoulli’s equation

A

4v^2

24
Q

describe pressure gradient

A

difference in pressures btwn two adjacent locations in the heart, within the same cardiac phase

25
Q

formula for change in pressure along a flow path

A

simplified Bernoulli’s = 4v^2

26
Q

normal LV blood pressures, systole/diastole

A

100-140 / 3-12 mmHg

27
Q

normal RV blood pressures, systole/diastole

A

15-30 / 2-8 mmHg

28
Q

normal LA blood pressures

A

mean 2-12 mmHg

29
Q

normal RA blood pressures

A

mean 2-8 mmHg

30
Q

describe stroke volume

A

blood volume leaving ventricle per contraction

31
Q

formula for stroke volume using volumes

A

EDV-ESV

32
Q

describe cardiac output

A

blood volume leaving ventricle per minute

33
Q

formula for cardiac output

A

SV x HR

34
Q

describe cardiac index

A

blood volume leaving the ventricle per minute, relative to body size

35
Q

formula for cardiac index

A

CO/BSA

36
Q

BSA

A

body surface area

37
Q

normal stroke volume

A

70-100 mL

38
Q

normal cardiac output

A

4-8 L/min

39
Q

normal cardiac index

A

3-4 L/min^2

40
Q

formula for BSA

A

root of [weight(kg) x height(cm)]/60

41
Q

formula for stroke volume using LVOT measurements

A

CSA x VTI = πr^2 x VTI

42
Q

preload

A

end-diastolic volume and how it affects the length-tension relationship

43
Q

Frank-Starling Law

A

relates ability to stretch to contractility
more preload = larger ventricle = increased longitudinal stretching of the myocardial fibres = increased tension -> greater contractile force required for ejection

44
Q

What relationship is demonstrated by the Frank-Starling Law?

A

Length-Tension relationship of the ventricle

45
Q

formula for cross sectional area

A

πr^2

46
Q

Length-Tension relationship of the ventricle

A

relates ability to stretch to contractility
more preload = larger ventricle = increased longitudinal stretching of the myocardial fibres = increased tension -> greater contractile force required for ejection

47
Q

afterload

A

systemic resistance that the ventricles must pump against

48
Q

Interval-Strength relationship of the ventricle

A

relates time for ventricle to fill vs strength contraction required (interval-strength)
affects HR: longer interval btwn heartbeats = increased preload, results in stronger contraction required for ejection

49
Q

describe inotropic force

A

relates contractile force to contractile speed (force-velocity):
force required for ejection affects the velocity of ventricle muscle fibre contraction

50
Q

describe chronotropic force

A

relates time for ventricle to fill vs strength contraction required (interval-strength)
affects HR: longer interval btwn heartbeats = increased preload, results in stronger contraction required for ejection

51
Q

Which maneuver can be used to decrease venous return, stroke volume, and cardiac output?

A

Valsalva maneuver

52
Q

Which maneuver can be used to increase venous return, stroke volume, and cardiac output?

A

amyl nitrate inhalation

53
Q

Force-Velocity relationship of the ventricle

A

relates contractile force to contractile speed (force-velocity):
force required for ejection affects the velocity of ventricle muscle fibre contraction

54
Q

factors that affect afterload

A
viscosity
arterial resistance (systemic BP, HTN)
vascular geometry (stenosis, structural anomalies)
valvular geometry (stenosis, structural anomalies)
55
Q

factors that affect contractility/inotropic force

A

increased inotropic force: medications

decreased inotropic force: disease, hypertrophic or fibrosed heart muscle, hypoxia

56
Q

factors that affect chronotropic force

A

increased chronotropic force: adrenaline (sympathetic nervous system)
decreased chronotropic force: medications, relaxation, high fitness level

57
Q

phases of systole

A

isovolumic contraction time, ventricular systole

58
Q

phases of diastole

A

isovolumic relaxation time, early filling, diastasis, late filling

59
Q

normal IVCT

A

30-50 ms

60
Q

normal systolic ejection time

A

300 ms

61
Q

In which direction does the muscle contraction progress through the ventricle during systole?

A

apex to base

62
Q

normal aortic blood pressure, systole/diastole

A

100-140 / 60-90 mmHg (systole matches LV pressures)

63
Q

What marks the transition between IVCT and systole, causing the aortic valve to open?

A

The LV to aorta pressure gradient must be exceeded.

The rising IVCT pressures in the LV exceed the diastolic aortic pressure (Ao dia 60-90 mmHg, usually around 80)

64
Q

What marks the transition between systole and IVRT, causing the aortic valve to close?

A

The LV to aorta pressure gradient must fall.

The risen systolic pressures in the Ao exceed the emptied LV pressure (Ao sys 100-140 mmHg)

65
Q

normal IVRT

A

50-100 ms

66
Q

What marks the transition between IVRT and diastole, causing the mitral valve to open?

A

The LA to LV pressure gradient must be exceeded.

The rising filling pressures in the LA exceed the LV pressure (LA mean 2-12)

67
Q

What marks the transition between diastole and IVCT, causing the mitral valve to close?

A

The LA to LV pressure gradient must fall.

The risen IVCT pressures in the LV exceed the emptied LA pressures.

68
Q

normal early filling time

A

150-250 ms

69
Q

What occurs during diastasis?

A

atrioventricular pressure gradient equalizes very briefly, dependant on heart rate

70
Q

normal diastasis time

A

variable, dependant on heart rate

71
Q

normal late filling time

A

???

72
Q

normal pulmonary artery pressure, systole/diastole

A

15-30 / 4-12 mmHg

73
Q

normal RVSP

A

under 35 mmHg