Cardiovascular Problems L9 Flashcards Preview

Medsci 142 Test 1 > Cardiovascular Problems L9 > Flashcards

Flashcards in Cardiovascular Problems L9 Deck (72):
1

What is another name for mitral regurgitation?

Mitral incompetence

2

What does the condition of Mitral regurgitation consist of?

when the Mitral valve Doesn't close tightly
This results in the blood Flowing Backwards (back flow) up into the atria

3

What causes mitral regurgitation?

Dilated Cardio Myopathy

4

Does mitral regurgitation cause dilated cardio myopathy or does dilated cardiomyopathy cause mitral regurgitation?

Dilated Cardiomyopathy (the physical lengthening of Myocytes and following dilation of high pressure Left side of lumen and without growing flaps) causes Mitral regurgitation

5

What does dilated cardio myopathy translate to?

"Cardio" = heart
"myo-" = muscle
"pathy" = disease
resulting in "dilation"

6

What is dilated cardio myopathy?

A disease of the hear muscle caused by dilated ventricle

7

What is the cause of dilated cardio myopathy?

IDOpathic: the cause is unable to be identified
But Possibly :
1. drugs (e.g. steroids) (toxins)
2. alcohol (metabolites attack muscle tissue) (toxins)
3. Viral infection - in many cases
-all cause death and/or damage to the heart wall

8

What does idiopathic mean?

the cause is unable to be identified

9

What are the 3x potential causes of Cardiomyopathy?

1. drugs (e.g. steroids) (toxins)
2. alcohol (metabolites attack muscle tissue) (toxins)
3. Viral infection - in many cases
-all cause death and/or damage to the heart wall
-otherwise idiopathic - non-identified cause

10

Which biological changes occur during dilated cardio myopathy?

1.the Infected muscle tissue are Attacked by lymphocytes.
-many of the fibres Die
-whilst the other damaged fibres are weakened and Slow to contract
-altogether the Myocytes LENGTHEN - for an unknown reason
2.High pressure circuit is most affected - LV
3. LV dilates as the Myocytes LENGTHEN, resulting in an Enlarged chamber/lumen, and a normal wall thickness (max only a slight increase in wall thickness)
4. Fibrous rings of the fibrous skeleton Also increase, but the mitral valve flaps Don't increase.
5. Therefore the Mitral valve flaps No Longer Meet during Systole, resulting in leakage/back flow by the mitral valve back up into the atria, and therefore Mitral Regurgitation

11

What happens to the muscle fibres during dilated cardio myopathy?

some muscle cells/Myocytes DIE
some muscle cells/Myocytes are DAMAGED and therefore weakened and Slower to contract
the INFECTED muscle tissue is ATTACKED BY LYMPHOCYTES
-overall the Myocytes LENGTHEN -for an unknown reason

12

What happens to the fibrous skeleton during dilated cardio myopathy?

The fibrous skeleton also increases/stretches out with the mitral hole

13

What happens to the valve flaps during mitral regurgitation?

Valve Flaps/cusps DO NOT grow
therefore the valve flaps free edges do not meet during systole (contraction)
resulting in backflow of blood by the mitral inlet valves back UP into the L Atria

14

What cause the dilation in dilated cardio myopathy?

The lengthening of the Lymphocyte attacked Myocytes due to the idiopathic causes

15

Do lymphocytes have a role in dilated Cardio Myopathy?

yes
The Lymphocytes attacked the infected muscle tissue
some muscle tissue dies
some muscle tissue is weakened and slow to contract
overall there is LENGETHENING of the muscle fibres - which causes the dilation of the high pressure circuit (left)
-causes the HYPERTROPHY (enlargement) of the heart -lumen only, not wall thickness

16

What does Hypertrophy mean?

increase in size

17

Does the heart undergo hypertrophy in Dilated Cardiomyopathy?

Yes
the heart does increase in size
it is the Lengthening of the cardiac Myocytes which causes the dilation of the high pressure LV

18

What sort of Hypertrophy occurs during Dilated cardiomyopathy?

Hypertrophy (enlargement of the heart) Does occur
the Wall thickness remains the same (LV:RV 3:1),
However the Lumen radius/size increases

19

What happens to the wall thickness in dilated cardio myopathy's hypertrophy(enlargement) of the heart?

Wall thickness remains the same (LV:RV 3:1)

20

What happens to the lumen radius in dilated cardio myopathy's hypertrophy(enlargement) of the heart?

Lumen Radius INCREASES in a dilated cardiomyopathic heart

21

Why is it a problem that the lumen of the heart enlarged and the wall thickness remains the same?

dilation /Lumen increase= heart is able to contain a greater volume of blood(due to larger radius)= heart is bigger/hypertrophy
but this increased blood volume can only be Pumped Out under the LOWER Pressure -due to Law of Laplace :same wall thickness and larger radius
Therefore overall the LV is weaker
-more blood of which the heart has to move, and to do so with the same thickness (and LESS pressure/force generated-due to Law of Laplace) - therefore overall weaker
Law of Laplace= Pressure (generated by the heart) Proportional to 1/radius
= shows that is the heart is bigger/lumen dilated and large, but the wall thickness doesn't change, the heart is weaker, and can not generated AS MUCH /generates LESS pressure
- CO is responsible for maintaining MABP, but now Decreased CO due to Volume Load (having to push new blood + regurgitated blood every cycle + having a bigger lumen, therefore more blood coming into it/filling)

22

What is the Law of LaPlace?

Pressure (generated by the heart) is proportionate to 1/ radius

23

What does the Law of Laplace mean in relation to dilated cardiomyopathy?

Pressure (generated by the heart) Is proportional to 1/radius
-Same wall thickness, larger lumen size due to Myocytes lengthening of the high pressure Left circuit especially
- Increase in radius = smaller pressure generated
-smaller pressure/ejection force, even tho Larger lumen ad therefore larger volume of blood coming in = VOLUME LOAD
= decreased CO and therefore harder to maintain MABP through CO

24

Does dilated cardiomyopathy have a law related to it?

Yes Law of Laplace
-Pressure(generated by the heart) is proportional to 1/Radius

25

What are the comparisons between the Mitral valve and Fibrous Skeleton in a normal vs. dilated cardiomyopathic heart?

Normal heart:
Inlet valve Cusps close and seal. Fibrous skeleton fully supportive and complete. Normal CO, able to maintain MABP
Dilated Cardiomyopathic Heart:
Hypertrophic lengthening of cardiac Myocytes. Fibrous skeleton stretching with dilated lumen of LV. Cusps remain same size/DONT get bigger. Cusps no longer meet during ejection/systole/when inlet valve attempts to close. Regurgitation during Systole/Ventricular Contraction/Ejection. Volume load, NOT able to maintain CO and therefore has to work harder to maintain MABP (volume load and viscous cycle)

26

Does dilated cardiomyopathy effect the inlet or outlet valves more?

Inlet valve of Left High pressure circuit more
Left inlet valve = Mitral valve
therefore Mitral Regurgitation

27

What does the High pressure circuit consist of?

Entirety of the LEFT side
as we are talking about ONE circuit which I High pressure
therefore Mitral inlet valve + Aortic outlet valve
-both surrounding the LV

28

What is the mitral valve and fibrous skeleton like in a normal heart?

Normal heart:
Inlet valve Cusps close and seal. Fibrous skeleton fully supportive and complete
Normal CO, able to maintain MABP

29

What is the mitral valve and fibrous skeleton like in a dilated cardiomyopathic heart?

Dilated Cardiomyopathic Heart:
Hypertrophic lengthening of cardiac Myocytes. Fibrous skeleton stretching with dilated lumen of LV. Cusps remain same size/DONT get bigger. Cusps no longer meet during ejection/systole/when inlet valve attempts to close. Regurgitation during Systole/Ventricular Contraction/Ejection. Volume load, NOT able to maintain CO and therefore has to work harder to maintain MABP (volume load and viscous cycle)

30

Which 2x methods can you detect Dilated Cardiomyopathy?

1. Ultra sound -listen for different echo/feedback from different densities of tissue
2. Doppler Ultra sound = shows the way that fluid is moving (superior movement of fluid (back up into atria) during systole shows mitral regurgitation)

31

When can Ultrasound/Doppler ultrasound be used?

Dilated cardio myopathy
Ultrasound can show different densities of tissue for orientation
Doppler:shows the way that fluid is moving
(superior movement of fluid (back up into atria) during systole shows mitral regurgitation)

32

What is shown on the Doppler Ultra sound in a dilated cardiomyopathic heart?

shows the way that fluid is moving (superior movement of fluid (back up into atria) during systole shows mitral regurgitation)

33

What are some exterior physical differences between a sheep heart and a dilated cardiomyopathic heart?

Sheep heart: 1.Heart is the size of a Clenched fist 2. Non-Flabby and Non-collapsed walls 3. Does hold its shape
Dilated Cardiomyopathic heart: 1. Heart size is much larger the clenched fist (hypertrophy) 2. Flabby walls, often Collapsed 3. Heart doesn't hold its shape

34

What are some exterior physical observations of a normal sheep heart?

Sheep heart:
1.Heart is the size of a Clenched fist
2. Non-Flabby and Non-collapsed walls
3. Does hold its shape
-dilated cardiomyopathic heart is negatively opposite to this

35

What are some exterior physical observations of a dilated cardiomyopathic heart?

Dilated Cardiomyopathic heart:
1. Heart size is much larger the clenched fist (hypertrophy)
2. Flabby walls, often Collapsed
3. Heart doesn't hold its shape
-normal heart is positively opposite this

36

What is Auscultation?

The act of listening to sounds of the body using a stethoscope
-Valve sounds radiate to specific areas of the chest
Heart sound is best hear Away from the valves, closer to Where the blood is Flowing Towards
Tricuspid valve = Below inlet, to the Right
Mitral valve = Below inlet, to the Left
Outlet = above in the arteries
Mitral Regurgitation = Left Atrium

37

What is the name for the method of listening to the sounds of the body using a stethoscope?

Auscultation

38

What causes the sounds of the heartbeat?

Is the stopping of blood itself, DUE to the closing of the heart valves, which CAUSES the turbulence/oscillations/vibrating of the heart wall/blood

39

When can you hear no heart sounds?

When the blood is flowing smoothly
smooth flowing blood = silent

40

What is the first heart sound associated with?

Blood turbulence: associated with closure of AV atrio-ventricular valves
Soon after ventricular systole begins

41

What is the second heart sound associated with?

blood turbulence: associated with the closure of BOTH SL semi-lunar valves
At the beginning of Ventricular Diastole

42

Which heart sound do you heart at the beginning of ventricular systole?

first heart sound
As this is when the inlet valve closes -preparing for ejection

43

Which heart sound do you heart at the beginning of ventricular diastole?

Second heart sound
As this is when the outlet valves closes - preparing for filling

44

When is the first heart sound heard?

Just after the beginning of ventricular systole/ejection
-as the inlet valve closes (for ejection)

45

When is the second hear sound heard?

Just after the beginning of Ventricular Diastole
-as the outlet valves close (for filling)

46

Where do you listen for the heart sound during stethoscope use/auscultation?

Tricuspid valve = Below inlet, to the Right
Mitral valve = Below inlet, to the Left
Outlet = Above, in the arteries
Mitral Regurgitation = Left Atrium

47

Where do you listen in auscultation for the flow of blood through the Tricuspid valve?

Below inlet, to the Right

48

Where do you listen in auscultation for the flow of blood through the Bicuspid/Mitral valve?

Below inlet, to the Left

49

Where do you listen in auscultation for the flow of blood through the Outlet valves ?

Above, in the arteries

50

Where do you listen for the flow of blood in Auscultation during Mitral regurgitation?

up in the LA left atrium

51

What are heart murmurs?

abnormal sounds of clicking, rushing or gurgling
can be heard between, before or after heart sounds
-in children 2-4 this is very common - are "functional"/innocent heart murmurs

52

What are the abnormal sounds of clicking, rushing or gurgling called?

Heart murmurs
Can be heart between, before or after heart sounds

53

What is the major symptom of Dilated Cardiomyopathy?

Breathlessness =shortness of breath
-due to the Lung tissue being waterlogged and fluid filled, resulting in shortness of breath

54

Why is the major symptom of Dilated Cardiomyopathy Breathlessness?

Lung tissue is fluid filled/water logged
Results in a shortness of breath=breathlessness

55

Where is blood re-pressurised?

at the Ventricles
Blood is re-pressurised in order to drive the blood off into another circuit, travelling Down its pressure gradient
-re-pressurising is due to contraction

56

Why do the ventricles re-pressurise blood?

so that the blood can be driven through another circuit, travelling Down its pressure gradient

57

What is breathlessness?

Shortness of breath

58

What is the absolute requirement of blood flow?

Pressure gradient
blood must flow DOWN a pressure gradient

59

What happens at the arterioles at a normal heart?

Arterioles take a lot of pressure out of the blood (have the greatest resistance across them) as they are protecting the capillaries which follow them/post-ceed them
Greatest pressure drop/difference

60

What happens immediately as the blood flows out of the LV into the aorta?

Some friction occurs, and there is Decreased resistance
Therefore the pressure decreases a little (100 --> 90mmHg now)

61

How is a normal heart coping?

Pushing out normal CO ever cycle
In order to maintain MABP in the systemic arteries = to drive all the circuits

62

Why do we need to maintain MABP?

To drive all the circuits

63

What does CO maintain?

MABP

64

What maintains MABP mean arterial blood pressure?

CO constant cardiac output

65

What is Dyspnoea?

Discomfort/conscious Laboured breathing
=struggling to ventilate lungs/fill lungs with heart
due to the decreased compliance of lungs- which are Fluid filled and waterlogged

66

What causes dyspnoea?

Difficulty VENTILATING lungs
due to the decreased compliance of the fluid filled water logged lungs

67

What is the term for laboured/discomfort in breath due to decreased ability to ventilate lungs due to increased rigidity/decreased compliance of lungs to expand?

Dyspnoea

68

What is the vicious cycle in mitral regurgitation?

Positive Feedback system (another even occurs to control it) - perpetuates cycle and makes it worse
1. Cardiac muscle disease (viral or other causes)
2. LV dilation (weakened (when contracting) tissue and lengthening of Myocytes)
3. Mitral valve ring stretches (valves fail to seal even more)
4. Increased mitral regurgitation
5. Volume Load on LV
2.3.4.5. continually. until...
LV fails (i.e. death) - unable to maintain MABP, resulting in organ failures, and body/systems are unable to support itself

69

What happens to the lung tissue when it is less compliant?

Lung tissue is water filled, due to capillaries increasing their leakage of blood plasma into the interstitial fluid (double exchange) increasing the rigidity of the lung tissue , therefore harder to inflate/ventilate lungs, conscious laboured /discomfort breathing

70

What happens when MABP cannot be maintained?

Organ failure
Systems are cannot/are unable to support itself

71

Why can organ failure and the body's inability to support itself occur?

When CO gets so low (e.g. due to volume load and vicious cycle of mitral regurgitation due to dilated cardiomyopathy occurs) that MABP mean arterial blood pressure can no longer be maintained

72

What is a treatment for dilated cardiomyopathy?

Artificial valve
-ball value now St Judes valves