Brainscape's Knowledge GenomeTM

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


See full index

MedSci142 > Lecture 9 - Cardiovascular Problems > Flashcards

Lecture 9 - Cardiovascular Problems Flashcards

1
Q

What is Mitral Regurgitation?

A

also called Mitral Incompetence

when the Mitral Valve DOESNT CLOSE tightly and the blood Flow Backwards, INTO the heart

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

What is Dilated Cardiomyopathy?

A

“-pathy” = pathology/disease of

a disease of heart muscle caused by dilated ventricles

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

What does idiopathic mean?

A

UNABLE to identify Origin of a condition

often case with dilated cardiomyopathy

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

What is the cause of Dilated Cardiomyopathy?

A

cause is often unable to be identified as idiopathic but possibly,
Drugs (e.g. steroids)(antibiotics)
Alcohol (metabolites of broken down alcohol is still toxic to muscle cells (cardiac and skeletal espec.))
Viral Infection

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

What do alcoholics sometimes get?

A

Beer Belly
Untoned arms and legs (toxic metabolites eat away at muscle)
Beer Heart

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

What is hepatitis?

A

A virus which attacks the liver

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

What occurs during dilated cardiomyopathy?

A

Infected muscle fibres are Attacked by lymphocytes, many die and others are left Weakened and Slow to contract
LV DILATES due to REMAINING HEART MUSCLE LENGTHENS
LV is Most affected because of High Pressure
Resulting in Enlarged Chamber with wall thickness being Normal or Slightly Increased(LV3:1 RV still)(bigger lumen but same wall size)
the Fibrous Ring supporting mitral valve Stretched
Mitral flaps No longer meet during Systole causing mitral regurgitation

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

What happens during Left Ventricle Dilation? During which condition?

A

Dilated Cardiomyopathy
Normal heart = LV:RV wall thickness 3:1
LV dilation = LV:RV wall thickness 3:1
Dilation of ventricle due to LENGTHENING of cardiac muscle fibres
Ratio of wall thickness is the same (relatively thinner)
However the RADIUS of LUMEN increases
MORE BLOOD that heart has to move but can only do so with Same Thickness
Law of LaPlace

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

What is the Law of LaPlace?

A

Pressure of the heart can generate proportional 1/radius (inversely proportional to radius)
wall stress = (Px r)/(2w)
heart is BIGGER but wall thickness doesn’t changes
so heart is WEAKER = cannot generate as much pressure

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

What happens to the Mitral Valve during Dilated Cardiomyopathy?

A

Normal Heart: Complete fibrous Heart to REINFORCE the valve. During Ventricular Ejection, the Inlet valves are closed as pressure trying to loft leaflets up and the free edges are together and Closed. the Outlet Valves remain Open to Eject Blood.

LV Dilation: due to lengthening of cardiac muscle fibres(hypertrophy) the LV is ENLARGED and the Fibrous RING of the mitral valve is STRETCHED
However, flaps DONT get Bigger to compensate even though opening is dilated, so the Mitral Valve Cusps NO LONGER MEET when the valve attempts to close. so during Systole, blood REGURGITATES from LV–>LA

Can use Ultra sound to detect direction of blood flow

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

How can Ultra Sound be used in Dilated Cardiomyopathy?

A

can detect and show the direction of blood flow

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

What is the relationship between the dilation of the ventricle and fibrous skeleton?

A

the fibrous skeleton of the heart dilates as the ventricle dilates
should “REINFORCE” the valve (esp. mitral)

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

What is another name for Mitral Regurgitation?

A

Mitral Incompetence

Mitral valve “doesn’t work” it is “ incompetent”

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

How is pressure affected by Dilated Cardiomyopathy?

A

Atrial pressure should rise during ventricular ejection
A: X Atrial pressure is Consistently HIGH - there is NO spike Mitral Stenosis
B: YES: Ventricle squeezes trying to Push blood to the aorta but some goes to the atrium (decrease in ventricular pressure) (increase in arterial pressure)
C: X ventricular pressure much higher than aorta. Narrowing of OV Aortic Stenosis
(separation fo ventricular pressure from aortic pressure) (no effect on atrial pressure (no spike))

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

What does a heart with Dilated Cardiomyopathy look like?

A

Walls are Floppy and Sunken In (dilated)
Walls thickness same(maybe a little thinner)
Huge lumen (drastically increased to a dangerously large heart)
Larger than clenched fist

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

How can you detect Dilated Cardiomyopathy?

A

Listening for heart murmurs

More sophisticated: Doppler ultrasound

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

What are the heart sounds of a heart with Dilated Cardiomyopathy?

A

Pan-systolic Murmur- Ventricular ejection

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

What does Doppler Ultrasound consist of?

A

More sophisticated manner of detecting Dilated Cardiomyopathy
give you a colour code which tells you which direction fluid is flowing
orange = flowing inferiorly(diastole)
blue= flowing superiorly(systole)

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

What are the heart sounds for A, B and C and which one is correct for mitral regurgitation?

A

X A = lub- shhhhh
delay in murmur = gets Louder, and Overlaps 2nd heart sound when Filling (after)

YES B= lub- shhhhh - dub
mitral regurgitation as IV closed and blood squirted back into atria - sound during ejection and stops during relaxation (filling)

X C= lub dub shhh
nothing during ejection, but noise during filling
blood down from aorta or interference between atria/ventricle (wrong part of cycle)

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

What part of the cycle does Mitral Regurgitation occur?

A

Ventricular Ejection

when the ventricle is pressurising (rise in v. pressure) the blood

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

What is Aortic Stenosis?

A

Narrowing Outlet

Ventricle has to work harder, to generate More pressure, to squeeze blood through the narrow outlet

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

What is Mitral Stenosis?

A

Atrial pressure is consistently high
(no spike)
murmur occurs during the RELAXATION period between S2 - next S1

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

What are Heart Murmurs?

A

Abnormal sounds of CLICKING, RUSHING or GURGLING noise which is heard BEFORE or AFTER normal heart sounds

in children (2-4) this is very common (FUNCTIONAL heart murmurs/Innocent)

Listen for TURBULENCE generated Outside of the normal Heart Rhythm
(when valves close)

24
Q

What can generate turbulence/heart murmurs in the heart sound?

A

Mitral regurgitation

25
Q

When is the heart sound of Ejection?

A

Between the first and second heart sound
S1->S2
(just contraction)
is what is important in mitral regurgitation

26
Q

When is the heart sound of Filling?

A

Between the second and first heart sound
S2-.next S1
(just relaxed)

27
Q

What is Auscultation?

A

The act of LISTENING to sounds within the body using a Stethoscope

28
Q

What is the sound of a heart beat?

A

Stopping of blood due to closing heart valves
therefore = turbulence
(as smoothly flowing blood is silent)

29
Q

What is the sound of smoothly flowing blood?

A

silent

30
Q

What is the sound of Stopping blood?

A

turbulence
after inlet valves close = lub
after outlet valves close = dub

31
Q

How many heart sounds are there?

A

4

yet only 2x heart sounds are loud enough

32
Q

What is the first loud heart sound representative of?

A

blood Turbulence associated with the Closure of AV valves soon after Ventricular Systole begins
best heard BELOW valve (is past inlet valve)
to LEFT = mitral louder
to RIGHT = tricuspid

33
Q

What is the second loud heart sound representative of?

A

blood Turbulence associated with the Closure of BOTH SL valves at the Beginning of Ventricular Diastole
best heart ABOVE/SUPERIOR valve (past inlet valve)

34
Q

Where are heart sounds best heard?

A

heart sounds are usually best heard from locations Different to the location of the valves, more where the BLOOD is FLOWING TOWARDS

35
Q

Where is the best location to least for heart murmurs caused by mitral regurgitation?

A

Ejection
therefore listen for Around ATRIUM
wssshhh sound

36
Q

Are heart murmurs ever common?

A

YES
in children (2-4)
FUNCTIONAL heart murmurs/Innocent

37
Q

What is Stenosis?

A

the heart murmur is heard when the VALVE SHOULD be FULLY OPEN BUT ITS NOT

(mitral stenosis, murmur is during relaxation period b/w S2 and next S1)

38
Q

What is Incompetence?

A

heart murmur is the heart when the valve SHOULD BE FULLY CLOSED but it is not

(mitral incompetence, murmur occurs during Ventricular Systole between S1-S2)

39
Q

What is Mitral Incompetence?

A

heart murmur occurs during Ventricular SYSTOLE (CONTRACTION) between S1-S2

40
Q

What are heart sounds useful as?

A

Heart sounds are a useful Diagnostic Tool

41
Q

What is a common symptom of Mitral Regurgitation?

A

Breathlessness

42
Q

Why can patients with Mitral Regurgitation have breathlessness?

A

LUNGS and TISSUE become WET (fluid filled) and shortness of breath results

43
Q

Why does the problem of the Left Systemic side cause symptoms in Right/Pulmonary side?

A

Normal Mean Blood pressures:
Veins are LOW in pressure
Arterioles have Lots of pressure taken OFF (Greatest pressure drop) tight control
By the time Blood gets back RA very low pressure
RV RE-pressurises
LA low
To drive this process must have a Pressure GRADIENTthrough circuits
Normal:
1. HP pushing blood out into arteries arterioles capillaries vienoles veins (LP down the circuit)
2. this ensure that the directionality of blood flow is Always Down the circuit
3. same in both systemic and pulmonary circuit
4. could argue the heart’r role is to depressurise below venous blood up to arteriole pressure and push it through the circuit, in a rhythmic pulsatile manner

Mean Blood pressures with mitral regurgitation:
Have a dilated heart and therefore a dilated ventricle, caused fibrous ring to stretch, gives a dilated valve opening, causing mitral regurgitation.
Heart is still coping.
Problem: every time ventricle contracts (ejection), has to push both normal CO into the arteries to maintain mean arteriole pressure, lose some of the blood back into atrium, Increasing Left Atrial pressure, causing pressure to Backlog up throughout the pulmonary circuit.
Therefore in order for blood to flow from Pulmonary Veins into the Atrium it too has to increase in pressure. Pressure in capillaries –> veins also is Higher Fluid leaks out and is reabsorbed into the capillaries.
Hydrostatic pressure drives fluid out of your capillaries. More blood will be pushed out of the capillaries and into the pulmonary circuit. Capillaries leak MORE. so much so that the Capillaries and Lymphatic system Cannot Reabsorb, resulting in Saturation of tissues.
This effects the Compliance of the lungs, how easily they Stretches, how easily it fills with air.
+
LV has to pump more blood. pumps CO + what it leaks back.= Volume Load onto the Left Ventricle

44
Q

Which side has symptoms when there is a problem in the Left Systemic side?

A

Right/Pulmonary side

45
Q

What is hydrostatic pressure?

A

the pressure which drives fluid out of your capillaries

“ blood pressure”

46
Q

What happens when you have saturation of tissues?

A

Have the excess tissue fluid outside surrounding the cells (not reabsorbed)
due to Capillaries leaking more

47
Q

What is a volume load?

A

CO (needed to be pumped to maintain atrial pressure)+ fluid which leaks back due to dilated valve/skeleton/mitral regurgitation pumped every diastole
Not a pressure load
Has to pump more blood in every cardiac cycle. relative to every prior cycle.

48
Q

What is a summary of

A
  1. during systole, as much as half the blood ejected by the left ventricle is regurgitated into the left atrium
  2. during the next diastole the regurgitated blood returns to the ventricle + fresh blood from pulmonary veins
  3. Then to maintain CO, the LV must either pump a greater volume or generate a greater pressure (has volume load on it currently)
  4. Assuming heart rate stays the same, LV volume at end of filling must increase,
  5. inorder to fill the LV, the LA is going to have to work harder (more blood in it, try and help LV by topping it up more)
  6. LA increase
  7. Pulmonary Venous pressure Increase
  8. Pulmonary Capillary pressure increase
  9. Pulmonary Capillary Leakage will increase (seen in alveolus)(ore fluid forced out of the capillaries into the alveoli and around the tissue)
  10. excess surrounding fluid and alveoli fluid = wetter lungs
  11. Lungs become Heavier (and wetter) (instead of lighter and drier)
  12. Lungs become more rigid (waterlogged and soggy)
  13. Oedema =Push fluid into tissue without draining away properly
  14. requires more muscular work
  15. suffers from Dyspnoea (difficulty breathing, laborious and wheezing, struggling to suck air in and out due to the lungs having decreased in compliance (duet Oedema))
  16. IF cardiomyopathy (diseased lung) has stemmed from a Viral infection, Cardiac muscle fibres lengthened= LV dilated+ fibrous ring stretch= leaky valve= mitral regurgitation = V work harder= develops volume load on LV, as it has to pump more blood as it is losing some backwards= compensate for the increased volume it needs LV Dilates more=more regurgitation and greater volume load. Results in a Vicious Circle. is a POSITIVE FEEDBACK cycle. whole time trying to maintain mean arteriole blood pressure. Until eventually it can no longer support itself.
  17. Eventually volume load is so large on heart, cannot maintain mean arteriole blood pressure(which is vital for certain organs (e.g. kidneys))
  18. Organ systems start shutting down. Renal Failure.
  19. Continues too long that the heart cannot generate enough pressure in the aorta to keep itself alive.
  20. LV failure
49
Q

What is Oedema?

A

Fluid has been pushing into tissue, without draining away properly
results in excess watery fluid collecting in cavities or tissues of the body (e.g. alveolus )

50
Q

What happen to elderly with Oedema?

A

some people who have hearts which aren’t as efficient as they should be, get Oedema in their lower limbs. Feet and Legs swell up.

51
Q

What happens when you have Oedema in the lungs?

A

requires more muscular work

52
Q

What is Dyspnoea?

A

discomfort during breathing consciousness of laboured breathing
wheezing
struggle to suck air in and out, as the lungs have lost compliance
(in this case due to Oedema)

53
Q

What is a Vicious circle?

A

What happen when you have a viral infection causing cardiomyopathy
IF cardiomyopathy (diseased lung) has stemmed from a Viral infection, Cardiac muscle fibres lengthened= LV dilated+ fibrous ring stretch= leaky valve= mitral regurgitation = V work harder= develops volume load on LV, as it has to pump more blood as it is losing some backwards= compensate for the increased volume it needs LV Dilates more=more regurgitation and greater volume load. Results in a Vicious Circle.
a POSTIVE FEEDBACK cycle
whole time trying to maintain the mean arteriole blood pressure. Reaching a point where it can no longer support itself.

54
Q

What does the kidneys require?

A

Extremely reliant on the mean arteriole blood pressure

55
Q

What is normal feedback?

A

mostly negative feedback

vs viscous cycle being positive feedback cycle, which spirals out of control

56
Q

What is treatment of cardiomyopathy?

A

Place an artificial valve into heart

half valve now St Judes valves

MedSci142 (20 decks)

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