Valves, malformations & endocarditis

Question 1

what are the right valves

Answer 1

pulmonary

tricuspid

Question 2

what are the left valves

Answer 2

aortic

mitral/bicuspid

Question 3

why are the left valves more likely to fail

Answer 3

they are at the highest pressure.

Question 4

what are the two ways valves can fail

Answer 4

stenosis

incompetence

Question 5

what is stenosis

Answer 5

the valve cannot open properly and so doesn’t allow blood through properly

Question 6

what is incompetence

Answer 6

when the valve cannot close properly

Question 7

what does a valve problem lead to

Answer 7

increase the risk that the patient will develop heart failure therefore when someone has a valve that does not work properly they must be replaced with a prosthetic one before permanent damage to the heart occurs thus early treatment is important!

Question 8

how can an MI lead to valve problems

Answer 8

Heart valves are little cusplets of collagen and they are attached to the papillary muscles through tendons called chordinae tendinea
The papillary muscles keep the valves under tension and keep it shut. If you have an MI then this can cause damage to the papillary muscles and end up with valve function problems

Question 9

if the mitral valve does not open properly what does it lead to

Answer 9

it causes an increase in pressure in the atrium and a lack of blood in the ventricle causing a decreased cardiac output and an increase in pressure in the pulmonary system.

Question 10

what happens in rheumatic heart disease

Answer 10

the body forms an antibody against bacteria, but it also targets the tissue of the heart valve due to having the same protein structure which causes damage to the valves.

Question 11

what can cause valve disease

Answer 11

congenital abnormality
myocardial infarction
rheumatic fever
dilation of the aortic root

Question 12

how does congenital abnormality lead to valve disease

Answer 12

o Formed incorrectly during development
o Cannot do the job you want it to do
o Bicuspid aortic valve instead of normal tricuspid aortic valve

Question 13

how does MI cause valve disease

Answer 13

o Papillary muscle rupture

Question 14

how does rheumatic fever lead to valve disease

Answer 14

o Immunological reaction to streptococci

Question 15

how does dilation of the aortic root lead to valve disease

Answer 15

o If you dilate the aortic root then it is stretched and the valve gets pulled apart so cannot do their job – issue here is not to do with the valve but with the aorta
o Syphilis
o Aneurysm formation

Question 16

how can you investigate valve disease

Answer 16

ultrasound of the heart
dye allows for better assessment
can see different directions of blood
if working properly should be moving only in one direction

Question 17

what is the most common valve replacement

Answer 17

Valve replacements are generally mechanical, they are made in a workshop and will essentially be made of metal.

Question 18

what is the advantage of mechanical valve replacement

Answer 18

long lasting

Question 19

what is the disadvantage of mechanical valve replacement

Answer 19

lifetime of anticoagulants

Question 20

why do pig valves not attract clots

Answer 20

they contain the normal collagen leaflets

Question 21

who are pig valves used for

Answer 21

those in extremes oof life

Question 22

what do those with valve replacements have risk of

Answer 22

endocarditis

Question 23

what is a congenital heart defect

Answer 23

These happen as the embryo is forming

It is the failure of the fusion of the heart

Question 24

what is an ASD

Answer 24

When there is overfusion of the atria there is a hole from the left to the right side of the atria however the atria is a low pressure system and the differences in pressures is not great so for many cases the effect is not noticeable

Question 25

what are VSD

Answer 25

in the ventricles and these are a high pressure system and there is a difference between the left and right. When the left ventricle contracts some of the blood goes through to the right ventricle increasing the workload of the right side which can lead to right sided heart failure. You need to repair most VSDs

Question 26

what is ductus arteriosus

Answer 26

a bypass between pulmonary circulation and systemic circulation because an unborn child does not need to use their lungs

Question 27

what is patent ductus arteriosus

Answer 27

failure of closure of arteriosus

Question 28

what are congenital heart defects

Answer 28

ASD VSD patent ductus arteirosus great vessel malformation

Question 29

what is cyanosis

Answer 29

exists when there is 5g/dl or more of deoxygenated Hb in the blood makes it difficult to get enough oxygen to the tissues and you go blue if you have it

Question 30

what is central cyanosis due to

Answer 30

due to congenital heart disease – people with this are blue all over, even in tissues that are usually pink.

Question 31

what is peripheral cyanosis

Answer 31

Peripheral cyanosis is due to the cold environment

Question 32

what is finger clubbing

Answer 32

Much not understanding of it but causes swelling in the terminal tissues of the fingers – due to chronically low blood levels of oxygen

Question 33

what happens in VSD

Answer 33

Portion of the blood in the left ventricle is going to the right ventricle and it going back through the pulmonary artery into the lungs. The left ventricle is having to work harder to maintain the CO and the right ventricle is having to work harder to deal with the increased volume

Question 34

what happens in correction of the aorta

Answer 34

When the baby is born a deep breath is taken causing a pressure difference in the lungs meaning that it is better to go through the pulmonary artery than the aorta and as oxygen level builds up and the oxygen tension goes up the ductus shuts. Sometimes the closing goes onto the aorta and results in a narrowed aorta making it difficult to carry blood through the aorta.

Question 35

what happens in patent ductus arteriosus

Answer 35

If it remains open it goes through the aorta and back to the lungs and it can lead to heart failure.

Question 36

what are those with congenital abnormalities more at risk of

Answer 36

endocarditis – guidance from a cardiologist is required.

Question 37

What is endocarditis

Answer 37

infection of the endocardium | usually on the valves

Question 38

How does infective endocarditis happen

Answer 38

microbial colonisation of thrombi on endocardial surface abnormalities

Question 39

What are predisposing factors for endocarditis

Answer 39

rheumatic fever less common now | prosthetic valves more common now