Principles of congential heart disease

Question 1

valves are

Answer 1

passive blockers of blood flow

Question 2

principles of congenital heart disease

Answer 2

fetal circulation
development of heart
determinants of flow
cyanosis
adaptations to abnormal flow

Question 3

fetal circulation

Answer 3

• one umbilical vein carrying oxygenated blood and 2 umbilical arteries returning de-oxygenated blood
• flow into heart right to left

Question 4

what does the PDA allow for?

Answer 4

some blood flow to lungs

Question 5

what closes the ASD in fetal circulation?

Answer 5

natural valve mechanism closes ASD after birth with increases pressures on left

Question 6

tardive cyanosis

Answer 6

when de-oxygenated blood is on the left side of heart because of high pressure on right side of heart-> cause cyanosis

Question 7

when should congenital heart diseases be fixed before?

Answer 7

do it before get irreversible pulmonary HTN

Question 8

things that cause early cyanosis (flow from right to left)

Answer 8

all start with a T

• tricuspid atresia
• tetralogy of fallot
• truncus ateriosus
• transposition of the great arteries

Question 9

development of heart

Answer 9

starts as tube-> requires 6 important developmental steps

Question 10

separation of right heart from left heart: natural structures

Answer 10

septum primum, secundum

ventricular septum

Question 11

abnormalities

Answer 11

ASD

VSD (is less than 1cm, not clinical)

Question 12

most common abnormality

Answer 12

VSD

Question 13

separation of atria from ventricles

Answer 13

tricuspid valve

mitral valve

Question 14

abnormalities of separation of atria from ventricles

Answer 14

tricuspid atresia/stenosis

-atresia meaning lack of development

Question 15

division of pulmonary and arterial outflow

Answer 15

pulmonic valve

aortic valve

Question 16

abnormalities of division of pulmonary and arterial outflow

Answer 16

pulmonic stenosis
aortic stenosis
truncus arteriosus
transposition of great arteries

Question 17

development of junction between valves and ventricular wall abnormalities

Answer 17

tetralogy of fallot

endocardial cushions defects (seen in down syndrome)

Question 18

closing of ductus arteriosus normally

Answer 18

closes when PG no longer synthesized-> treat with PGE to keep it open

Question 19

what is given to close persistent PDA?

Answer 19

aspirin

Question 20

cyanosis involved with PDA?

Answer 20

involves toes, not fingers

Question 21

abnormalities of aortic arch

Answer 21

-coarctation of aorta
infantile pre-DA: not enough blood to upper body
adult form post-DA: not enough blood to lower part of body

Question 22

what determines flow

Answer 22

pressure

Question 23

flow before birth?

Answer 23

right to left

Question 24

flow after birth?

Answer 24

left to right

Question 25

what does flow from right to left result in?

Answer 25

cyanosis | -only occur if there is a non-valve opening and pressures on the right are greater than pressures on the left

Question 26

what are some potential openings that can cause cyanosis?

Answer 26

atrial septal defect VSD PDA

Question 27

what results in early cyanosis

Answer 27

flow from right to left | -mixing of blood in right and left circulations from birth, abnormalities force right to left flow

Question 28

what determines late cyanosis

Answer 28

when flow is initially from left to right, but later changes from right to left -no cyanosis early on, cyanosis after reversal-> takes years and results only after irreversible pulmonary HTN has developed

Question 29

what don't respond well to increased volume or pressures?

Answer 29

RV and pulmonary artery | -with time pulmonary artery pressures increase and flow reverse

Question 30

when are openings in fetal heart important?

Answer 30

sometimes openings must exist for baby to survive - blood can only get to lungs two ways - oxygenated blood can get to left side of heart in four ways

Question 31

what are the two ways blood gets to lungs?

Answer 31

1. thru pulmonic valve or | 2. thru a PDA

Question 32

what are the four ways oxygenated blood gets to left side of heart?

Answer 32

1. through LA 2. ASD 3. VSD 4. PDA - routes limited by flow considerations

Question 33

when is repair done with early cyanosis?

Answer 33

RIGHT AWAY

Question 34

when is repair done with late cyanosis?

Answer 34

until child is older

Question 35

when must a repair be done before?

Answer 35

pulmonary HTN

Question 36

main features of abnormalities?

Answer 36

cyanosis and exercise intolerance

Question 37

what do they clinical features of abnormalities depend on?

Answer 37

mixing of oxygenated and un-oxygenated blood

Question 38

what can result from right to left flow?

Answer 38

- emboli - infection/abscess * elements of blood can gain access to the systemic circulation and CNS without being filtered out in the lungs

Question 39

incidence of heart abnormalities

Answer 39

- 6-8/1000 live births | - higher in pre-mature births

Question 40

epidemiology

Answer 40

>90% unknown 5% chromosomal abnormalities 2-3% hereditary syndrome <1% rubella ( PDA, pulmonic valvular or arterial stenosis, aortic stenosis, tetralogy of fallot, VSD, cataracts, deafness, microcephaly) -excessive cigarette smoking, alcohol, thalidomide

Question 41

chest trauma can

Answer 41

tear ligamentum arteriosum