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Yr 5 - Paeds > Revision - Foetal Circulation > Flashcards

Revision - Foetal Circulation Flashcards

1
Q

What does the ductus venosus connect?

A

Umbilical vein & inferior vena cava

Allows blood to bypass the liver

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2
Q

What is required to keep the ductus arteriosus open?

A

Prostaglandins

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3
Q

After birth, what happens to the ductus venosus?

A

Immediately after birth the ductus venosus stops functioning because the umbilical cord is clamped and there is no flow in the umbilical veins.

Becomes ligamentum venosum.

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4
Q

What is the cardiac output in adults?

A

Approx 5L/min

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5
Q

Describe foetal circulation at the liver

A

1) Oxygenated blood from the placenta travels via the umbilical vein, which branches into the L and R umbilical veins at the liver.

2) The R umbilical vein provides oxygenated blood to the liver via the portal vein, whilst the L umbilical vein branches into the ductus venosus, which bypasses the liver to carry oxygenated blood directly into the IVC

3) A mix of oxygenated (from ductus venosus) and deoxygenated (from liver and the rest of the body) blood then enters the right atrium via the IVC, also mixing with the SVC.

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6
Q

Which vessel provides oxygenated blood to the liver in foetal circulation?

A

R umbilical vein

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7
Q

Which vessel branches into the ductus venosus in fetal circulation?

A

L umbilical vein

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8
Q

What do the umbilical arteries arise from?

A

1) The aorta bifurcates into the right and left common iliac arteries.

2) These split further into the internal and external iliac arteries.

3) Each of the internal iliac arteries give rise to an umbilical artery, which travel alongside the umbilical vein to bring deoxygenated blood back to the placenta.

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9
Q

what do the umbilical vessels become after birth?

A

umbilical vein –> round ligament of liver

umbilical artery –> superior vesical arteries

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10
Q

Does a murmur becoming louder on standing indicate an innocent murmur or not?

A

No - requires more investigations.

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11
Q

What are the 3 differentials of a pansystolic murmur?

A

1) Tricuspid regurgitation

2) Mitral regurgitation

3) VSD

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12
Q

Where would a pansystolic murmur caused by mitral regurgitation be heard loudest?

A

At the mitral area (fifth intercostal space, mid-clavicular line).

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13
Q

Where would a pansystolic murmur caused by tricuspid regurgitation be heard loudest?

A

At the tricuspid area (fifth intercostal space, left sternal border).

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14
Q

Where would a pansystolic murmur caused by a ventricular septal defect be heard loudest?

A

Left lower sternal border

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15
Q

What are the 3 differentials for an ejection systolic murmur?

A

1) Aortic stenosis

2) Pulmonary stenosis

3) HOCM

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16
Q

Where would an ejection systolic murmur caused by hypertrophic obstructive cardiomyopathy be heard loudest?

A

4th intercostal space at left sternal border

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17
Q

What is splitting of the 2nd heart sound?

A

When pulmonary valve closes after aortic valve

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18
Q

When can splitting of the 2nd heart sound be normal?

A

if it varies with inspiration & expiration

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19
Q

What does a ‘fixed split’ second heart sound mean?

A

The split does NOT change with inspiration and expiration.

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20
Q

What heart condition can cause a fixed splitting of 2nd heart sound?

A

ASD

Blood is flowing from the LA into the RA across the ASD, increasing the volume of blood that the RV has to empty before the pulmonary valve can close. This doesn’t vary with respiration.

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21
Q

What murmur can be heard in ASD?

A

A mid-systolic, crescendo-decrescendo murmur, with a fixed split second heart sound.

Heard at upper left sternal border.

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22
Q

What type of murmur can a patent ductus arteriosus cause?

A

A small patent ductus arteriosus may not cause any abnormal heart sounds.

More significant PDAs cause a normal first heart sound with a continuous crescendo-decrescendo “machinery” murmur that may continue during the second heart sound, making the second heart sound difficult to hear.

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23
Q

Why may the murmur in a PDA be difficult to hear?

A

As the murmur may continue during the second heart sound, making the second heart sound difficult to hear.

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24
Q

What does the murmur in Tetralogy of Fallot arises from?

A

Pulmonary stenosis

Ejection systolic murmur heard loudest at the pulmonary area (second intercostal space, left sternal border).

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25
Q

What shunt is seen in cyanotic heart disease?

A

R -> L shunt

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26
Q

What are 4 heart defects that can cause a right-to-left shunt, and therefore cyanotic heart disease?

A

1) ASD

2) VSD

3) TGA

3) Patent ductus arteriosus (PDA)

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27
Q

Why are patients with a VSD, ASD or PDA usually not cyanotic?

A

This is because the pressure in the left side of the heart is much greater than the right side, and blood will flow from the area of high pressure to the area of low pressure.

This prevents a right-to-left shunt.

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28
Q

When will patients with VSD, ASD or PDA be cyanotic?

A

If the pulmonary pressure increases beyond the systemic pressure blood will start to flow from right-to-left across the defect, causing cyanosis.

This is called Eisenmenger syndrome.

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29
Q

What is Eisenmenger syndrome?

A

Reversal of a L to R shunt due to pulmonary HTN.

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30
Q

What 3 defects is Eisenmenger’s syndrome associated with?

A

1) VSD

2) ASD

3) PDA

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31
Q

What are the 2 types of innocent ejection murmurs heard in children?

A

1) Venous hums

2) Stills murmur

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32
Q

What is venous hums murmur caused by?

A

Due to the turbulent blood flow in the great veins returning to the heart.

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33
Q

How is a venous hums murmur heard?

A

Heard as a continuous blowing noise heard just below the clavicles.

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34
Q

O2 saturation in RA in ASD?

A

Causes increased O2 saturation in RA, RV & pulmonary artery.

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35
Q

Why does cyanosis in PDA (that has transformed into Eisenmenger’s) only affect lower limbs?

A

Arterial branches to upper extremeties upstream from PDA (‘differential cyanosis’)

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36
Q

Mx of PDA in neonates?

A

Indomethacin (NSAID that inhibits prostaglandin E2)

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37
Q

What is a key risk factor for PDA?

A

Prematurity

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38
Q

Management of a PDA?

A

1) Patients are typically monitored until 1 year of age using echocardiograms.

2) After 1 year of age it is highly unlikely that the PDA will close spontaneously and trans-catheter or surgical closure can be performed.

3) Symptomatic patient or those with evidence of heart failure as a result of PDA are treated earlier.

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39
Q

After what age is a PDA unloikely to close spontaneously (and trans-catheter or surgical closure can be performed?)?

A

1 year of age

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40
Q

What is there a connection between in PDA?

A

Pulmonary artery & descending aorta

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41
Q

Risk factors for PDA?

A

1) Prematurity

2) Babies born at high altitude

3) Maternal rubella infection in 1st trimester

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42
Q

Potential examination findings in PDA?

A

1) left subclavicular thrill

2) continuous ‘machinery’ murmur

3) wide pulse pressure

4) large volume, bounding, collapsing pulse

5) heaving apex beat (RVH)

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43
Q

Describe the murmur in PDA

A

A continuous crescendo-decrescendo “machinery” murmur that may continue during the second heart sound, making the second heart sound difficult to hear.

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44
Q

What is the most likely congenital heart defect to be found in adulthood?

A

ASD

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45
Q

What is the most common type of ASD?

A

Ostium secundum defect

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46
Q

What size ASD should spontaneously close?

A

<5mm should close spontaneously within 12m of birth

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47
Q

What size ASD is typically managed surgically?

A

> 10mm (1cm)

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48
Q

Who is surgical closure of ASD NOT recommended in?

A

Not recommended in patients where pulmonary HTN is present (mean pulmonary pressure of 30mmHg), as this can induce RV failure if the ASD is closed up.

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49
Q

Define pulmonary HTN

A

Mean pulmonary pressure of 30mmHg

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50
Q

Complications of untreated large ASDs?

A

1) TIA/stroke

2) Arrhythmias e.g. AF (due to atrial stretch)

3) Pulmonary HTN & RHF

4) Eisenmenger’s syndrome

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51
Q

What congenital heart defect is Holt–Oram syndrome associated with?

A

Ostium secundum

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52
Q

What is Holt-Oram syndrome?

A

The characteristic hand malformation is digitalisation of a triphalangeal thumb so that the thumb is attached in the same plane as other fingers.

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53
Q

What are the three underlying lesions that can result in Eisenmenger syndrome?

A

1) ASD

2) VSD

3) PDA

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54
Q

How does cyanosis lead to an increased risk of clots?

A

1) bone marrow responds to low O2 by making more RBCs and Hb

2) leads to polycythaemia

3) high conc of RBCs & Hb makes blood more viscous

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55
Q

Examination findings in pulmonary HTN?

A

1) RV heave

2) Loud P2

3) Raised JVP

4) Peripheral oedema

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56
Q

Describe the murmur heard in the following septal defects:

1) ASD
2) VSD
3) Patent ductus arteriosus

A

1) mid-systolic, crescendo-decrescendo murmur loudest at the upper left sternal border

2) pan-systolic murmur loudest at the left lower sternal border

3) continuous crescendo-decrescendo “machinery” murmur

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57
Q

What exam findings may be seen in Eisenmenger syndrome that are related to the right to left shunt and chronic hypoxia?

A

1) cyanosis
2) clubbing
3) dyspnoea
4) plethoric complexion (a red complexion related to polycythaemia)

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58
Q

When does it become medically impossible to reverse Eisenmenger syndrome?

A

Once the pulmonary pressure is high enough to cause the syndrome, it is not possible to medically reverse the condition.

Only definitive treatment is heart-lung transplantation.

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59
Q

What medicine can be used in the management of pulmonary HTN?

A

Sildenafil (PDE-5 inhibitor)

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60
Q

Treatment of polycythaemia?

A

Venesection

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61
Q

What infection in the 1st trimester can lead to PDA in the neonate?

A

Maternal rubella infection

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62
Q

What 2 genetic conditions are VSDs associated with?

A

1) Turner’s syndrome
2) Down’s syndrome

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63
Q

Why are VSDs less common in adults?

A

As up to 50% of VSDs spontaneously close

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64
Q

O2 saturation in heart in VSD?

A

Increased O2 saturation in RV & pulmonary artery

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65
Q

What murmur is heard in VSD?

A

Pansystolic mumur, more prominently heard at the left lower sternal border in the third and fourth intercostal spaces.

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66
Q

What are the 3 causes of a pansystolic murmur?

A

1) VSD

2) Mitral regurgitation

3) Tricuspid regurgitation

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67
Q

Where is thrill felt in VSD?

A

A systolic thrill of maximal intensity in the lower left sternal border would be expected.

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68
Q

What is contraindicated in pulmonary HTN?

A

Pregnancy !

Mortality risk of up to 50%

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69
Q

How can the risk of infective endocarditis be reduced in patients with VSD?

A
  • Good oral hygiene
  • Avoid non-medical procedures, such as piercings and tattoos.
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70
Q

Medical management options in VSD?

A

1) Diuretics - reduce pulmonary HTN

2) ACEi - reduce L to R shunt

3) Digoxin - treat congestive cardiac failure

71
Q

Which diuretics are typically given in VSD?

A

Furosemide & spironolactone can be added to minimise potassium loss.

72
Q

Is there need for exercise restriction in VSD?

A

Usually no

73
Q

When is the surgical closure of a VSD indicated?

A

When there is a Qp/Qs (pulmonary-to-systemic blood flow ratio) of 2.0 or more.

74
Q

What condition do AVSDs have a strong association with?

A

Down’s syndrome

75
Q

How does AVSD affect the left ventricular outflow tract (LVOT)?

A

The structural changes lead to an increased distance between the aorta and the apex of the heart.

This results in an elongation of LVOT and abnormal position of the aortic valve which is displaced anterosuperior rather than being wedged between right and left AV valves.

76
Q

What anatomical change is seen on an ECHO in AVSD?

A

“goose neck” deformity - due to elongation of LVOT

77
Q

When do symptoms in COMPLETE AVSD present?

A

Virtually all patients with complete AVSD have symptoms by 1 year of age.

78
Q

What are Harrison grooves?

A

horizontal depression along lower border of chest at diaphragm insertion site due to chronic tachypnoea.

e.g. in AVSD

79
Q

What causes a palpable apical thrill in AVSD?

A

May result due to regurgitation of the atrioventricular valve.

80
Q

Auscultation findings in complete AVSD?

A

1) An accentuated S1

2) Loud pulmonary component of S2

3) Ejection-systolic murmur

4) Mid-diastolic murmur

5) Pansystolic murmur

81
Q

What causes the ejection systolic murmur in AVSD?

A

Due to increased blood flow through a normal pulmonary valve

82
Q

What causes the mid diastolic murmur in AVSD?

A

Due to the increased flow across the common atrioventricular valve.

83
Q

What causes the pansystolic murmur in AVSD?

A

Heard if left atrioventricular valve regurgitation is present.

84
Q

What investigation should be done in AVSD due to the strong association with Down syndrome?

A

Karyotyping

85
Q

When do infants with complete AVSD develop heart failure?

A

Within first few months of life.

86
Q

Location of narrowing in coarctation of aorta in infants?

A

Narrowing is AFTER the aortic arch but BEFORE the ductus arteriosus i.e. preductal coarctation

87
Q

Describe ductus arteriosus in coarctation of aorta (in infants)

A

Typically patent (PDA)

88
Q

Result of patent PDA in coarctation of aorta?

A

There is increased pressure proximal to the coarctation, but decreased pressure after the coarctation.

As the PDA is found just after the coarctation, there is less pressure here. Therefore, blood will travel from the R side, through the PDA, causing deoxygenated blood to be carried to the body.

Result –> cyanosis of lower extremities (often present at birth)

89
Q

What syndrome is coarctation of the aorta associated with?

A

Turner’s syndrome

90
Q

In adults, where is coarctation of the aorta located?

A

Just before the ligmanetum arteriosum

91
Q

Complications of coarctation of aorta in adults?

A

1) HIGHER pressure proximal to coarctation –> increased BP in upper exrtemities & head:
- increased risk of berry aneurysms
- aortic dilatation (risk of aortic dissection)

2) LOWER pressure distal to coarctation –> decreased BP in lower extremities & head:
- reduced pulses
- claudication
- HTN (due to activation of RAAS due to hypoperfusion of kidneys)

3) Rib notching (typically ribs 3-9)

4) HTN

92
Q

Mx of aortic coarctation?

A

1) Balloon dilation

2) Surgical removal of coarctation

93
Q

Is coarctation of the aorta more common in males or females?

A

Males (despite association with Turner’s)

94
Q

Often, what is the only indication of coarctation of the aorta in neonates?

A

Weak femoral pulses

Radiofemoral delay

95
Q

How will coarctation of the aorta affect BP?

A

Perform a four limb BP:

1) High BP in limbs supplied from arteries that come before the narrowing

2) Lower BP in limbs that come after the narrowing

96
Q

What additional 3 signs of coarctation of aorta may develop over time?

A

1) Left ventricular heave due to left ventricular hypertrophy

2) Underdeveloped left arm where there is reduced flow to the left subclavian artery

3) Underdevelopment of the legs

97
Q

What key sign is seen in adults in coarctation of the aorta?

A

HTN

98
Q

What is given in cases of critical coarctation that require emergency surgery?

A

Prostaglandin E (keeps DA open whilst waiting for surgery)

99
Q

What is the hallmark of TGA?

A

Ventriculoarterial discordance

This is when the aorta arises from the morphologic right ventricle and the pulmonary artery arises from the morphologic left ventricle

100
Q

In the majority of patients (60%) with TGA, where is the aorta in relation to the pulmonary artery?

What is this called?

A

The aorta is anterior and to the right of the pulmonary artery (dextro-transposition of the great arteries [d-TGA]).

101
Q

What are the 2 possible classifications of TGA?

A

1) Dextro-transposition of the great arteries [d-TGA]) –> the aorta is anterior and to the right of the pulmonary artery

2) Levo-transposition of the great arteries [l-TGA]) –> the aorta may be anterior and to the left of the pulmonary artery

102
Q

What is the most common cause of cyanosis in the new born?

A

TGA

103
Q

Describe what happens in dextro-TGA

A

The pulmonary and systemic circulation run in parallel, causing oxygenated blood to recirculate only in the pulmonary circulation and deoxygenated systemic blood to bypass the lungs.

This results in cyanosis unless there is mixing of oxygenated blood and deoxygenated blood.

104
Q

What are 3 common anatomic sites for mixing of oxygenated and deoxygenated blood in TGA that allows life to be sustained?

A

1) PDA

2) VSD

3) Patent foramen ovale or ASD

105
Q

What happens in levo-TGA [also called as CC-TGA]?

A

The ventricles have switched places as opposed to the arteries.

This is acyanotic as deoxygenated blood can return from the systemic circulation and enter the pulmonary circulation to be oxygenated before entering the systemic circulation again.

However, the right ventricle and tricuspid valve is not accustomed to the higher pressures of the left side of the heart. There is hypertrophy over time, which can result in tricuspid regurgitation and heart failure.

106
Q

What are the maternal risk factors for TGA?

A

1) Age >40 y/o

2) Maternal diabetes

3) Rubella

4) Poor nutrition

5) Alcohol consumption

107
Q

Presentation of TGA?

A

1) Cyanosis: at birth or within 24 hours (if no mixing at the atrial level)

2) Mild cyanosis (particularly when crying) might be evident)

3) Signs of congestive heart failure may appear over first 3-6 weeks:
- tachypnoea
- sweating
- poor feeding
- failure to gain weight

108
Q

Management of TGA?

A

1) Emergency prostaglandin E1 infusion –> to keep the ductus arteriosus patent as a temporary solution that allows mixing of blood

2) Correct metabolic acidosis

3) Emergency atrial balloon septostomy to allow for mixing

4) Definitive –> surgical correction

109
Q

What is a typical CXR finding in TGA?

A

“Egg on a string” due to potentially narrowed upper mediastinum; cardiomegaly and increased pulmonary vascular markings

110
Q

What is the most ommon cyanotic congenital heart disease (CHD) presenting AFTER the neonatal period?

A

ToF

111
Q

What are the 4 defects seen in TOF?

A

1) Pulmonary stenosis

2) VSD

3) Overriding aorta

4) RVH (as a result of pulmonary stenosis)

112
Q

What genetic conditions can TOF be associated with?

(2)

A

1) Down’s syndrome

2) DiGeorge syndrome

3) Chromosome 22 deletions

113
Q

What is DiGeorge syndrome?

A

Caused by a microdeletion on the long arm of chromosome 22. It is also known as 22q11.2 deletion syndrome.

Autosomal dominant.

114
Q

What are the salient features of DiGeorge syndrome?

Mneumonic: CATCH-22

A

C - Cardiac abnormalities (commonly Tetralogy of Fallot)

A - Abnormal facies (cleft palate, hypertelorism and short philtrum)

T - Thymic aplasia/hypoplasia

C - Cleft palate

H - Hypocalcaemia/hypoparathyroidism

115
Q

What cardiac abnormality is most commonly seen in DiGeorge syndrome?

A

ToF

116
Q

What happens after birth in TOF?

A

Normally –> the ductus arteriosus and foramen ovale close as they are not required.

In TOF:

1) The VSD allows the mixing of oxygenated and deoxygenated blood.

2) This means deoxygenated blood enters the aorta and is pumped to the rest of the body –> cyanosis.

3) Overriding aorta means that the aortic valve is placed further to the right than normal, above the VSD. The aorta is also enlarged.

4) When the right ventricle contracts and pumps blood upwards, the aorta is in the direction of travel of that blood –> more deoxygenated blood enters the aorta from the right side of the heart.

5) Pulmonary stenosis means there is greater resistance to the flow of blood from the right ventricle into the pulmonary artery.

6) Instead of deoxygenated blood flowing through the pulmonary artery to the lungs, blood is pushed through the VSD into the aorta.

7) The pulmonary stenosis along with the overriding aorta causes deoxygenated blood to be shunted from the right to the left side of the heart causing cyanosis.

8) The right ventricle is pumping blood into the pulmonary artery under great resistance due to pulmonary stenosis, and due to pressures from the left ventricle being directly transmitted to the right ventricle because of the open VSD –> right ventricular hypertrophy.

117
Q

What is the impact of the VSD in TOF?

A

This allows the mixing of oxygenated and deoxygenated blood so deoxygenated blood enters the aorta and is pumped to the rest of the body –> cyanosis.

118
Q

What is the impact of the overriding aorta in TOF?

A

This means that the aortic valve is placed further to the right than normal, above the VSD.

The aorta is also enlarged.

When the right ventricle contracts and pumps blood upwards, the aorta is in the direction of travel of that blood. Therefore, more deoxygenated blood enters the aorta from the right side of the heart.

119
Q

What is the impact of the pulmonary stenosis in TOF?

A

This means there is greater resistance to the flow of blood from the right ventricle into the pulmonary artery.

The pulmonary stenosis along with the overriding aorta causes deoxygenated blood to be shunted from the right to the left side of the heart causing cyanosis.

120
Q

What is the degree of cyanosis in TOF related to?

A

The severity of pulmonary stenosis

121
Q

Risk factors for ToF?

A

1) 1st-degree family history of congenital heart disease

2) A parent with Tetralogy of Fallot

3) A parent with DiGeorge syndrome

4) Foetal exposure to teratogens in utero –> alcohol, warfarin and trimethadione

5) Poorly controlled maternal diabetes

6) Maternal intake of retinoic acid

7) Congenital Rubella infection

8) Increased maternal age (over 40 years old)

122
Q

How may right ventricular hypertrophy be seen on a CXR?

A

As the ‘boot’ sign.

123
Q

What causes aortic dilatation in ToF?

A

Aortic dilatation is caused by an increase in blood flow through the aorta as it receives blood from both ventricles via the VSD.

124
Q

Clinical features will vary depending on the subtype of TOF.

What are the 3 major subtypes of ToF?

A

1) TOF with a milder form of pulmonary stenosis

2) TOF with pulmonary atresia

3) TOF with absent pulmonary valve

125
Q

Clinical general exam findings in ToF?

A

1) Central cyanosis

2) Clubbing

3) Respiratory distress

4) Poor feeding & poor weight gain

5) ‘Tet spells’

The level of stenosis will determine when and how they present.

126
Q

How are many cases of ToF identified?

A

Antenatal screening

127
Q

What murmur is heard in ToF?

A

Ejection systolic murmur heard loudest in the pulmonary area (second intercostal space, left sternal border)

Due to pulmonary stenosis

128
Q

How many ToF present on an ECG?

A

TOF may present with right axis deviation and right ventricular hypertrophy

129
Q

What may a CXR show in ToF?

A

1) A boot-shaped heart (due to RVH)

2) Reduced pulmonary vascular markings (due to reduced pulmonary blood flow)

130
Q

What causes the ejection click in TOF?

A

Due to the closure of the dilated aorta

131
Q

What will auscultation of the heart during a tet spell reveal?

A

There will be a reduced/absent murmur due to decreased pulmonary blood flow and a tightly ‘shut’ infundibulum.

132
Q

How will children with ToF typically manage a tet spell themselves?

A

By squatting or bringing their knees to their chest.

Squatting increases the systemic vascular resistance which pushes blood into the pulmonary vessels.

133
Q

What can management of a tet spell include?

A

1) Position the child with their knees at their chest

2) Oxygen

3) Morphine: decreases respiratory drive

4) IV fluids: increase pre-load which increases the volume of blood which flows into the pulmonary vessels

5) Beta-blockers (propranolol): relaxes the right ventricle infundibulum and improves the flow of blood to the pulmonary vessels

6) Phenylephrine infusion: increases systemic vascular resistance

7) Emergency ventricular outflow tract stent or BT shunt

8) Sodium bicarbonate if there is metabolic acidosis

134
Q

Role of morphine in a tet spell?

A

Decreases respiratory drive, resulting in more effective breathing.

135
Q

Role of propanolol in a tet spell?

A

Relaxes the right ventricle infundibulum and improves the flow of blood to the pulmonary vessels

136
Q

Role of IV fluids in a tet spell?

A

Can increase pre-load, increasing the volume of blood flowing to the pulmonary vessels.

137
Q

When does surgical intervention of ToF typically occur?

A

Surgical intervention typically occurs within the first year of life.

Some patients receive a bridging procedure before complete repair of the Tetralogy of Fallot.

138
Q

Medical management options in ToF?

A

1) Squatting

2) Prostaglandin (PG) infusion

3) Beta blockers

4) Morphine

5) Saline 0.9% bolus

139
Q

What is a Blalock-Taussig (BT) shunt?

A

This can be placed as a form of intermediate management in ToF until a complete repair can be conducted.

It allows babies to grow so they are better suited for their complete repair.

This mimics a PDA

140
Q

What age does surgical repair of ToF typically occur?

A

Between 3 months - 4 years.

141
Q

What does a loud P2 indicate?

A

Pulmonary HTN

142
Q

When should surgery be performed in a large VSD?

A

<12m of age (to prevent persistent pulmonary hypertension of the newborn (PPHN))

143
Q

What may be seen in ASDs?

A

recurrent chest infections

144
Q

What may an ECG show in ASD?

A

Incomplete RBBB

145
Q

What size ASD typically spontaneously close?

A

<7-8mm

146
Q

When do symptoms of PDA typically present?

A

3-5 days after birth when the duct begins to close

147
Q

Where is the murmur in PDA best heard?

A

Just below L clavicle

148
Q

Who is indomethacin not effective in in closing a PDA?

A

Babies born at term

149
Q

Location of murmur in coarctation of aorta?

A

At the back between the scapulae

150
Q

Medical management of coarctation of the aorta?

A

1) Continuous IV infusion of prostaglandin E1 to keep the ductus arteriosus open

2) Dopamine or Dobutamine to improve contractility in those with heart failure

3) Supportive care to correct metabolic acidosis, hypoglycemia, respiratory failure, and anaemia that may contribute to or be a consequence of heart failure

151
Q

When does ToF typically present?

A

During the neonatal period when the patent ductus arteriosus begins to close (day 3-5)

152
Q

What is murmur caused by in ToF?

A

Pulmonary stenosis (not VSD)

153
Q

Management of ToF in neonates with severe cyanosis?

A

Prostaglandin infusion to maintain patency of ductus and pulmonary flow until the time of surgical repair.

154
Q

When does TGA typically present?

A

During neonatal period when the patent ductus arteriosus begins to close (day 3-5)

155
Q

What is a Still’s murmur?

A

A soft vibratory murmur heard over the lower-left sternal border most frequently in childhood when there is normal blood flow and no cardiac lesion.

156
Q

What is a venous hum?

A

Continuous murmur heard loudest over the clavicles due to venous return from the head and neck, and this varies with position.

157
Q

What murmur may be heard in Turner’s? Why?

A

Bicuspid aortic valve –> crescendo-decrescendo murmur heard best in URSB

Radiates to carotid

158
Q

Describe pulse features in PDA

A
  • large volume
  • bounding
  • collapsing
159
Q

What is the most common heart lesion associated with Duchenne muscular dystrophy?

A

Dilated cardiomyopathy

160
Q

What does functional tricuspid regurgitation often occur 2ary to?

A

Pulmonary HTN (e.g. due to COPD)

This causes a pansystolic murmur in the LLSB

161
Q

Give 3 causes of tricuspid regurg

A

1) Pulmonary HTN

2) Mitral valve stenosis & regurg

3) Pulmonary thromboembolism.

162
Q

What is the most cardiac defect associated with Turner’s?

A

Bicuspid aortic valve (more common than coarctation of the aorta)

163
Q

A patient develops acute heart failure 5 days after a myocardial infarction. A new pan-systolic murmur is noted on examination.

What is the complication?

A

VSD

164
Q

When is the ejection systolic murmur in ASD heard best?

A

During inspiration

165
Q

What condition occasionally be associated with a bisferiens pulse?

A

HOCM

166
Q

What is alprostadil?

A

Prostaglandin

167
Q

3 options for treating congenital aortic stenosis?

A

1) Percutaneous balloon aortic valvoplasty
2) Surgical aortic valvotomy
3) Valve replacement

168
Q

How many leaflets does the pulmonary valve usually consist of?

A

3 leaflets

169
Q

Congenital pulmonary valve stenosis often occurs without any associations.

What 4 conditions can it be associated with?

A

1) ToF

2) Noonan syndrome

3) Williams syndrome

4) Congenital rubella syndrome

170
Q

What is the treatment of choice of symptomatic pulmonary stenosis?

A

Balloon valvuloplasty via a venous catheter.

171
Q

What is Ebstein’s anomaly?

A

Ebstein’s anomaly is a congenital heart defect where the tricuspid valve is set lower in the right side of the heart (towards the apex), causing a bigger right atrium and a smaller right ventricle.

172
Q

What 2 conditions is Ebstein’s anomaly associated with?

A

1) ASD or patent foramen ovale (PFO) (80% patients) –> resulting in a shunt between the right and left atria

2) Wolff-Parkinson-White syndrome

173
Q

Exposure to what medication in utero can cause Ebstein’s anomaly?

A

Lithium

174
Q
A

Yr 5 - Paeds (21 decks)

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