Paeds- VSD + ASD + PDA + TOF Flashcards
Is VSD a cyanotic or acyanotic heart defect?
a) Acyanotic
b) Cyanotic
c) Both
a) Acyanotic
Ventricular septal defect is an acyantotic heart defect, although it can progress to cyanotic if not treated
What murmur does VSD present with?
a) Continuous
b) Ejection systolic
c) Holosystolic
d) Mid systolic
c) Holosystolic
VSD can be heard throughout all of systole
What is the gold standard investigation for diagnosing VSD?
a) Chest X-ray
b) Pulse oximetry
c) ECG
d) Echocardiogram
d) Echocardiogram
An echocardiogram is the gold standard investigation for VSD, it can directly visualise size and therefore severity
What is ‘Ventricular septal defect’
- A congenital or acquired acynotic heart defect
- Defect in the inter-ventricular septum that allows shunting of blood between left and right ventricles.
What is the most common congenital heart defect?
VSD
VSD is the failure of fusion between __________ and _________ ridge
VSD is a failure of fusion between membranous and muscular ridge
Patho of VSD?
- Causes a left to right shunt because the pressure is higher in the left ventricle
- Oxygenated blood in the left ventricle is shunting to the right ventricle to re-enter the lungs
- This means that only oxygenated blood goes around the body so there is no cyanosis
What are cyanotic heart defects?
Teralogy of fallot
Transposition of the great arteries
Name the left to right shunts heart defects that are acyanotic
- Ventricular Septal Defect
- Persisent Ductus Arteriosus
- Atrial Septal Defect
Name the outflow obstruction heart defects that are acyanotic
- Pulmonary stenosis
- Aortic Stenosis
- Coarctation of aorta
What is eisenmenger syndrome?
- This can develop in babies with large VSDs where diagnosis and treatment is delayed
- Increased blood in the right ventricle causes pulmonary hypertension
- This creates higher pressures in the right ventricle and the shunt switches from left to right to right to left
- This means deoxygenated blood goes around the body and there is cyanosis
Symptoms of VSD?
• It depends on the size of the defect
• Small: Asymptomatic, normal growth. Often noticed because of as systolic murmur during routine exam.
• Moderate: Poor feeding, failure to thrive, short of breath (SOB). Symptoms noticed by 2-3 months as pulmonary vascular resistance decreases, causing an increase in left-right shunting.
• Large: Poor feeding, failure to thrive, SOB, sweaty and pale with feeds, frequent chest infections, easily fatigued and tachypnoea. Symptoms similar to congestive heart failure.
How can you present with VSD?
- Can present several ways, here are some examples:
- An infant is noted at birth to have a cardiac murmur. Examination reveals a systolic murmur at left sternal border, with no clinical evidence of heart failure.
- An infant presents with symptoms of SOB on exertion and failure to thrive. Examination reveals systolic murmur at left sternal border and signs of congestive heart failure.
Presentation of eisenmenger syndrome?
Eisenmenger syndrome: Presents with central cyanosis, may have clubbing, evidence of heart failure and a history of recurrent pulmonary infections.
Which disorder has a strong association with VSD?
To note, 1/3 of babies with Downs syndrome have a VSD- strong association
Ix of VSD?
• Pulse oximetry: To assess perfusion
• Echocardiogram: Gold standard- can visualize size, location and severity.
• CXR: To look for cardiomegaly and pulmonary oedema if severe. Can be normal with small VSDs
• ECG: Can show left or bilateral ventricular hypertrophy
Differential Diagnosis of VSD?
• Mitral regurgitation- has a similar holosystolic murmur in the same region so needs echo to differentiate
• Tricuspid regurgitation- has an increase in murmur intensity with inspiration (Carvalho’s sign)
• Atrial septal defect- murmur higher up and is mid or ejection systolic, not holosystolic
• Patent ductus arteriosus- Continuous murmur
• Tetralogy of Fallot- symptoms more severe than with VSDs
Clinical examination of VSD
- Inspection: Appear undernourished (due to fatigue in feeding), sweat on forehead
- Palpation: - Raised pulse rate - Thrill in left sternal border - Hepatomegaly (in heart failure)
- Auscultation: - Holosystolic (aka pansystolic) blowing murmur in left parasternal region. - The loudness of a murmur is inversely proportionate to the size of the defect ie the bigger the defect the smaller the murmur
OSCE tips for VSD?
- Know the difference between cyanotic and acyanotic heart defect presentations
- Remember the grading system for murmur classifications
- The VSD murmur is heard loudest over left sternal border
Murmur grades
how many grades are there?
6
Outline the murmur grades
Is ASD a cyanotic or acyanotic heart defect?
a) Acyanotic b) Cyanotic c) Both
a) Acyanotic
It causes a left to right shunt making it acyanotic
What type of murmur does ASD create?
a) Early diastolic
b) Pan systolic
c) Systolic ejection
d) Machine-like continuous
c) Systolic ejection
ASDs create a systolic ejection murmur!
What is the gold standard investigation for diagnosing ASD?
a) Chest X-ray
b) Pulse oximetry
c) ECG
d) Echocardiogram
d) Echocardiogram
An echo allows you to directly visualise the atrial septum and the size of the ASD
What is ‘Atrial septal defect’
- It is an acyanotic heart defect
- An opening in the atrial septum, excluding a patent foramen ovale.
- This causes a left to right heart shunt because pressure is higher in the left atrium than the right.
How many types of ASDs are there
And what are they?
There are 4 types of ASD:
Ostium secundum,
ostium primum
sinus venosus
unroofed coronary sinus.
What is Atrial septum development:
- Septum primum grows down, creating ostium primum which closes as septum primum grows further and fuses with endocardial cushions
- A hole appears in septum primum called ‘ostium secundum’
- Septum secundum grows down next to septum primum, and the hole created there is the foramen ovale
How to remember septum primum and septum secundum?
How to remember:
The septum forms first, then the hole/ostium is created as a result. Primum comes before secundum!
Presentation of right to left shunt (cyanotic)?
examples?
blue
TOF
TGA
presentation of left to right shunt (acyanotic)?
Examples
Breathless or asymptomatic
ASD, VSD, AVSD, PDA
Presentation of outflow obstruction in the well child?
examples?
asymptomatic
AS, PS, Adult type CoA
Presentation of outflow obstruction in sick infant?
Examples?
Collapsed with shock
Coarctation
Hypoplastic left heart syndrome- HLHS
Symptoms of ASD
- Asymptomatic
- Some children will have recurrent chest infections
- Diagnosed on average at age 4 from finding an incidental murmur or later in life with arrhythmias and dyspnoea
• A 6 year old girl is brought to pediatrician for routine well-child care. She is doing well, keeps up with peers in dance class. No apparent distress, but subtle right ventricular lift. Her second heart sound is widely split and doesn’t vary with respiration. She has a soft 2/6 systolic murmur best heard along left upper sternal border.
This is an example of?
ASD
child via an incidental murmur
45 year old woman seeks treatment for frequent palpitations. In her mid 20s she became slightly SOB with exertion. She’s recently been seen twice in hospital emergency for atrial tachyarrhythmias. She has a 2/6 systolic ejection murmur at her left upper sternal border which radiates to her back
ASD
Symptomatic presentation before 40 yo with arrhythmias and dyspnea.
Does down syndrome link with ASD
To note, 25% of patients have Downs syndrome
Ix for ASD
- Pulse oximetry
- Echocardiogram: Visualise defect directly.
- CXR: Usually no findings, possible cardiomegaly.
- ECG: Excludes RBBB.
Differentials for ASD
and how to differentiate?
- PDA: Bounding pulses.
- VSD: Has a holosystolic murmur.
- Pulmonary stenosis: Has a click after first heart sound
- RBBB: ECG to distinguish
What do you hear on auscultation for ASD?
Systolic ejection murmur, best heard at left upper sternal border. Often radiates to back.
- Fixed splitting of second heart sounds
OSCE tips for ASD
- When listening to murmurs differentiate when you can hear them ie in systole or diastole
- Know the difference between cyanotic and acyanotic heart defect presentations
- Remember the grading system for murmur classifications
- The ASD murmur is heard loudest over left upper sternal border
Is PDA a cyanotic or acyanotic heart defect?
a) Acyanotic
b) Cyanotic
c) Both
a) Acyanotic
Where is the ductus arteriosus located?
a) Between the pulmonary vein and aorta
b) Between the left and right atrium
c) Between the pulmonary artery and aorta
d) At the liver and IVC junction
c) Between the pulmonary artery and aorta
The ductus arteriosus is located between the pulmonary artery and aorta
What type of murmur does PDA create?
a) Early diastolic
b) Pan systolic
c) Ejection systolic crescendo-decrescendo
d) Machine-like continuous
d) Machine-like continuous
The murmur created by a PDA is a machine-like continuous murmur
What is ‘Patent ductus arteriosus’?
- Persistence of the vascular structure which connects the main pulmonary artery to the aorta, allowing blood to bypass the lungs in utero.
- It protects the lungs against circulatory overload and allows
- Shunt is right to left going from pulmonary artery to aorta because pressure is higher in pulmonary artery. This allows lungs to be bypassed.
PDA usually closes in the first __ hours after birth
48
WHat can happen if PDA does not close?
Heart failure
In an adult the remnant of PDA is known as ____________ _________
ligamentum arteriosum
After birth what happens to pressure in PDA
• Pressures change and pressure is higher in aorta so blood moves from aorta to pulmonary artery to re-enter the lungs. This means no deoxygenated blood goes around the body.
Moves oxygenated blood from right atrium to left atrium, 2/3 of the blood passes through here (right ventricle and lungs)
is this Ductus arteriosus, Foramen ovale, Ductus venosus
FO
Moves some of the remaining 1/3 of blood from pulmonary artery to aorta (so only a small amount reaches the lungs)
is this Ductus arteriosus, Foramen ovale, Ductus venosus
DA
Sphincter that constricts to pass most of the highly oxygenated blood directly to IVC bypassing the liver. This ensures only a small amount goes to the liver.
is this Ductus arteriosus, Foramen ovale, Ductus venosus
DV
Fetal circulation recap:
The fetus receives all nutrition and O2 via placenta and waste products and CO2 and sent back via umbilical cord and placenta to be eliminated via mother’s circulation.
Placenta –> Umbilical vein –> Ductus venosus à Liver or IVC à Right atrium à FO then left atrium or right ventricle then lungs or DA to aorta….
Symptoms of PDA
- Most present 3-5 days after birth when duct begins to close.
- Small: Asymptomatic
- Moderate: Congestive heart failure with failure to thrive (poor feeding)
- Large: Poor feeding, severe failure to thrive, recurrent lower respiratory tract infections • Other common symptoms: • Tachypnoea/SOB, Exercise intolerance, Apnea, Irritability, Diaphoresis
- Preterm infants may have failure to wean from ventilation
1.5 month old infant girl is brought to pediatrician for poor feeding and poor weight gain. She sweats with feeds and tires easily. She is tachypnoeic and uninterested in bottle after a few minutes of feeding. Grade 4 continuous murmur and early diastolic rumble heard best at apex. Bounding pulses, liver is 3cm below costal margin. CXR reveals enlarged heart with prominent main pulmonary artery segment and increased pulmonary markings.
this is a diagnosis of?
PDA
Patients can be asymptomatic, have significant heart failure or may present later in life with pulmonary hypertension. It depends on the size of the PDA and whether the baby is premature.
- Premature infants with significant PDA present in early infancy with a murmur or signs of HF.
- Full term can present with same as premature or may not present until late childhood with mild exercise intolerance (if shunt is smaller).
20 week premature boy treated with surfactant however on second day of life has worsening respiratory distress with increasing ventilatory requirements. He has apnoeic episodes and has some bloody stools. He has bounding pulses and a grade 3 systolic ejection murmur can be heard in the left infraclavicular area. His abdomen is distended and on CXR his lung fields are almost completely opacified.
This is a diagnosis of?
PDA
• Premature infants with significant PDA present in early infancy with a murmur or signs of HF
Ix for PDA
• Echocardiogram: Definitive diagnostic test. 2D and/or colour Doppler evidence of a PDA. Can show diastolic flow reversal and left sides heart enlargement.
• CXR: Not very sensitive, may be completely normal. May show cardiomegaly and increased pulmonary markings.
• ECG: Not very sensitive, may be completely normal.
Differentials of PDA?
- Venous hum
- Coronary artery fistula: Continuous murmur but often heard lower in precordium
- VSD/ASD: Similar clinical history, ECG and CXR however murmur of leftà Right shunts are heard in systole
- Aortic regurgitation: Present at an older age with exercise intolerance
Clinica Exam of PDA
OSCE tips for PDA
When listening to murmurs differentiate when you can hear them
Is Tetralogy of Fallot a cyanotic or acyanotic heart defect?
a) Cyanotic
b) Acyanotic
c) Both
a) Cyanotic
What is one of the features of ToF?
a) Left ventricular hypertrophy
b) Truncus arteriosus
c) Ventricular septal defect
d) Atrial septal defect
c) Ventricular septal defect
What is the gold standard investigation for diagnosing ToF?
a) Chest X-ray
b) Pulse oximetry
c) ECG
d) Echocardiogram
d) Echocardiogram
What is ‘Tetralogy of Fallot’
It is the commonest cyanotic congenital heart condition with 4 heart abnormalities
• This results in right to left shunting of deoxygenated blood at VSD (ventricular septal defect) level
What are the 4 heart abnormalities in TOF
- Ventricular septal defect
- Over-riding aorta (overrides VSD)
- Right ventricular outflow obstruction (narrowed infundibulum)
- RV hypertrophy (secondary to outflow obstruction)
Patho of TOF
- The narrowing of the pulmonary artery makes it hard for deoxygenated blood to get to the lungs
- Blood can move more easily into the left ventricle than the lungs via the VSD
- Deoxygenated blood bypasses the lungs and goes straight around the rest of the body
Symptoms and clinical examination: of TOF
- Tetralogy of Fallot will often present during day 3-5 when a PDA begins to close
- Cyanosis (degree can vary- can be subtle)
- Poor feeding
- Sweating during feeds
- Hypercyanotic episodes: Crying, breathing deeply and rapidly but not in significant respiratory distress
- Tachypnoea
- Harsh systolic ejection murmur
A 1 day old infant born at full term by uncomplicated spontaneous vaginal delivery is noted to have cyanosis of oral mucosa. Baby otherwise appears comfortable. On examination, RR is 40 and pulse oximetry is 80%. A right ventricular lift is palpated, S1 is normal, S2 is single, a harsh 3/6 systolic ejection murmur is heard at left upper sternal border
What is the diagnosis?
TOF
A baby could have hyper-cyanotic spells that are episodic and the typically murmur heard may disappear during this time. This presentation is particularly life threatening so requires rapid intervention.
What si the diagnosis?
TOF
Ix for TOF
- Echocardiogram: Gold standard investigation- definitive test
- Pulse oximetry: Normal or low (depends on degree of pulmonary stenosis)
- ECG: Reveals right axis deviation due to right ventricular hypertrophy (hard to interpret on neonate)
- CXR: Boot shaped heart (if normal, doesn’t exclude ToF)
- Hyperoxygenation test: no significant increase in PaO2
Differential Diagnosis of TOF
- Other cyanotic congenital cardiac abnormalities eg: hypoplastic left heart syndrome, transposition of great arteries, truncus arteriosus, tricuspid atresia etc (would have no change in PaO2 with hyperoxia test)
- Pulmonary stenosis (hard to differentiate clinically from ToF so needs echocardiogram)
- VSD (hard to differentiate clinically from ToF so needs echocardiogram)
- Primary pulmonary disease
Clinical examination of TOF
- Newborn baby examination completed at birth
- Cyanotic
- May be in an episode of breathing rapidly
- Harsh systolic ejection murmur
OSCE tips for TOF
- Know the difference between cyanotic and acyanotic heart defect presentations
- Remember the grading system for murmur classifications
- The ToF murmur is heard loudest over upper-left sternal angle
