Congenital heart defects Flashcards
- The umbilical cord and vein travel within the umbilical cord
- what does the umbilical vein transport?
- what does the umbilical artery transport?
umbilical vein- nutrition and oxygen to the baby
umbilical artery- waste products and CO2 from the baby
how many foetal shunts are there
name them and explain where they shunt blood from/ to
3 foetal shunts. they bypass the lungs and liver as these organs aren’t fully functional until after birth
foramen ovale
- shunt that bypasses the lungs
- moves blood from the R atrium to the L atrium
Ductus arteriosus
- moves blood from the pulmonary artery to the aorta
Ductus venosus
- moves oxygenated blood in the umbilical vein (from placenta) to bypass the liver and empty into the vena cava
transitions at birth due to 2 actions
cord is clamped
- causes a cessation of blood flow from the placenta and a reduction in systemic vascular resistance in the baby
- this causes an ↑LS heart BP and closure of ductus venosus
baby takes first breath
- this causes a huge decrease in pulmonary vascular resistance (lung expansion, collateral tug, decreases in hypoxic pulmonary contriction)
- ↑ in pulmonary venous return to L atrium and ↑ in R atrial pressure
- pressure in L atrium > R atrium
- flap closure of foramen ovale in minutes
- systemic vascular resistance >pul vasc resistance causes flow to reverse through ductus arteriosus
- ductus arteriosus starts to close due to high ppO2 passing through it
- over subsequent weeks r vent wall reduces and left vent wall thickens
what are congenital heart defects
a variety of malformations of the heart and or its major blood vessels that are present at birth
general symptoms of CHD
- lagging physical development
- cyanosis, pallor, SOB, anxiety in breast feeding, rejection of the breast
- heart murmurs from first days of life
- increase in heart size
- ECG signs of overload and hypertrophy in different areas (p-pulmonale, p-mitrale, right type of EOS)
- radiography- increase in heart size, depletion of enhancement of pulmonary hypertension
what is the commonest CHD
the majority of cases are picked up
CHDs can be divided into (2)
ventricular septal defect
antenatally
cyanotic and acyanotic CHDs
Congenital cardiac associatations
alcohol in utero
congenital rubella
Trisomy 21 (Downs)
Mother has DM
Marfan syndrome
- alcohol in utero- VSD, ASD, PDA, TOF
- congenital rubella- PDA, Pulmonary artery Stenosis, Septal defects
- Trisomy 21 (Downs)- ASD, VSD, AVSD
- Mother has DM- TGA
- Marfan syndrome- MVP, thoracic aortic aneurysm and dissection, aortic regurgitation
Congenital cardiac associatations
- prenatal lithium
- turner syndrome
- Williams syndrome
- 22q11 (DiGeorge syndrome)
- prenatal lithium- Ebstein anomaly
- turner syndrome- Bicuspid aortic valve, coarctation of aorta
- Williams syndrome- Supraclavicular aortic stenosis
- 22q11 (DiGeorge syndrome)- Truncus arteriosus, TOF
Pink babies have
caused by a shunt from xxx to xxx
- pink babies have an acyanotic congenital heart defect
- caused by a shunt from left to right (no mixing of oxygenated and deoxygenated blood)
acyanotic pink baby CHDs can be firgher subdivided into (3)
-
Restrictive (allowing little flow from left to right)
- small ASDs/ VSDs and PDA (patent ductus arteriosus)
- may close spontaneously
-
Non- restrictive (large defects allow significant left to right flow)
- moderate- large ASDs, VSDs, AVSDs
-
Obstructive (severity of lesion decdies age of presentation)
- aortic stenosis
- co-arctation of the heart
- pulmonary stenosis
ventricular septal defect
- what colour are the babies
- example of a what kind of ASD
- symptoms
- epidemiology
- associated with what
ventricular septal defect
- pink babies (acyanotic)
- either a non-restrictive or restrictive CHD depending on size
- most common CHD
- Down’s syndrome
ventricular septal defect
- time of presentation
- clinical findings
- investigations
ventricular septal defects
management
management of ventricular septal defect
- small lesions <5mm usually close spontaneously with no repair required
- moderate lesion
- diuretic therapy (furosemide and spironolactone)
- large lesion
- as per moderate
- schedule for surgery
atrial septal defect
- what colour are the babies
- symptoms
- epidemiology
- time of presentation
atrial septal defect
-
what colour are the babies
- pink- acyanotic
-
symptoms
- typically asymptomatic, sometimes more frequent infections
-
epidemiology
- 2nd most common acyantic CHD
-
time of presentation
- mean age of diagnosis is 4.5 years from incidental finding of murmur
- sympotmatic presentation before the age of 40 years with arrhythmias and dyspnoea
atrial septal defect
- clinical features
- investigations
- management
atrial septal defect
- clinical features
- may also have auscultatory findings in infants (asymptomatic)
- ejection systolic murmur
- left specific details out
- investigations
- pulse oximetry
- ECHO
- CXR
- ECG
- management
- most children asymptomatic and require CHF therapy
- spontaneous closures in small lesions
- large defects require catheter closure
patent ductus arteriosus
example of what kind of defect
colour of baby
symptoms
epidemiology
patent ductus arteriosus
- example of what kind of defect
- acyanotic non-restrictive CHD
- colour of baby
- pink
- symptoms
- depends on size of lesion
- small- asymptomatic
- moderate- CHF with poor feeding, FTT
- epidemiology
- 5-10% of all CHD
patent ductus arteriosus
- clinical features
- investigations
- management
patent ductus arteriosus
- clinical features
- palpate liver (enlarged in heart failure)
- bounding pulses and wide pulse pressure
- continuous machinery murmur typically in ULSB best heard below left clavicle
- investigations
- ECHO and doppler
- CXR and ECG are less useful in daignosis
- management
- if preterm- spontaneous closure
- medical- ibuprofen
- surgical- catheter closure or PDA ligation
coarctation of the aorta
- colour of baby, type of CHD
- pathophysiology
- time of presentation
- clinical features
- pink baby, type of osbtructive CHD
pathophysiology
- obstruction to the LV outflow tract leads to an increase in LV afterload which causes LV hypertrophy
time of presentation
- symptoms present 3-5 days after birth when the duct begins to close as the PDA and foramen ovale allows blood to bypass the outflow obstruction
clinical features
- absent femoral pulses
- cold extremities
- hepatomegaly
coarctation of the aorta
investigations
management
coarctation of the aorta
- investigations
- ECHO and doppler
- management
- medical
- IV infusion of prostaglandin E1 to keep ductus arteriosus open
- left the details out
- medical
Cyanotic CHD babies are what colour
this is because deoxygenated blood enters the?
what are the 5 Ts of cyanotic disease
- blue
- this is because deoxygenated blood enters the systemic circulation
5T’s of cyanotic disease
- Tetralogy of fallot (TOT)
- Transposition of great arteries (TGA)
- Truncus arteriosus
- Total anomalous pulmonary venous drainage
- Tricuspid atresia (also HLHS)
quick explanations of the 5 Ts
- TOF
- TGA- aorta comes off right ventricle, PA comes off left vent (may be associated with ASD or VSD- as they allow 2 new separate systems to mix blood
- Truncus arteriosus- pulm artery and aorta haven’t divided- single common overlying blood vessel
-
Total Anomalous Pulmonary Venous Drainage- pulm veins do not connect to left atrium
- 3 types described by where the PVs connect (All have ASDs or else not compatible with life)
- -supracardiac= PVs drain into right atrium
- -Cardiac= PVs drain into the right atrium through coronary sinus
- -Infracardiac= PVs drain into RA through hepatic veins and IVC (has highest risk of obstruction)
-
Tricuspid atresia- tricuspid valve does not form (hypoplastic RV common)
- -similar defect affects left heart- hypoplastic left heart syndrome (HLHS)
- Ebsetin anomaly- displaced tricuspid leaflets, artificially atrializing the RV
tetralogy of fallot is comprised of which 4 anomalies
tetralogy of fallot is comprised of:
- Right ventricular outflow obstruction
- Ventricular septal defect
- Over-riding aorta
- Right ventricular hypertrophy
tetralogy of fallot
symptoms
epidemiology
time of presentation
tetralogy of fallot
- symptoms
- cyanosis
- poor feeding, sweating during feeds
- severity is variable
- epidemiology
- most common form of acyanosis
- time of presentation
- during neonatal periods when PDA starts to close
- identification of “tet” spells due to ↑RV to LV shunt due to pul stenosis
- identification of crescendo-decrescendo murmur with a harsh ejection systolic quality
what are the investigations for TOF
ECHO and doppler- assess location and number of VSDs and severeity of RVOTO
ECG- right atrial enlargement and RV hypertrophy (R axis deviation, prominent R waves anteriorly and S waves posteriorly)
CXR
cardiac catheterisation
- ECHO and doppler- assess location and number of VSDs and severeity of RVOTO
- ECG- right atrial enlargement and RV hypertrophy (R axis deviation, prominent R waves anteriorly and S waves posteriorly)
- CXR
- cardiac catheterisation
what is a tet spell
These occur due to a reduction in pulmonary blood flow. PBF affected by PVR and SVR due to 2 circulations mixing.
- Often precipitated by crying, pooping, feeding, dehydration, fever.
- Anything that inc PVR or dec SVR will reduce PBF
- Now more deoxy blood enters
- Baby goes hyper-cyanotic
- Hypoxia inc PVR and makes situation worse!
- Need to increase SVR – babies may lift knees to chest, kids may squat
Transposition of the great vessels
- what kind of defect
- pathophysiology
- symptoms
- time of presentation
- clinical findings
- investigations
- management
- what kind of defect
- cyanotic defect
- pathophysiology
- aorta arises from the RV and the pul artery from the LV, results in deoxygenated blood blood from RV circulating around the body
- symptoms
- cyanosis, poor feeding, sweating during feeds
- time of presentation
- neonatal period when ductus arteriosus begins to close
- clinical findings
- cyanosis, tachypnoea, murmur
- investigations
- foetal ultrasound, ECHO, CXR, ECG
- management
- balloon atrial septostomy
- arterial switch procedure
what is total anomalous pulmonary venous drainage
to sustain life there must be;
where do the pulmonary veins feed into the heart in
- supracardiac
- cardiac
- infracardiac
none of the 4 pulmonary veins feed back into the left atrium but rather into the right side of the heart
to sustain life there must be a patent ductus arteriosus
- supracardiac= PVs drain into right atrium
- Cardiac= PVs drain into the right atrium through coronary sinus
- Infracardiac= PVs drain into RA through hepatic veins and IVC (has highest risk of obstruction)
what is truncus arteriosus
a rare heart defect that present at birth (congenital)
one large blood vessel leads out of the other
what is tricuspid atresia
cyanotic CHD
- the valve that controls blood flow from the right upper chamber of the heart to the right lower chamber of the heart doesn’t form at all.
- which restricts blood flow and causes the right lower heart chamber (ventricle) to be underdeveloped
what is hypoplastic heart syndrome
- left side of the heart is critically underdeveloped.
- If your baby is born with hypoplastic left heart syndrome, the left side of the heart can’t effectively pump blood to the body. Instead, the right side of the heart must pump blood to the lungs and to the rest of the body.
- Medication to prevent closure of the connection (ductus arteriosus) between the right and left sides, followed by either surgery or a heart transplant, is necessary to treat hypoplastic left heart syndrome
what is Ebstein anomaly
cyanotic CHD
- Displacement of tricuspid valve leaflets downward into RV, artificially “atrialising” the ventricle.
- Associated with
- Tricuspid regurgitation and right HF.
- Can be caused by lithium exposure in utero.
what are the duct dependant lesions
what is eisenmenger
- Associated with septal defects and PDA shunt
- Over time, excess Pulmonary Blood Flow from Left to Right shunt causes Pulmonary Hypertension and Right Ventricular Hypertension
- When Pulmonary Vascular Resistance>Systemic Vascular Resistance, there is a functional reversal of flow from Right to Left
- Cyanosis now occurs
