Acyanotic congenital Heart Defects Flashcards
What are some of the causes of congenital heart diseases?
- Maternal alcohol consumption
- Rubella in the first trimester
- Phenytoin ingestion in pregnancy
- Trisomy 21-at least 40% will have CHD
- Trisomy 13 and 18-at least 90% will have CHD
- Marfans syndrome
- Diabetic moms
What is the usual pressure in the right atrium?
5mmHg
What is the usual pressure in the right ventricle?
15-20mmHG
What is the usual pressure in the left atrium?
5-10mmHg
What is the usual pressure in the left ventricle?
60 mmHg
-it is usually 4 times higher than the right ventricle
What are a cyanotic heart defects?
These are congenital heart defects that do not cause cyanosis in babies
They are broken up into:
-acyanotic with left to right shunts
-acyanotic with normal pulmonary blood flow
Name acyanotic congenital defects with left to right shunts?
- VSD
- ASD
- AVSD
- PDA
HOW DO THE BABIES WITH LEFT TO RIGHT SHUNTS USUALLY PRESENT?
- Interrupted feeds and sweating when eating which leads to failure to thrive
- recurrence of LRTI
- Chest deformities like Harrison’s sulcus, pectus carinatum, precordial bulge, chest asymmetry
Name the acyanotic congenital defects with normal blood flow?
- Coarctation of the aorta
- Atrial stenosis
- Pulmonary stenosis
In which babies does PDA occur in?
-preterm babies with respiratory distress
In preterm babies, how long does the patent ductus arterious remain open for?
For about a week after birth
What type of murmur do babies with PDA present with?
-systolic continuous murmur usually heard below the left clavicle
What is the management of PDA?
We usually give NSAIDS-like ibuprofen or indomethacin or paractemol
What is the management in infants?
They usually require surgical ligation or device closure before 6-12 months even if they are asymptotic
What are the presenting symptoms that we should look for in patients in PDA?
- Bounding peripheral pulses
- Wide pulse pressure
- Palpable dorsal is pedis
Where is the foramen ovale located?
Between the atria
What does prostaglandin E2 do?
It keeps the patent ductus arterious open
With the increased pulmonary volume what is the risk?
Pulmonary hypertension is a huge risk
When does a large VSD usually develop?
Between 2-6 weeks of life
What is the most common type of congenital heart disease?
Ventricular Septal Defect
Why would children experience failure to thrive in VSD?
Because they are breathless when eating
What murmur do we expect to hear in VSD babies?
Pansystolic murmur at the left sternal edge
-mid diastolic murmur if large VSD at the apex
What would we hear if there is pulmonary hypertension?
-A loud P2
What co-existing issues should we suspect if the baby does not respond to anti-failure therapy?
- coarcation of aorta
- PDA
When do VSD’s normally close by themselves?
-by two years of life
Why should we give prophylactic amoxicillin before teeth extraction?
To prevent infective endocarditis from occurring in the right ventricle(the ventricle opposite the defect)
What two septal defects cause atrial septal defects?
- Ostium primum (in the left atrium)
2. Ostium secundum (in the right atrium)
Why is there right ventricular hypertrophy in ASD patients?
Because of the increased volume into the pulmonary circulation
What murmur can we expect with ASD?
-we can expect a grade2/6 pulmonary ejection systolic murmur with fixed splitting of the second heart sound(S2)
What can we expect on Chest X-Ray?
Large pulmonary artery with plethoric lung fields
What is the most common defect between ostium secundum and primum?
Ostium secundum is the most common defect and most require surgery or device closure before school going age
What is a AVSD defect?
They are broken into partial or complete
What is a partial AVSD?
- It only involves the ostium primum ASD only and not the VSD
- it is usually associated with mitral valve regurgitation which a left to right shunt from the left ventricle to the right atrium
What syndrome is associated with AVSD?
-Down syndrome-at least 50% of the patient have Down’s syndrome
What kind of murmurs can we expect from these patients?
- Pansystolic murmur at the left lower sternal border or apex due to mitral regurgitation
- Ejection systolic murmur due to increased blood flow through the pulmonary valve
What is a complete AVSD?
- Usually involves the ASD and VSD
- presents with a pansystolic murmur at the left lower sternal edge or the apex
What can we expect to see on ECG?
- left anterior hemiblock
- left QRS axis between 0 and -90 degrees
- RSr’ patten in lead V1 indicating right ventricular hypertrophy due top volume overload
Who is affected the most in aortic stenosis?
- it usually occurs in males, especially after the third decade of life
- if it occurs in infancy it is most likely congenital-rheumatic fever
How many leaflets are usually present in the aortic valve?
-3 leaflets (left, right and posterior leaflets)
What murmur can we expect in an older child?
- palpable thrill
- long ejection systolic murmur radiating from the second intercostal space to the neck (crescendo-decrescendo)
What do we expect to see on the chest x-ray?
We can expect an enlarged proximal aorta
What size are normal aortic valves? And what is the size of a stenosed valve?
Normal: 3-4 cm2
Stenosed: <1cm2
What is a complication of aortic stenosis?
Microangipathic haemolytic anaemia which causes schistyocytes (breakdown of red blood cells)
Is pulmonary stenosis mostly symptomatic or asymptomatic?
Mostly asymptomatic
But if symptomatic it causes right heart failure due to the right to left shunt that occurs through the foramen ovale causing cyanosis
What kind of murmur do we expect in patients with pulmonary stenosis?
Ejection systolic at the left second ICS+ ejection systolic click
What is the management of pulmonary stenosis?
Cardiac catheterisation- balloon valvuloplasty
What does coarctation of the aorta mean?
-it means the narrowing of the aorta
Where does the coarctation usually occur?
After the subclavian artery and before the patent ductus arterious
How do we diagnose coarctation of aorta?
The arm pulses are usually more palpable than the femoral pulses
-there is a large pulse pressure between the systolic and diastolic pressures >20mmHg
What murmur do we expect in coarcation of the aorta?
Systolic murmur at the back(between the spine and the left scapula)
How many babies have associated abnormalities like ASD and VSD?
2/3 of babies
What may present in older children and adults?
-headaches, chest pain and cerebrovascular accidents(like berry aneurysms because of the increased pressure)
What can we expect on chest X-ray for older children and adults for coarctation of the aorta?
- Left ventricular hypertrophy due to concentric hypertrophy-
- the ascending aorta is enlarged and figure 3 sign
- a big radiological sign is the notching of the inferior edges of the 3rd and 8th ribs
What causes the notching of the inferior edges of the 3rd and 8th ribs?
-it is caused by enlarged collateral intercostal arteries
By when should we ensure we do the elective surgical repair?
By 2 years
When should we be worried by Takayasu’s?
If the child is presenting with congestive cardiac failure and is above 1 years old
What are the chest wall deformities that children with acyanotic heart lesions present with?
- Harrisons sulcus
- Pectus excavatum
- Precocial bulge
- Chest wall asymmetry
