Cardiac Flashcards
What kind of shunts cause breathlessness?
left to right shunts
They drive oxygenated blood into lungs > less oxygenated blood to body > dyspnoea to attempt to compensatw
What are the left to right shunts?
VSD
ASD
PDA
AVSD
What kind of shunts cause cyanosis
right to left shunts
they drive deoxygenated blood from the R side of heart into the L side of circulation > into body
What are the right to left shunts?
Tetralogy of fallot
Transposition of great arteries
What is the function of the foramen ovale
allow blood to flow from R atrium to L A > systemic circulation
This is useful in a foetus because blood in R atrium comes from umbilical vein: it is oxygenated
Why does the foramen ovale shut
Due to changes in pressure
After birth
When resistance to pulmonary blood flow falls (due to breathing)
And volume of blood returning to right atrium falls (due to placenta being excluded)
What does the ductus arteriosus connect?
Pulmonary artery to aorta
Allows pulmonary blood to bypass the lungs
What are features of an innocent ejection murmur
InnoSSSSent
aSymptomatic
Soft blowing
Systolic only (not diastolic)
left Sternal ege
How do you manage heart failure
Reduce preload - DIURETICS e.g furosemide
Enhance contractility e.g. dopamine, digoxin
Reduce afterload e.g. ACe inhibitors, hydralazine
WHat does central cyanosis present as
Tongue is slate blue
What does peripheral cyanosis present as
Child is cold / unwell or with polycythaemia
What investigations must you get for chanosis
CXR, ECG
Echo with doppler
Specialist opinion
What are complications of heart disease in children?
Heart failure, SOB
Faltering growth
Recurrent chest infections
Infective endocaridtis
What are the two types of atrial septal defect
Secundum ASD
Partial AVSD
What is secundum ASD
Large defect in ASD, involves foramen ovale
How does ASD present
No symptoms
Reccurent chest infections / wheeze
Arrythmia (from 40yo)
What are ASD murmur
Ejection systolic murmur
Split second heart sound
What physical effect does ASD have on the heart
right ventricular dilatation
How do you manage ASD
OBSERVATION: as defect may close / shrink over time
Measure ratio of pulmonary:systemic blood flow
- <1.5 no closure
- > 1.5 or ASD large enough to cause RV dilatation: closure
Secundum:; cardiac catheterisation, insert occlusive device
Partial: surgical correction
What age is ASD treated at
3-5 years old
What is a ventricular septal defect categorised as
Small = smaller than aortic valve Large = larger than aortic valve
What is the murmur occurring with large VSD
pansystolic
When should the ductus arteriosus close
1 month after expected delivery date
How do you manage patent ductus arteriosus
Close using coil / occlusive device through cardiac catheter
What test shows RtL shunt?
Hyperoxia (Nitrogen Washout) test
How does Hyperoxia (Nitrogen Washout) test work
place infant in 100% oxygen for 10 minutes
if PaO2 stays low (<15kPA)»_space; CYANOTIC HEART DISEASE
How do you manage a cyanosed neonate
ABC > artificial ventilation if necessary
Start prostaglandin infusion immediately to maintain duct patency (key for survival)
Surgery at 6 months
What kind of blood movement occurs in cyanotic heart disease (RtL shunt)
deoxygenated blood into systemic circulation
What are the abnormalities in tetralogy of fallot
Ruksana Validates Orkid’s Patheticness
RV hypertrophy
VSD
Overriding aorta
Pulmonary artery stenosis
What is the outcome of the tetralogy of fallot
Excessive strain on RV
What is the key presentation in TOF
Severe cyanosis
Hypercyanotic spells
Squyatting on exercise
When does TOF present
Cyanosis within months / yeara
Worse when crying / feeding
What murmur occurs in TOF
LOUD ejection systolic
What is CXR presentation in TOF
boot shaped heart
What is the TGA
aorta and pulmonary arteries swap places
So two completely independent systems form
Incompatible with life, but foetus survives in utero due to patent ductus arteriosus
When does TGA present in neonate
within DAYS !!!!
as soon as ductus arteriosus closes
What is CXR appearance of TGA
Egg on stick
What surgery is done in TGA
Balloon atrial septostomy - break flap valve of foramen ovale and encourage mixing of blood
then Arterial Switch procedure
What is Eisenmenger syndrome aetiology
Large Left to right shunt not treated early
Causes pulmonary arteries to become hypertrophied, resistance to flow increases > increased pulmonary vascular resistance > RIGHT TO LEFT SHUNT FORMED
How does Eisenmenger syndrome present
20-40 year olds Triad CHE - Cyanosis - HF - Erythrocytosis
What is the treatment for Eisenmenger syndrome
heart-lung transplant
Who is ASVD common in
Down syndrome
What is ASVD
large valve stretching across entire atrio ventricular junction
What are outflow obstructions that occur in a well child
Aortic stenosis
Pulmonary stenosis
Aortic coarctation
Explain aortic stenosis
Aortic valve leaflets fuse together
this restricts exit from left vntricle
How do you treat aortic stenosis
balloon valvulotomy / aortic valve replacement
What are aortic stenosis feratures
reduced exercise tolerance
chest pain
syncope
what is aortic coarctation
narrowing of the aorta
what are features of adult aortic coarctation
gets progressively more severe asymptomatic systemic HTN in right arm Ejection systolic murmur Radio femoral delay
What signs present on CXR in aortic coarctation
Rib notching (due to delevlopmentof large collatewral intercostal arteries() 3 sign (visible notch(
How do you manage aortic coarctation
stent
what are features of child aortic coarctation
acute circulatory collapse on day two when ductus closes
What is rheumatic fever
Multisystem immune response to preceding infection with group A beta haemolytic strep
How many people does RF progress to RHD
up to 80%
What are sx of Rheumatic fever
2-6 weeks after pharyngeal / skin infection
Polyarthritis, fever, malaise
How do you treat RHD
Aspirin (suppress inflammatory response of joint and heart)
Anti-strep antibiotics (PenV, benzylpenicillin, amoxicillin)
Corticosteroids
Who do you give prophylaxis to prevemnt RHD
Until age of 21 / 10 years after RF
What is prophylaxis for RHD
benzathine penicillin MONTHLY for 10 years since last episode or until age of 21
What criteria are used for RF diagnosis
Jones criteria
What investigations do you do for IE
Blood cultures
Echo (vegetations on valve leaflet)
What is the most coommon pathogen to cause IE
Strep Viridans
What is treatment for Strep viridans on native / prosthetic valves
beta lactam + gentamycin, 6 weeks
what are presenting signs of PDA
left subclavian thrill continuous machinery murmur large volume, bounding, collapsing pulse wide pulse pressure heaving apex beat
How do you manage aortic coarctation in neonates (usually presenting at 48h old, when DA closes)
Prostaglandin infusion to maintain patency
Surgical repaair
How do you manage SVT
if haemodynamically stable: vagal maneuvres, adenosine
If unstable: cardioversion
How do you manage tetralogy of fallot
prostaglandin infusion
Blalock Taussig shunt
Definitive surgery to repair defect from 4m onward
What is Blalock Taussig shunt
artificial tube between subclavian artery and pulmonary artery
What dwefects are repaired by surgery in TOF
Close VSD
Relieve right ventricle outflow obstruction
How do you manage hypercyanotic spells in TOF
- place patient in knees to chest position
- aadminister oxygen
- IV line > phenylpeprhine, morphine suplhate, propanolol
- sodium bicarb if prolonged attacks
- refer. to cardiac centree
describe a hypercyanotic spell in TOF
attack of paroxysmal hyperpnoea and increased cyanosis
occur spontaneously OR after feeding/prolonged crying/defcation
How do you manage tricuspid atresia
Medical: prostaglandin infusion + cardioresp support (oxygen, mechanical vent, inotropes, IV fluid)
Blalock Taussig shunt insertion > corrective surgery
What sound do you hear in VSD
loud pansystolic murmur at lower left sternal edge
Quiet pulmonary second heart sound
How do youm manage VSD
Observation (small shunts close spontaneously)
Prophylactic amox if high risk of developing endocarditis
large VSD: open heart surgerty
what are side effects of prostaglandins
apnoea
jittering
seizures
flushing
vasodilation
hypotensions
what are the top causes of a grey baby who is cyanotic at 3-5 days
sepsis
TGA
inborn errors of metabolism
NAI
