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Congenital Heart Disease
Epidemiology
Physiology
Incidence 8/1000; >75% survive first few months; 15% have >1 cardiac abnormality
Innocent
murmurs
Venous hum: high pitched continuous murmur over base of heart, neck, SCJ; varies with respiration and position of
head; disappears on lying down
Vibratory murmur: short, buzzing mid-systolic murmur at L sternal edge / apex; louder on lying down, softer on
standing
Pul flow murmur: soft blowing ejection SM over pul area; prominent with exercise, fever, anaemia
Loud, pan-systolic / diastolic; assoc with symptoms or thrill; radiate; not brief
Non-innocent
murmurs
Duct
dependent
lesions
Depend on flow through PDA to provide systemic / pul
flow
Discovered in 1st - 3rd week of life (ie. Neonatal
period) with shock and CV collapse (when
closure of ductus arteriosus causes rapid
decompensation)
Acyanotic: Coarctation of aorta
Critical aortic stenosis
Hypoplastic L heart syndrome
Cyanotic: TGA
Pul atresia / stenosis
Hypoplastic R heart syndrome
Examination: check all BP’s, L and R hand SaO2; metabolic acidosis; maybe cyanosis
Ix: blood gas; ECG and CXR
Mng with PGE2: to re-open PDA; 0.05-0.15mcg/kg/min
Mng
Avoid O2: vasodilator causing decr pul vasc resistance  incr LR shunt  incr pul blood flow
vasoC of PDA  decreases RL flow across PDA
Acyanotic
heart disease
75%
congenital
heart disease
LR
CCF
Cyanotic
heart disease
25%
congenital
heart disease
RL
 giving O2 may help if pul HTN or vasoC; however may cause pul vasc overcirculation  steal systemic blood
flow if PDA and duct-dependent flow  worsen systemic perfusion
Only give O2 if signs and Sx of inadequate tissue perfusion, or if O2 sats significantly below their normal baseline
PGE1 0.1mcg/kg/min  opens PDA  improvement of systemic flow in mins  titrate down to lowest effective
dose (usually 0.05mcg/kg/min)
IVF 10ml/kg bolus to incr preload and CO
NaHCO3 1-2mmol/kg for severe metabolic acidosis (pH <7)
Maybe pressors (eg. Dopamine, dobutamine)
Give empiric Abx as cannot exclude sepsis
Presents after 1-3/12 with CCF (when pul resistances decreases and hence LR shunt increases  pul
overcirculation); CXR tends to show cardiomegaly and incr lung markings
Causes: ASD (PFO) – 10% congenital heart disease
VSD – 25% congenital heart disease (most common)
Patent ductus arteriosus – 10% congenital heart disease; normally closes at 15hrs  closes completely by
3/52  ligamentum arteriosum
Common AV canal – 3% congenital heart disease; strongly assoc with Downs
Coarctation of aorta – pul HTN develops with closure of PDA  CCF; weak pulses in legs; ash-grey colour
Hypoplastic L heart syndrome – decr LV outflow; systemic blood flow based entirely on PDA; CV collapse
with closure; single heart sound
Aortic stenosis – 6% congenital heart disease; CCF if severe; harsh SM to neck
Causes: LR shunt  pul overcirculation  incr preload (eg. VSD, AVSD, truncus arteriosus, PDA; will present in 1st
3/12)
Acute L heart obstruction (eg. AS, COA  incr afterload; will present in 1st 1/52)
1Y myocardial  decr inotropic function (eg. Cardiomyopathy, myocarditis; can present at any age)
Other (eg. Anaemia, metabolic, toxic; usually presents on D1, unlike other causes)
Sx: SOB after feeding, poor feeding, sweating, incr RR, incr HR, cardiomegaly, gallop rhythm, thrill, enlarged liver /
spleen, incr incidence chest infections, weak pulse, FTT, fatigue; pul rales; incr WOB; no peri oedema
Mng
O2: may causes worsened shunt as above, so aim SaO2 no more than 95%
Elevate head of bed; if give IVF, be careful
Frusemide 1-2mg/kg IV  PO frusemide and spironolactone
Digoxin (for inotrope): 40mcg/kg if >1/12, 30mcg/kg if <1/12, 20mcg/kg if prem – give ½ dose as bolus  ¼ 8-12hrs
later  ¼ 8-12hrs later
Consider dopamine / dobutamine (5-10mcg/kg/min)
Consider nitroprusside, Ca channel blockers in consultation with cardiologist
Causes: caused by mixing of oxygenated and deoxygenated blood
Tetralogy of Fallot
Transposition of great arteries (mixing occurs through concurrent ASD / VSD)
Tricuspid problems (eg. Tricuspid atresia, Ebstein’s anomaly)
Truncus arteriosus
Total anomalous pul venous return
Eisenmeger’s syndrome (large uncorrected ASD / VSD; occurs later as infant / child)
Other: persistent fetal circulation (caused by structural heart disease, meconium aspiration, pneumonia,
sepsis, pul HTN)  blood shunts RL through PFO / ASD / VSD
Sx: effortless incr RR, polycythaemia; presents in neonatal period with cyanotic spells; for cyanosis to be
present, SaO2 70-80%
Ix: hyperoxia test: measure PaO2  15min high flow O2  measure PaO2  should rise by 20mmHg, if not =
cyanotic heart disease
Tetralogy of
Fallot
RL
10%
congenital
heart disease
Most
common
cyanotic
heart disease
1. Pul stenosis +/- hypoplastic pul artery  RV outflow obstruction ( ESM
with thrill in pul area, and at L sternal edge radiating to back)
2. RVH ( RV heave)
3. Large VSD – subaortic perimembranous; R  L shunt to aorta
4. Over-riding aorta (aortic root overlying septum and VSD;  ejection
click)
If assoc with ASD (in 10%) = pentalogy of Fallot
Cyanosis due to infundibular spasm and decr pul blood flow; degree of
cyanosis depends on extent of RV outflow obstruction and hence how much
blood is shunted RL
Sx: onset of cyanosis in 1st few wks/mths of life; cyanosed after feeding, squatting after exercise (decr return of
desaturated blood from legs, incr aortic p, incr afterload  decr size of RL shunt)
Tet spells: caused by RV outflow tract obstruction / changes in vascular resistance (may also occur in patients with
pul stenosis)  decr SVR and pul blood flow  RL shunting through VSD; precipitated by crying, fever,
dehydration, incr RR, incr HR, defecation, feeding, anaphylaxis, hypoxia, acidosis; present with period of
inconsolable crying, incr RR, incr cyanosis, decr intensity of heart murmur, limpness, seizures; most common in 46/12; complications are due to prolonged hypoxia
Examination: murmurs as above
clubbing, cyanosis, loud S2; normal pulses, continuous PDA murmur
Ix: ECG: ventricular arrhythmias in 40%; AF, flutter common; RAD; RAH; RVH; tall peaked T waves
CXR: small pul arts (due to decr blood flow); boot shaped heart (due to RVH); oligaemic lung fields; no
Cardiomegaly
Mng: trt by decreasing SVR, HR, agitation, infundibular spasm  decreasing RL shunt
Of Tet spells: aim is to incr pul blood flow by increasing preload, provide pul vasoD, incr afterload to reverse
RL shunting
1. O2 100% (usually has little effect though; causes pul vasoD)
1. knees bent posture (incr VR, incr SVR); rest; abdo compression; calm child
1. morphine 0.1-0.2mg/kg IV/IM (decr catecholamines, decr RR)
2. IVF 10-20ml/kg (incr preload, decr dynamic outflow obstruction; give this before drugs that
may cause hypotension)
3. HCO3 1-2mmol/kg IV (corrects acidosis, promotes pul vasoD) – repeat at 10-15mins
4. metaraminol 50mcg/kg IV over 10-15mins  0.25-1mcg/kg/min infusion (incr afterload 
decr RL shunt)
4. esmolol 500mcg/kg over 1min  50mcg/kg/min infusion (decr RV outflow obstruction via decr
infundibular spasm, incr pul outflow)
5. ketamine, RSI
Of TOF: corrective surgery (when v young, <1% surgical mortality in children; 90% 30yr survival with good
levels of function)
early palliative OT if severely ill (pul valvuloplasty to incr pul art blood flow)
Complications: Tet spells, polycythaemia ( thrombosis), consumptive coagulopathy, endocarditis
Transposition
of great
vessels
RL
5-8%
congenital
heart disease
Epidemiology: most common cyanotic lesion manifesting in newborn
period
Only compatible with life if mixing of R and L circulations – VSD (in 2040%), ASD, PDA (3)
Sx: onset of severe cyanosis within hours (ie. PDA dependent)
unresponsive to O2
Examination: loud S2; no audible murmurs (SM if VSD)
Ix: CXR: cardiomegaly; egg shaped heart; incr pul vasculature
ECG: RAD, RVH
Mng: urgent balloon atrial septoplasty will provide rapid improvement;
arterial-switch operation (low mortality, excellent long-term outcome)
Pathophysiology: leaflets of tricuspid valve displaced into
RV, portion of RV located in RA  tricuspid regurg
(sometimes stenosis); ASD in 80%
Sx: vary from very mild to very severe; cyanosis worsens
with increased RL shunt through ASD
Examination: wide split S1 and S2; S3 and S4; SM at lower L
sternal edge (due to TR); hepatomegaly
Ix: ECG: P pulmonale, RBBB, 1st deg HB
CXR: cardiomegaly, RA enlargement, decr pul vasc
Markings
Mng: temporary arterial shunt from LR if severe to incr
pul blood flow; repair
Ebstein’s
anomaly
RL
Triscuspid
atresia
1-2%
congenital
heart disease
No tricuspd valve; development of RV and pul art wrong  decr pul blood flow; needs mixing to survive (ASD, VSD,
PDA) as RA needs RL shunt in order to empty
CXR: slight cardiomegaly, pul oligaemia
ECG: RAH, LAH, LVH, superior axis
Single artery arises from heart then branches into PA and
aorta; pul blood flow may be incr ( CCF), normal or
decreased (cyanosis)
Mild cyanosis, CCF in newborn
CXR: cardiomegaly, pul plethora
ECG: LVH and RVH
Persistent
truncus
arteriosus
RL
<1%
congenital
heart disease
Eisenmenger
syndrome
LR
becomes
RL
TAPVR
CXR summary
Pathophysiology: LR shunt  incr pul blood flow  pul HTN (incr arteriolar muscles)  becomes RL shunt;
occurs with VSD, ostium primum defect, transposition of great vessels with large shunt
Sx: haemoptysis (20%), CVA (10%), paradoxical embolism, brain abcess (5%); Sx occur in adolescents / young adults
Examination: clubbing, cyanosis; normal / high JVP; small vol pulse; RV heave; loud P2; R sided S4; murmur of
original defect disappears when Eisenmenger syndrome develops; decrescendo diastolic murmur (due to pul
regurg), pansystolic murmur (due to TR)
Ix: ECG: AF, flutter; RAD; RVH; P pulmonale
CXR: cardiomegaly; large pul art
Mng: no surgical trt avalable; maintain intravascular vol; avoid hypoxia and vasoD
1% congenital heart disease; pul veins enter into RA instead of LA; survival depends on mixing of blood (ASD, PFO);
more commonly presents with CCF than cyanosis
CXR: Snowman sign, severe cardiomegaly, incr pul markings
ECG: RAD, RVH
CXR: cardiomegaly: TOF, TGV, Ebstein’s; Eisenmeger’s; ASD; VSD
Pul. Plethora: LR shunt; TGV; patent truncus arteriosus
Pul. Oligaemia: TOF, Ebstein’s
Pul. Venous congestion: L heart obstruction
Notes from: Dunn, TinTin