15-Critical congenital heart defects in neonates (ASSOCIATED DEFECTS…
15-Critical congenital heart defects in neonates
Left-to-right shunts(non-cyanotic). From high pressure to low pressure.
atrial septal defects
Ventricular septal defects
Most common CHD
Persistent ductus arteriosus
If eventually pulm. pressure exceeds aortic pressure --> cyanotic legs, because arteries to upper ex. leave aorta proximal to ductus a. Called Eisenmenger syndrome
Treatment: Indomethacin. NSAID, inhibit prostaglandin E2, which keep it open.
Kept open by prostaglandins
Right to left shunt(cyanotic)
Tetralogy of Fallot; 10%
Pulmonary outlet obstruction
Right ventricular hypertrophy
VEntricular septal defect
Overriding aorta - displaced to the right ventricle, overriding the septal defect.
Transposition of the great arteries; 5%
dextro TGA: pulmonary a. and aorta switch places.
dTGA lead to death, if no patent shunting is present. No symptoms during intrauterine life.
Separate pulm and syst circulations without mixing.
levoTGA: right and left ventricle switch places.
Progress to heart failure, due to higher workload for right atrium.
Tricuspid atresia; 2%
never developed. RIght ventricle become hypoplastic.
ASD, PDA or VSD needed to sustain life.
Treat: PGE1 to keep shunts open.
pulm. a. and aorta has common outlet, mixing the blood.
total anomalous pulmonary venous return.
How to differentiate?
Oxygenize for 10min - if still cyanotic or low PaO2 in right upper ex.=cyanotic:right to left.
ASSOCIATED DEFECTS (VACTERL)
Critical congenital heart defects
CHD is the most common cong. disorder in newborns. 9/1000 births
Definition Critical CHD: Those requiering surgery or chateter in the first year of life.
25% of CHD cases
Examples: Hypoplastic heart (Left or R) syndrome, pulmonary atresia, Ebsteins anomaly and all the cyanotic heart defects.
Hypoplastic heart fail
1% of CHD
Most common casue of death within 1month
Unable to support systemic circulation due to small LV
Mitral, aortic valve or aortic arch defects
Patent shunting required for surviving- leading to heart failure.
Agenesis of pulm. valve
Not sustainable to life if there is no patent shunts.
tricuspid dysplasia and dysfunction. Leading to regurgitation.