Chapter 26: Cardiac Flashcards
(82 cards)
What kind of shunts cause cyanosis?
Right to left shunts
Why do children squat in right to left shunts?
To increase SVR and decrease right to left shunts
R -> L shunts cause cyanosis. What can this lead to?
Polycythemia, strokes, brain abscess, endocarditis
Shift from L -> R shunt to R -> L shunt
Eisenmenger’s syndrome
What causes Eisenmenger’s syndrome?
Increasing pulmonary vascular resistance (PVR) and pulmonary HTN; this condition is generally irreversible
What do left to right shunts cause?
CHF: manifests as failure to thrive, increased HR, tachypnea, hepatomegaly; CHF in children, hepatomegaly
What is the first sign of a left to right shunt?
Hepatomegaly
L -> R shunts (CHF)
VSD, ASD, PDA
R -> L shunts (cyanosis)
tetralogy of Fallot
Connection between descending aorta and left pulmonary artery (PA); blood shunted away from lungs in utero
Ductus arteriosus
Connection between portal vein and IVC; blood shunted away from liver in utero
Ductus venosum
Fetal circulation:
- To placenta
- From placenta
to placenta: 2 umbilical arteries
from placenta: 1 umbilical vein
MC congenital heat defect
VSD (L -> R shunt)
% of VSD that close spontaneously
80% (usually by age 6 months)
Usually cause symptoms after 4-6 weeks of life, as PVR decrease, and shunt increased
Large VSDs (can get CHF - tachypnea, tachycardia - and failure to thrive)
Medical treatment: VSD
Diuretics and digoxin
Usually timing of repair:
- Large VSDs (shunt > 2.5)
- Medium VSDs (shunt 2-2.5)
Large: 1 year of age
Medium: 5 years of age
Most common reason for earlier repair of VSD
Failure to thrive
L->R shunt
- Usually symptomatic when shunt > 2 -> CHF (SOB, recurrent infections)
- Can get paradoxical emboli in adulthood
- Medical tx: diuretics and digoxin
Atrial septal defect
Most common (80%); centrally located ASD
Ostium secundum
Can have mitral valve and tricuspid valve problems; frequent in Down’s syndrome
Ostium primum (or atrioventricular canal defects or endocardial cushion defects)
Usual timing of repair ASD
1-2 years of age (age 3-6 months with canal defects)
VSD
Pulmonic stenosis
Overriding aorta
RVH
Tetralogy of Fallot
MC congenital heart defect that results in cyanosis
Tetralogy of Fallot