CV125 Congenital Heart Disease Flashcards
Stenosis
narrowing of valve or artery
coarctation
narrowing of blood vessels (used specifically when talking about arteries)
atresia
complete blockage
regurgitation
valve leakage
When does the fall in Pulmonary Vascular Resistance occur in babies?
1) the first 48 hrs of life
2) full drop occurs by 2 months of age
what are the most common types of Left to Right Shunt?
1) Atrial septal defect (ASD)
2) ventricular septal defect (VSD)
3) patent ductus arteriosus
4) AV Canal defect
Describe how blood flows in an ASD
Secundum (middle part of the atrial wall) is missing. RA blood flows into the RV and into the lungs but once blood gets to the LA, the blood goes back into the RA because of the higher pressure in the LA. The lungs see more blood than they should.
What is a VSD?
A hole in the ventricular septum
what happens to SVR when the placenta is disconnected?
increase in SVR
what triggers/promotes the beginning of spontaneous closure of ductus arteriosus?
increased arterial oxygen level during first days of life which causes constriction of the smooth walls of the ductus arteriosus (it squeezes tight and closes). contraction is followed by permanent fibrosis. This is usually complete by Day 3. Permanent closure usually happens first 2-3 days of life.
what causes the closure of the foramen ovale?
increased LA pressure due to systemic vascular resistance increase.
How long does it take for the foramen ovale to close?
between 4-6 months of life
What takes longer to close, foramen ovale or ductus arteriosus?
foramen ovale
How long does it take for the majority of PVR to fall in a newborn?
This occurs in the first 48 hrs but a full drop occurs by 2 months of age.
What are factors that alter normal heart transition in the newborn?
1) prematurity because there is immature smooth muscle in ductus arteriosus making it difficult to shut
2) neonatal stress such as hypoxia, acidosis, sepsis which cause a delay in PVR drop
What are the 3 most common presenting features that alert people of congenital heart disease?
1) murmur
2) congestive heart failure
3) cyanosis
What are the 2 large groups of heart defects?
acyanotic and cyanotic
What is the difference between acyanotic and cyanotic heart defects?
Acyanotic are more common. Do not make the babies overall oxygen saturation impaired
What are the 2 types of cyanotic heart defects?
1) left to right shunt
2) obstruction
How to fix ASDs?
usually fix later in life, at 3-4 years of age to see if it fixes itself. Can detect because hear a murmur. cover hole
Describe blood flow in VSD
Blood from LV moves into the RV because of higher pressure
What is the most common congenital heart defect?
VSD
What is a patent ductus arteriosus?
when the ductus arteriosus fails to close
Describe blood flow in PDA
Because ductus arteriosus is not closed, blood from the aorta (due to high pressure) flows back into the pulmonary artery and into the lungs. Therefore, more blood goes to the lung that should.