Class 19: Fetal Heart Flashcards
what is the great vessel on the right side of the heart?
pulmonary artery
what is the great vessel on the left side of the heart?
aorta
what is the AV valve on the right side of the heart?
tricuspid
what is the AV valve on the left side of the heart?
bicuspid/mitral
what is the semilunar valve on the right side of the heart?
pulmonary valve
what is the semilunar valve on the left side of the heart?
aortic valve
what does the aortic arch branch of to? (4)
- descending AO
- brachiocephalic artery
- LCCA
- LT subclavian artery
the ___ exchanges O2 & CO2 from fetal circulation to mom’s circulation
placenta
why does fetal circulation shunt most blood away from fetal lungs?
fetal lungs aren’t needed – blood is shunted to more important locations
at birth, circulation changes occur due to ___ changes
pressure changes
circulation of O2-rich blood in fetus (start from UV)
UV –> ductus venosus –> IVC –> RA –> foramen ovale –> LA –> LV –> AAO –> brain
circulation of O2-medium blood in fetus (start from UV)
UV –> LPV –> HVS –> IVC –> RA –> RV –> PA –> ductus arteriosus –> AO arch/prox DAO –> lower body & trunk
the ductus venosus shunts blood away from the ___ to the ___
liver to the IVC
the ductus venosus is regulated by a __
sphincter
the ductus arteriosus prevents what?
protects the lungs from circulatory overload
the ductus arteriosus allows the ___ to strengthen
right ventricle
after birth, the ductus venosus becomes the ___
ligamentum venosum (LV of liver)
after birth, the ductus arteriosus becomes the ___
ligamentum arteriosum (at pulmonary trunk)
after birth, the foramen ovale becomes the ___
fossa ovalis
after birth, the umbilical vein becomes the ___
ligamentum teres (LT)/round ligament
after birth, the umbilical arteries become the ___
umbilical ligaments
the 4 chamber view of the heart can be achieved 99% of the time at ___ weeks
20+ weeks
the 4 chamber view rules out about ___% of heart abnormalities
65%
what is the normal heart rate of the fetus?
~120-160 BPM
what is levocardia?
when the apex of the heart points to the left
what is the normal angle of the fetal heart?
45 degrees
which is bigger: left or right atrium?
they should be around the same size
which is bigger: left or right ventricle?
RV is a little bigger
why is the right ventricle slightly larger than the left?
the RV has a thick muscular mediator band
which chamber of the heart is closest to the spine?
left atrium
which chamber of the heart is closest to the anterior chest wall?
right ventricle
the __ valve lies a bit inferior to the ___
tricuspid; mitral
the 4C view assesses all of the following except:
- ventricle & atria size
- intact septums
- AV valve movement
- echogenic foci
- ductus arteriosus
ductus arteriosus; it assesses the foramen ovale
what does the LVOT show?
the LV giving rise to the AAO
what does the RVOT show?
the RV giving rise to the pulmonary artery
how do the LVOT & RVOT look on US?
cross-perpendicular
what is the most common form of congenital heart disease?
VSD – ventricular septal defect
what does VSD do?
allows mixing of O2 rich & O2 poor blood
why are atrial septal defects hard to diagnose in the fetus?
foramen ovale
what is ventricular hypertrophy?
the enlargement of 1+ ventricles
ventricular hypertrophy is associated with which 2 types of stenosis/obstructions?
- aortic valve stenosis
- pulmonary valve stenosis
with hypoplastic heart syndrome, which ventricle is affected more often?
left ventricle
what happens to the side of the heart affected by hypoplastic heart syndrome?
the entire side is smaller
what is coarctation of the aorta?
narrowing of the aorta
where are the 2 locations where coarctation of the aorta are most common?
- distal to left subclavian artery
- level of aortic valve
to view coarctation of the AO, we want to use the 4 chamber view on US. T/F?
false – 5 chamber view
what are the most common defects associated with turner’s syndrome?
coarctation of the aorta & VSD
what is endocardial cushion defect another name for?
atrioventricular valve defects
what are AV defects?
when the AV orifice fails to separate into tricuspid & bicuspid valves, leading to hypoplastic AV valves
types of endocardial cushion defects?
- complete AV canal
- partial AV canal
when using color doppler to evaluate AV defects, what does the sonographer commonly see?
the letter “H”
which trisomy are endocardial cushion defects associated with?
trisomy 21
what are the 4 characteristics of the tetralogy of fallot & how are they related to each other?
(1) VSD dt (2) overriding AO
(3) pulmonary stenosis –> RV works harder –> (4) RV hypertrophy
what does an overriding aorta look like on US?
the letter “Y”
to view an overriding AO, which U/S view does the sonographer want to use: 4C or 5C?
5 chamber view
what is ebstein’s malformation?
1 or 2 of 3 leaflets of the tricuspid valve are displaced, leading to an incompetent tricuspid valve & malformation
which atrium may be enlarged with ebstein’s anomaly
right atrium
how does transposition of the great arteries look like on US?
when viewing RVOT, vessels (pulmonary artery & AAO) are parallel instead of perpendicular
how do infants survive with transposition of the great arteries?
only if a shunt is placed between 2 sides of the heart
what is truncus arteriosus?
when 1 large blood vessel comes out of the heart instead of 2 separate vessels (AO & PA)
