Test 4 part 3 Flashcards
whatv provides groundwork for a caridac examination?
4 chamber view
what is the normal postion of the fetal heart?
left thorax with the apex directed about 45 degrees to the left
what should the size of the heart be?
less than one third of the area of the thorax and heart circumferance should be less than half of the thoracic circumferance
which side of the heart has larger chambers?
right side slightly larger
what is directly posterior to the aorta?
spine
what lies directly anterior to the aorta?
left atrium
what does long axis view of the left ventricular outflow tract show?
cresent left ventricle
what does the right ventricular outflow tract do?
wraps around anterior to the aorta
what should the normal fetal heart rate be?
have a baseline rate of 110-160 beats per minute
what may be common in early pregnancy with the heart?
bradycardia
when is bradycardia considered?
if it lasts several minutes
what is common with the heart in later stages of pregnancy and is associated with fetal movement?
tachycardia
what does the fetal heart rate become abnormal?
when it exceeds 200 beats per minute or has frequent “dropped” beats (premature ventricular contractions)
what do we assess for in the fetal heart?
- enlarged right ventricle
- hydrops
- ascites
- edema
- pleual effusion
- pericardial effusion
where should the left and right ventricles extend?
into the cardiac apex
what should sqeeze during systole?
both ventricles simultaneously
what is the moderator band?
a bright linear structure near the apex of the right ventricle
how does blood get from the heart to the lungs
blood leaves the right ventricle through the pulmonary artert via the right and left pulmonary arteries to their respective lung
what is different in the 2 ventricles?
left ventrcle is smooth walled compares with the right ventricle
what should the 4 chambers be divided by?
interatrial septum and interventricular septum to seperate the right from the left side
what is the foramen ovale?
a communication between the right and left atrial cavities in mid portion
what septum is thicker?
ventricular septum is thicker than the atrial septum
where may septal defects occur?
anywhere along the ventricular spetum with membranous defects slightly more visable than musculae defects
when is a clear view of the cardiac anatomy seen?
fetus at least 20-22 weeks of gestational age
when should a patient be offered a more detailed imaging of the fetal heart?
when the 4 chamber view and outflow tracts are abnormal
what are important additions to a fetal cardiac test?
color and doppler
what does a fetal echocardiogram always begin with?
- determination of fetal lie
- fetal number
- activity level
- location and size of placenta
- evaluation of the umbilical cord
- gestational age
- fluid assessment
what is the most common major congenital malformation with an incidence of 8:1000 live births?
congenital heart disease
what are the types of heart disease?
- tiny secundum ASD
- mild valvular pulmonary stenosis
- patent ductus arteriosus
- small muscualr or membranous VSDs
what are the risk factor catagories for congenital heart disease?
- fetal
- maternal
- familial risk factors
what are fetal risk factors for congenital heart disease?
- abnormal visceral or cardiac situs
- abnormal four-chamber view or outflow tracts
- cardiac arythmia
- aeuploidy (trisomy 21)
- 2 vessel umbilcal cord
- extracardiac structural malformation
- IUGR
- abnormal amniocentesis
- abnormal amniotic fluid collections
- abnormal heart rate
- twins
- increased nuchal translucency
- hydrops fetalis
what are the maternal risk factors for congenital heart disease?
- previous occurence in siblings or parents
- a maternal disease known to affect the baby (diabetis, connective tissue disease)
- viral syndrome (mumps)
- teratogen exposure
- maternal use of drugs such as lithium or alcohol
what are familial risk factors for congenital heart disease?
- genetic syndromes or the presence of congenital heart disease in a sibling
- if a siblng has one of the most common cardiovascular abnormalities
- when one parent has one of the common congenital heart defects there is a risk of recurrence
- syndromes (Marfan)
- tuberous sclerosis tumors in the fetal heart
what is found inferior to the aortic arch?
ductal arch
what is the most common heart diseases?
#1=VSD followed by ASDs and pulmonary stenosis
what have a high asssociation with congenital heart disease?
chromosomal abnormalities
fetuses with __________ have a 50% incidence rate of congenital heart disease, specifically AVSDs
trisomy 21
what are usually not recognized in fetal life?
ASDs
what is the most common atrial defect and occurs in the area of the foramen ovale?
secundum ASD
what ASD is technically more difficult to visualize?
the sinus venosus ASD
where does the sinus venosus lie?
in the superior portion of the atrial septum
where does the ostium primum ASD occur?
at the base of the atrial septum
where is the ostium primum ASD best imaged?
in the 4 chamber view with the cardiac chamber perpindicular to the transducer
what is the VSD septum divided into?
2 basic segments:
- thin membranous
- thicker muscular septum
muscular defects are usually _________
very small and may be multiple
what do smaller defects in the septum do?
close after birth
what is increased if VSD is visualized?
- TOF
- single ventricle
- TGA
- endocardial cushion defect
what is complete AVSD?
lack of fusion leaves a hole in the middle of the heart, with the primum atrial septum and membranous atrial septum both absent
what may happen with the valves with complete AVSD?
there may be a cleft in the mitral leaflet and overriding of the atrioventricular leaflets or chordal structures
where are the anterior and posterior leaflets?
on both sides of the interventricular septum
what view is complete AVSD best seen?
4 chamber view
what is the most common form of cyanotic heart disease and the most common major conenital heart disease associated with a totally normal 4 chamber view?
tetralogy of fallot
how does the severity of TOF vary?
according to the degree of pulmonary stenosis present
what is classified as acyanotic disease?
a large septal defect with mild to moderate pulmonary stenosis
what is considered cyanotic disease (blue baby at birth)?
a large septal defect with severe pulmonary stenosis
what is TOF associated with?
- diabetis
- tri 21
- DiGeorge syndrome
- omphalocele
- pentalogy of cantrell
what are the sonographic signs of TOF?
- high membranous VSD
- large anteriorly displaced aorta, which overrides the septal defect
- pulmonary stenosis
- right ventricular hypertrophy, which is not seen in fetal life becuase it occurs after birth when pulmonary stenosis causes increased pressures in the right ventricle
what is transposition of the great arteries?
an abnormal condition that exists when the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle
what are the 2 major types of transposition?
dextro and levo
how does TGA occcur?
transposition occurs because of an abnormal completion of the loop in embryonic development
where is the aorta usually located?
anterior and to the right of the pumonary artery
what is ebstein anomlay?
AV valve malformation-straddling of the tricuspid valve
what is hypoplastic left heart syndrome (HLHS)?
underdevelopment of the left heart
what is hypoplastic left heart syndrome associated with?
increased risk for congenital or acquired central nervous system abnormalities or aneuploidy
what is the most classic form of HLHS?
characterized by a small, hypertropied left ventricle with dysplastic aortic mital atresia
what kind of condition is HLHS?
autosomal recissive condition
