Fetal Heart Anomalies PT 1 Flashcards
umbilical vein job?
Returns 80% saturated blood from the placenta to the fetus
Umbilical arteries function?
carry mainly deoxygenated blood back to the placenta for oxygenation
at what week does erythropoeisis take place?
week 3
Ductus venosus function?
- what does it become at birth?
- oxygenated blood from the umbilical vein isshunted away from the livervia the ductus venosus to the IVC
- becomes ligamentum venosum upon closure at birth
Foramen ovale function?
- what does it become?
- oxygenated blood entering the right atrium isdiverted from the lungsthrough the foramen ovale into the left atrium to deliver oxygenated blood to the body
- closes after birth and becomes fossa ovalis
Ductus arteriosusfunction?
- what does it become?
- connects pulmonary artery to aortic arch
- deoxygenated blood that enters the right ventricle to be pumped through the pulmonary arteries is mostly diverted from the lungs to the body into the aortic arch via the ductus arteriosus
- becomesligamentum arteriosumupon closure at birth
Dextrocardia?
- Heart is located in the right side of the chest with apex pointing to the right
- reciprocal of levocardia
Dextroposition
- mortality rate?
- heart is located in the right side of chest but the apex pointing to the left
- 81% mortality
Mesocardia?
heart is located in the middle portion of the chest with the apex pointing along the midline
the heart occupies how much of thoracic area?
1/3rd
Regular cardiac rate and rhythm?
120-160 or 180bpm
What is concidered the most posterior atria?
- Left atrium
where is the left atrium located?
- relation to aorta?
- most posterior atria
- located immediately anterior to the descending aorta
What can be seen in the left atrium? (3)
- foramen ovale flap
- pulmonary veins
- atrial septum primum
What is typically larger the right or left ventricle?
Right
Where is the moderator band located?
right ventricular apex
Where is te mitral valve loacted?
between the morphologic LA and LV
Where is the tricuspid valve located?
between the morphologic RA and RV
What is seen in the 3 VV?
- 3 vessels: pulmonary artery, aorta, SVC
- trachea
What does the 3 VV enable the diagnosis of? (6)
coarctation of the aorta
right aortic arch
double aortic arch (seen in tetralogy of fallot)
Absence of a great artery
Truncus arteriosus
Transposisition of the great arteries (TGA)
What 4 things are associated with tetralogy of Fallot?
- ventricular septal defect
- thickened muscle wall
- pulmonary valve stenosis
- misplaced aorta
What is TGA? (transposition of the great arteries)
- Aorta rises from the right ventricle
- PA rises from the left ventricle
- 4-7% of all heart defects
- Simple transposition can be successfully treated with arterial switch operation within the first week of life
Truncus arteriosis?
- % of heart anomalies?
- almost always associated with?
- Single trunk supplies both the pulmonary and systemic circulation
- 2% of congenital heart abnormalites
- Almost always associated with a VSD
Truncus arteriosis prognosis?
- Due to parallel fetal circulation, truncus arteriosus does not cause any hemodynamic problem in utero
- Major problem postnatally and, if left untreated, approximately 80% of infants die within the first year
Why must fetal lie be determined?
- so the left and ride structures can be assessed
- to diagnose complex cardicac malformations accreately
Scanning plane while evaluating abdominal situs?
- level of the intrahepatic portion of the umbilical vein
Normal situs of fetus?
- aorta lies to the left
- IVc lies to the right of the spine
LVOT?
The aorta arises first, sweeping to the fetal right
RVOT?
- The pulmonary artery crosses over
- Early bifurcation into the right and left branch pulmonary arteries, characteristic of the pulmonary arter
The three vessel and trachea view
- Enables a comparison of the transverse aortic arch and ductal arch
- They should be of similar sizes.
What is the leading cause of infant mortality?
Congenital heart disease
Common indications for fetal echo?
- hydrops
- Polyhydramnios
- Fetal arrhythmia
- Chromosomal anomalies
- Family history
- Maternal disease (diabetes)
What is a sinoatrial node?
- where is it located?
- The normal regularrhythmof the heart is set by the natural pacemaker of the heart called the sinoatrial (orsinus) node
- located in the wall of the right atrium
What is the normal fetal heart rate in the 2nd and 3rd trimesters?
120-160 bpm
Irregular rhythm?
- relatively common during?
Irregular rhythm is the most common arrhythmia and relatively common during the 3rd trimester
What are most irregular rhythms due to?
premature atriam contractions (PAC’s)
What is an arrhythmia?
- Irregular rhythm
- Premature atrial or ventricular contractions
What is a complete heart block?
\complete dissociation between the atria and ventricles.
Fetal bradycardia?
- abnormally low heart rate (<100 bpm)
What is commonly seen in bradycardia?
- atrioventricular block
What does M-mose help demonstrate?
discrepancy in atrial and ventricular rates
of all arrhythmias what one has the most likelihood to be associated with a structural heart abnormality?
bradycardia
what is the most frequently associated structural defect?
artioventricular canal defect
Tachycardia?
- heart rate >180 bpm
risk factors associated with tachycardia? (2)
risk of:
- congestive heart failure
- hydrops
What is mild tachycardia?
- > 160bpm can occur as a normal variant during fetal movement
Normal fetal heart position?
- bulk of heart located in the left anterior quadrant of chest
- cardiac axis 45 degree angle to the midline
Normal range of cardiac axis?
22-75 degrees
levocardia?
- normal cardiac position and axis
actopia cordis?
- rare
- heart is located outside the thoracic cavity
what is actopia cordia a result from?
- failure of fusion of the lateral body fold in the thoracic region
4 classifications of ectopia cords?
- thoracic (60%)
- abdominal (30%)
- thoracic abdominal (7%)
- cervical (3%)
thoracic ectopia cordis?
heart displaced from the thoracic cavity through a sternal defect
abdominal ectopia cordis?
heart displaced into the abdomen through a diaphragmatic defect
thoracic abdominal ectopia cordis?
The heart is displaced from the chest through a defect in the lower sternum, with an associated diaphragmatic or ventral abdominal wall defect
what is pentalogy of cantrell?
- syndrome that causes defects involving thediaphragm,abdominal wall,pericardium,heartand lowersternum
- diagnosis made as early as 10 weeks GA
- prognosis poor
Cervical actopia cordis?
heart displaced in the neck area
atrial septal defects (ASD) results from?
an error in the amount of tissue reabsorbed or deposited in the interatrial septum
Ventricular Septal Defect (VSD)?
- seen as?
- associated with?
- seen as holes in the ventricular septum
Associated with:
- chromosomal abnormality
- diabetes
what is te most common cardiac anomaly?
Ventricular Septal Defect (VSD)
of the structural cardiac defects Ventricular Septal Defect’s have the highest?
- recurrence rate
- hightest association with teratogen exposure
What measurment is concidered a small VSD?
<2mm
Atrioventricular Septal Defect (AVSD) AKA?
endocardical cushion defect
What is Atrioventricular Septal Defect (AVSD) identified as?
- defect in the lower position of the atrial septum and upper portion of the ventricular septum
What is Atrioventricular Septal Defect (AVSD) most commonly associated with?
- Tri- 21 (30-40%)
- Complete heart block may be present due to interruption of the conduction tissue
AVSDs 3 categories?
- complete
- incomplete
- transitional
Complete AVSD?
There are defects in all structures formed by the endocardial cushions: defects (holes) in the atrial and ventricular septa, and the AV valve remains undivided or “common.”
Partial or incomplete AVSD
- Part of the ventricular septum formed by the endocardial cushions has filled in and the tricuspid and mitral valves are divided into two distinct valves
