Fetal Cardiac Abnormalities Flashcards
The heart begins to develop around how many weeks?
5 weeks
During the development time of the heart, paired heart tubes form and do what?
Fuse into a single heart
When does the chambers of the heart develop?
6-8 weeks
When is the heart fully developed?
10 weeks
What are three things in fetal circulation that we don’t generally have in the adult heart?
- Ductus venous
- Foramen ovale
- Ductus arteriosus
Which view rules out 1/3 of the cardiac defects?
Four chamber
If the cardiac outflows are included, then how many of the cardiac defects can be ruled out?
2/3
What are the vessels in three vessel views?
- PA
- Ao
- SVC
When is fetal echo best performed?
20-22 weeks to term
What does fetal screening of the heart allow? 2
- Alllows parental decisions and preparation
- Allows for potential medical intervention in utero and prepare for treatment post natally
Fetal screening has a huge impact for conditions with what? 3
- High risk of pre-operative mortality
- Risk of intrauterine fetal death
- Opportunity to intervene in utero
What are things that are high risk of pre-operative mortality? 2
- TGS
- Coarctation
What are risks of intrauterine fetal death? 2
- SVT
- Heart block
What are opportunities to intervene in utero? 2
- Arrhythmia
- Aortic and pulmonary stenosis
What are four indications for fetal echo?
- Abnormal fetal findings from previous ultrasound
- Family history of congenital heart defect
- Previous pregnancy with a cardiac abnormality
- Maternal diseases associated with heart defects (type 1 diabetes)
What are some fetal findings associated with heart disease? 9
- 2 vessel cord (IUA)
- Congenital diaphragmatic hernia
- Omphalocele
- Thick nuchal fold or NT
- Persistent right umbilical vein
- Hydrops
- Chromosomal abnormalities
- Bradycardia
- Tachycardia
What is the fetal echo routine? 8
- Establish situs with stomach and heart
- 4 chamber heart view
- Outflow tracts
- 3 vessel view
- Aortic arch and ductal arch
- Short axis of ventricles and atria
- SVC and IVC
- Pulmonary veins
What does normal Abdominal situs look like? 5
- Stomach bubble on left
- Desc. Aorta on left
- IVC anterior and to the right of the aortic
- Liver on the right
- Spleen behind the stomach on the left
What is the process of the cine clip of the fetal heart exam? 3
- Beginning at the level of the AC
- Slowly sweep Cephalic on the fetus
- Demonstrating anatomy (stomach, 4 chamber view, LVOT, RVOT, 3 vessel view)
When setting up the cine clip, what needs to be demonstrated at the level of the AC?
Demonstrate the fetal stomach to confirm situs
How long is a cine clip of the heat echo routine?
6-12 seconds
What is the top tip for fetal heart imaging?
Use fetal echo preset if available
Besides fetal echo present, what is some tips for fetal heart imaging? 5
- Use the highest frequency possible for your patient
- Reduce depth
- Narrow sector width/ colour box
- Reduce dynamic range
- Zoom
What is an acrynoym to help remember 4CH heart?
PASSSS
What does PASSSS stand for?
- Position: 2/3 in the left chest
- Axis: 45 degrees from midline
- Size: 1/3 of the chest
- Symmetry: RA=LA, RV=LV
- Septa: FO, IVS
- Squeeze: Qualitative assessment
In the fetal heart, the aorta arises from where?
Left ventricle
How does the aorta course in the LVOT?
Left to the right first
What is the aortic wall continuous with?
Septum
Does the aorta bifurcate?
No
What should the aortic valve look like? 2
Thin and mobile
In the fetal heart, the pulmonary artery arises from where?
Right ventricle
The fetal pulmonary artery courses how?
Anterior and to the left
Does the Pulmonary artery bifurcate?
Yes, we must see it bifurcate
What does the pulmonary valve look like?
Thin valve and mobile
What does the RVOT cross?
The LVOT at right angles
What is included in three vessel view?
From left to right and anterior to posterior:
1. Pulmonary artery
2. Aorta
3. SVC
In three vessel view, how similar is the PA and the aorta visually?
PA similar size or larger
In the 3 vessel view, the SVC and the aorta compare how visually?
SVC is smaller than aorta
In the three vessel view, What vessels dive together to left of the trachea?
Aorta and PA
What is the sizing order of three vessel view?
PA>AO>SVC
What does fetal short axis view demonstrate? 4
- Right and left atria
- Right ventricle
- Pulmonary artery
- Ductus arteriosis encircling the aorta
What does the aortic arch look like?
Candy cane
What are the three vessels in the aortic arch?
- Brachiocephalic
- Left common carotid artery
- Left subclavian artery
What does the ductal arch look like?
Hockey stick
What is the ductal arch?
When the right ventricle with ductus join the aorta
What does the SVC and the IVC do in the fetal heart?
Bring deoxygenated blood back from the body to the right atrium
What is the SVC-IVC alternative name?
Longhorn view
How many pulmonary veins do we usually see in fetal echo?
2 pulmonary veins
What is included in the fetal echo routine in terms of doppler? 4
- Inflows
- Outflows
- Ductus arteriosus
- Foramen ovale
What are four tips for pulsed doppler in the fetal routine?
- Line up the flow - parallel
- Place sampling gate after the valve
- > 1m/s consider stenosis
- Useful in rhythm assessment
What is the normal colour scale velocity for fetal valves, IVS, and venous structures? 3
- Valves: 50-80 cm/s
- IVS: 30-40cm/s
- Venous structures: ~20 cm/s
When determining the aortic arch, how do we determine the vessels?
We must determine which direction the Descending aorta and ascending aorta are
In the fetal heart, M mode is done through what?
Atrium and ventricle usually done in a four chamber view
What does M-Mode confirm in fetal echo? 3
- Viability
- Arrhythmias
- Abnormal rhythms
What are some arrhythmias that can be seen with M-mode? 2
- Heart blood
- Are the ventricles and atria contracting at the same time
What are some abnormal things that we can see in M-mode?
Premature atrial contractions
Premature atrial contractions determined in M- mode may include what? Is it malignant or benign?
- May preclude tachycardia
- Generally benign