TOF, DILV, DORV, Damus-Kaye-Stansel- Topic 14 Flashcards
What percent of all cyanotic heart defects are TOF?
10%
TOF is the most common cause of _________ (2) syndrome.
Blue baby
TOF has a very high association with what condition?
Down’s Syndrome
TOF involves 4 heart defects. ___ are congenital; ___ are acquired.
3, 1
What are the 4 TOF defects?
A large VSD
Pulmonary stenosis (RVOT obstruction)
An overriding aorta
RVH
Simply put, TOF is ……
an anterior-lateral displacement of the infundibular septum
Simply put, TOF is ……
an anterior-lateral displacement of the infundibular septum
Aorta and PA start as a single tube called what?
Truncus arteriosus
Aorta and PA start as a single tube divided by what? What direction does it grow?
Spiral septum; grows down and attaches to the ventricular septum which isolates the ventricles and isolates the aorta and the pulmonary artery
Aorta and PA start as a single tube divided by what? What direction does it grow?
Spiral septum; grows down and attaches to the ventricular septum which isolates the ventricles and isolates the aorta and the pulmonary artery
What is outflow tract septation?
Partitioning of the outflow tract
Truncus Arteriosus becomes….
Aorta
Conus Cordis becomes….
Pulmonary Artery
What creates the conus cordis?
Created by a septum that forms in the outflow tract from these swellings
What creates the conus cordis?
Created by a septum that forms in the outflow tract from these swellings
RSTS
right superior truncus swelling
LITS
left inferior truncus swelling
RDCS
right dorsal conus swelling
LVCS
left ventral conus swelling
LVCS
left ventral conus swelling
If the spiral septum is not midline, but shifted toward the right side of the heart- What would this cause?
Aorta opening would be large
Pulmonary opening would be small
Spiral septum would miss the septum
If the spiral septum is not midline, but shifted toward the left side of the heart- What would this cause?
Aorta opening would be small
Pulmonary opening would be too large
Spiral septum would miss the septum
If the spiral septum is not midline, but shifted toward the left side of the heart- What would this cause?
Aorta opening would be small
Pulmonary opening would be too large
Spiral septum would miss the septum
What are risk factors of TOF?
Increased risk during pregnancy:
- Alcoholium in the mother
- Diabetes
- Mother > 40 y/o
- Poor nutrition during pregnancy
- Rubella or other viral illnesses during pregnancy
What are risk factors of TOF?
Increased risk during pregnancy:
- Alcoholium in the mother
- Diabetes
- Mother > 40 y/o
- Poor nutrition during pregnancy
- Rubella or other viral illnesses during pregnancy
TOF w/ Pulmonary Atresia AKA
pseudotruncus arteriosus
Pseudotruncus Arterosus (TOF w/ PA)
Severe variant in which there is complete obstruction (atresia) of the right ventricular outflow tract (RVOT), causing an absence of the pulmonary trunk during embryonic development
How does blood shunt in TOF w/ PA?
Blood shunts completely from the right ventricle to the left where it is pumped only through the aorta. The lungs are perfused via extensive collaterals from the systemic arteries and sometimes also via the ductus arterosus
Pentalogy of Fallot
TOF with the addition of an ASD
TOF results in low oxygenation of blood due to what?
Mixing of blood in the LV via the VSD and preferential flow of the mixed blood through the aorta (because of the flow through the pulmonary valve)
R –> L shunt
What is worse in TOF w/ PA?
R –> L shunt is significantly worse
What might be the body’s response to low saturations and decreased pulmonary blood flow?
Elevate the hematocrit, it is not uncommon for these children to have hematocrits > 50%
What are symptoms of TOF?
Low blood oxygen sat w/ or w/o cyanosis "Pink tet" - no cyanosis Periods of severe hypxic spells ("tet spells") Clubbing of fingers (skin or bone enlargement around the fingernails) Difficult feeling/failure to gain weight Passing out Poor development Squatting during episodes of cyanosis
Tet Spells
Rapid, deep breathing
Fainting/loss of consciousness
cyanosis of the lips tongue and nailbeds
Irritability or uncontrolled crying
Tet Spells
Rapid, deep breathing
Fainting/loss of consciousness
cyanosis of the lips tongue and nailbeds
Irritability or uncontrolled crying
Tet Spells: What a Child Will Do
Squatting and the knee chest position will increase aortic wave reflection, increasing pressure on the left side of the heart decreasing the right to left shunt (think clamping distal to outflow)
Thus decreasing amount of deoxygenated blood entering the systemic circulation
Tet Spells: What a Child Will Do
Squatting and the knee chest position will increase aortic wave reflection, increasing pressure on the left side of the heart decreasing the right to left shunt (think clamping distal to outflow)
Thus decreasing amount of deoxygenated blood entering the systemic circulation
Blalock Taussig Shunt
Formed anastomosis between the subclavian artery and the pulmonary artery