Congenital Anomalies Flashcards
What defects are associated with 22q11 deletions?
Truncus arteriosus
Teratology of Fallot
What congenital cardiac defects are associated with Down Syndrome?
ASD
VSD
AV septal defect (endocardial cushion defect)
What congenital cardiac defects are associated with Congenital rubella?
Septal defects
PDA
Pulmonary artery stenosis
What congenital cardiac defects are associated with Turner Syndrome?
Coarctation of the aorta
What congenital cardiac defects are associated with Marfan’s Syndrome?
Aortic insufficiency and dissection
What congenital cardiac defects are associated with being an infant with a diabetic mother?
Transposition of great vessels
Normally, the pressure in the ____ heart is stronger than in the ____ side of the heart.
Normally, the pressure in the left heart is stronger than in the right side of the heart.
Acyanotic heart defect characteristics and examples:
Intracardiac or vascular stenosis
Valvular regurgitations
Left to right shunts
Examples:
- Atrial septal defect
- Ventricular septal defect
- Patent ductus arteriosus
- Congenital aortic stenosis
- Pulmonic stenosis
- Coarctation of the aorta
Cyanotic heart defect characteristics and examples:
Poorly oxygenated blood shunted from right heart to left
Blood bypasses fetal lungs
O2 sat 80-85%
The 5 T’s!
- Truncus Arteriosus
- Transposition of the great vessels
- Tricuspid atresia
- Tetralology of Fallot
- TAPVR – Total anomalous pulmonary venous return
What is the incidence of atrial septal defects?
Which kind is the most common?
1 in 1,500 live births
Ostium secundum is the most common
What are the four common forms of atrial septal defects?
Ostium secundum (most common)
Ostium primum defect
Sinus venosus defect
Patent foramen ovale (PFO)
Ostium secundum
Most common form of ASD
Due to inadequate formation of spetum secundum or excessive resorption of septum primum
Ostium primum defect:
Type of ASD
Inferior portion of the septum fails to fuse with endocardial cushions.
Sinus venosus defect:
Type of ASD, BUT not actually a true ASD - defects don’t actually occur in intra-atrial septum.
Sinus venosus defect (IVC or SVC) – related to ASDs, but mophologically distinct! “Unroofing” of area between pulm veins and RA. May have opening between LA…pathopys is similar
Patent Foramen Ovale:
20% of population!
No missing tissue, just persistence of fetal anatomy…atrial septa fail to fuse (should have occurred by 6 months).
Only an issue if RA pressures >> LA pressures.
Can be source of paradoxical emboli.
ASD pathophysiology:
Left to right shunt
Flow limited by defect size and ventricle compliance
Volume overload of the right ventricle.
What is the incidence of VSD?
1.5-3.5 per 1,000 live births
What type of VSD is most common? least common?
Membranous (70%)
Muscular (30%)
Rarely adjacent to aortic or AV valves
VSD pathophysiology
Hemodynamic changes related to defect size, SVR, and PVR
Restrictive (size of defect is the “rate limited” step for flow) vs Nonrestrictive defect (BIG defect. Pressure gradients are what determine flow)
RV, pulmonary circulation, LA and LV may all experience volume overload with time
What is the difference between a restrictive vs. nonrestrictive VSD?
Restrictive – size of defect is the “rate limited” step for flow
Non-restriticve – BIG defect. Pressure gradients are what determine flow
What symptoms suggest congestive heart failure in the infant?
Pulmonary venous congestion (left heart failure)
- Tachypnea
- Respiratory distress
- Difficulty feeding - cyanosis, sweating
Systemic Venous Congestion (Right heart failure)
- Hepatosplenomegaly
- Edema/ascites - less common
What is the incidence of PDA?
1 in 2500 - 5000 live births
PDA is associated with what risk factors?
Maternal, fetal, and environmental risk factors:
- First trimester rubella infection,
- birth at high altitude (decrease oxygen tension),
- prematurity (tissue less responsive to vasoactive substances for closure),
- sepsis,
- stress,
- hypoxia/hypercarbia/acidosis.
The ductus arteriosus usually closes due to increased _____ and decreased ____.
The ductus arteriosus usually closes due to increased oxygen tension and decreased circulating prostaglandin.
PDA pathophysiology
LA and LV overload
Potential LV dysfunction
Decreased diastolic systemic perfusion
Flow across the PDA depends of size of ductus (width and length) and relative SVR and PVR. As PVR drops with age, more L –> R shunt = pulmonary and LA/LV volume overload. …can lead to LV dysfunction. Right heart unaffected unless pulm dz develops and flow reversal.
Treatment options for PDA:
1st line - Indomethacin
Percutaneous closure
Surgical closure
What is Eisenmenger’s Syndrome?
THIS IS A CYANOTIC CONDITION! Blue kids!
Uncorrected VSD/ASD/PDA causes compensatory pulmonary vascular hypertrophy
Progressive pulmonary HTN
Shunt reversal: now Right –> Left!
Cyanosis, clubbing, polycythemia
What population does aortic stenosis occur in?
5 of 10,000 live births
Males more than Females
20% have additional cardiac abnormality
Aortic stenosis is mosty commonly due to a ____ abnormality, such as a _____ valve.
Aortic stenosis is mosty commonly due to a structural abnormality, such as a bicuspid aortic valve.
Is a bicuspid aortic valve alone problematic/dangerous?
Not really - the bicuspid valve is asymptomatic at birth, BUT will go on to fibrose and calcify with age - this is the most common cause of Aortic Stenosis in adulthood.
Can be critical and ductal dependent lesion.
Aortic stenosis pathophysiology:
High LV systemic pressure required (LVH)
High velocity jet may impact proximal aorta
Narrowed valvular orifice..requires lots of LV systemic pressure to pump blood.
Causes LVH…high velocity jet may impact proximal aorta and causes dilation of proximal aorta!
Pulmonic stenosis is associated with a ____ obstruction
Pulmonic stenosis is associated with a right ventricular outflow tract obstruction
What causes pulmonic stenosis?
Abnormal formation/regression of subendocardial mesenchymal tissue
Multiple levels of RVOT obstruction possible – VALVAR is most common
Valves can be congenitally fused, RV body muscle hypertrophy, PA obstruction. Varying severity.
Pathophysiology of Pulmonic Stenosis:
Impaired RV outflow
Right ventricular hypertrophy
May cause RV failure
Impaired RV outflow, increased RV pressures and chamber hypertrophy. Mild pulm stenosis usually doesn’t effect RV function, severe PS may result in Right heart failure
What is the incidence of coarctation of the aorta?
1 in 6000 live births
What is the etiology of coarctation of the aorta?
Etiology unclear - 2 theories:
1st theory – no flow, no grow (esp if aortic stenosis…decreased LV outflow during fetal period)
2nd theory – ectopic muscular tissue from ductus extends into aorta and constricts following birth (when ductus closes!)
Where does coarctation typically occur?
Distal to the arch, proximal to the ductus arteriosus.
Typically Juxtaductal
Area and degree of narrowing are critical for presentation.
Coarctation pathophysiology:
Distal blood flow may be compromised
May have discrepancy between upper extremity and lower extremity pressure (high in upper, lower in lower)
LVH
Collateral formation
Might be ductal dependent; based on severity
Persistent truncus arteriosus:
Cyanotic!!
Failure of truncus arteriosus to divide into pulmonary trunk and aorta
Most patients with a persistent truncus arteriosus have an accompanying ___.
ASD
What is the incidence of Transposition of the Great Arteries?
40 in 10,000 live births
What is the most common cause of cyanosis in neonates? Infants?
Neonates = Transposition of the Great Arteries
Infants = Teratology of Fallot
How does Transposition of the Great Arteries arise?
Failure of aorticopulmonary septum to spiral in a normal fashion.
Have 2 parallel circuits
Is TGA compatible with life? Why or why not?
Not compatible with life unless a shunt is present to allow adequate mxing of blood (eg VSD, ASD, PDA)
Most infants die early without intervention!
Tricuspid atresia:
Absent tricuspid valve and hypoplastic RV
Requires both ASD and VSD for viability
What is required for viability in patients with Tricuspid atresia?
ASD and VSD
What is the most common form of cyanotic congenital heart disease?
Teratology of Fallot
Incidence of Teratology of Fallot:
5 in 10,000 live births
Teratology of Fallot is often associated with other abnormalities, such as ____, ____, and ____.
Teratology of Fallot is often associated with other abnormalities, such as right-sided arch, ASD, and left coronary anomalies.
What chromosomal deletion is associated with Teratology of Fallot?
22q11
What are the 4 criteria of Teratology of Fallot?
- VSD - anterior malalignment of the interventricular septum
- Pulmonic stenosis – obstruction
- Overriding aorta – receives blood from both ventricles
- Right Ventricular Hypertrophy – due to pressure load on RV
Tetralogy of Fallot pathophysiology:
- Pulmonic stenosis causes resistance to RVOT flow
- R –> L shunt causes cyanosis
- Magnitude of shunt depends on degree of stenosis and balance of PVR and SVR
(Isolated VSDs usually have left to right shunt. In TOF, Pulmonic stenosis causes right to left shunt)
What is a Tet Spell?
- Dypsnea on “exertion” (in children, exertion is eating and crying)
- Alterations in PVR and SVR
- Worsening R –> L shunt reversal causes cyanosis
- Resolve by decreasing R –> L shunt…squatting!
Total Anomalous Pulmonary Venous Return (TAPVR):
Pulmonary veins drain into the right heart circulation
Associated with ASD +/- PDA to allow for right to left shunt to maintain CO
What cardiac defects are associated with TAPVR?
ASD and maybe PDA to allow for right to left shunt to maintain CO
