Congenital Heart Defects Flashcards
Allows bypass of hepatic circulation
Ductus Venosus
Flow through the foremen ovals allows well oxygenated blood to bypass the high resistance
Pulmonary Circuit
Directs relatively lower oxygenated blood to flow to lower extremities
Ductus Arteriosus
Following birth, the three shunts that exist during fetal circulation close. These three shunts are the
Ductus venosus, Foramen Ovale, and Ductus arteriosus
Normally results in left to right shunt unless Eisenmenger’s is present
-Distinct from patent foramen ovale
Atrial Septal Defect
An atrial septal defect can be distinguished by a
Fixed split S2
Due to rapid equalization of pressures between right and left heart in presence of shunt
Fixed Split S2
There is evidence of right ventricular enlargement on CXR/ECG/Echocardiography with an
Atrial septal defect
We see a step-up in oxygen saturation on catheterization with an
Atrial Septal Defect
Closure of an ASD is contraindicated once
Eisenmenger’s has developed
Most commonly in the membranous or muscular portion of the ventricular septum
Ventricular Septal Defect
Although VSD’s cause left to right shunting, initially they lead to
LV not RV volume overload
Increased pulmonary blood flow can lead overtime to pulmonary hypertension and
Eisenmenger’s syndrome
Characterized by symptoms due to congestive heart failure such as tachyon earth, poor feeding, failure to thrive, etc
VSD
On ascultation, a VSD can be heard via a
Harsh holosystolic murmur at the left eternal border in 3rd or 4th intercostal space
More than 50% of small and moderate sized VSD’s will
Spontaneously close
Results when the ductus arteriosus fails to close after birth
Patent Ductus Arteriosus
First trimester rubella infection, premature birth, and high altitude are all risk factors for
PDA
The ductus arteriosus normally closes after birth due to an increase in oxygen saturation and decrease in
Prostaglandin levels
Results in volume overload and dilation of the left side of the heart
PDA
Characterized by a continuous machine-like murmur
Patent Ductus Arteriosus
Can usually be seen on Doppler echocardiography
PDA
Even the smallest of PDA’s will be closed in order to reduce the risk of
Endocarditis
PDA’s can be closed by administration of
Indomethacin
A patent ductus arteriosus can be maintained through
Prostaglandin infusion
Characterized by a harsh crescendo-decrescendo murmur
-More common in males than females
Congenital Aortic Stenosis
The harsh crescendo-decrescendo murmur in congenital aortic stenosis is loudest at the
Base
We will see evidence of LVH on ECG with
Congenital aortic stenosis
In adults, aortic stenosis is commonly caused by
Bicuspid aortic valves
Bicuspid aortic valves commonly cause aortic stenosis in adults as a result of progressive
Calcification of the leaflets
There is a strong association between congenital aortic stenosis and
Coarctation of the aorta
Most patients with coarctation of the aorta will have an abnormal
Aortic Valve
In adults, presentation and management of aortic stenosis caused by bicuspid valve calcification is very similar to presentation and management of
Calcification aortic Stenosis
Can be seen in valve itself (90%), within RV, or in pulmonary artery
Pulmonic Stenosis
Causes increased RV pressures and hypertrophy
Pulmonic Stenosis
Characterized by dyspnea on exertion and exercise intolerance
Pulmonic Stenosis
On physical exam, shows a prominent jugular a wave and late peaking crescendo-decrescendo murmur at left upper eternal border
Pulmonic Stenosis
The only right sided sound that decreases with inspiration
Pulmonic Valve Click
Shows an enlarged RV on CXR and ECG
Pulmonic Stenosis
Echocardiogram demonstrates increased gradient across pulmonic valve, elevated right sided pressures, and RVH
Pulmonic Stenosis
What is the most effective treatment of pulmonic stenosis?
Ballon valvuloplasty
What are the two cyanotic congenital heart defects
Tetralogy of fallout and transposition of the great arteries
Has the basic defect of abnormal anterior and cephalad displacement of infundibular portion of intraventricular septum
Tetralogy of Fallot
Tetralogy of Fallot results in which 4 abnormalities
VSD, subvalvular pulmonic stenosis, overriding aorta, and RVH
Results in a net right to left shunt through the VSD, resulting in cyanosis
Tetralogy of Fallot
Depends on severity of pulmonic stenosis and systemic and pulmonary vascular resistance
Degree of shunting in TOF
With TOF, children may have spells of cyanosis following activity when systemic vasodilation results in increased
Right to Left shunting
Children learn to relieve their TOF symptoms by
Squatting
A common finding on physical exam with TOF is
Clubbing
With TOF, CXR demonstrates a
“Boot shaped” Heart
Surgical closure of VSD and enlargement of subpulmonary infundibulum is the treatment for
TOF
Results in the aligning of the aorta superior to the right ventricle
-Aorta and pulmonary artery are in opposite positions than usual
Transposition of the great arteries
Places systemic and pulmonary circuits in parallel rather than in series
Transposition of the great arteries
The initial treatment for transposition of the great arteries is?
-Allows mixing of blood which is necessary to keep baby alive
Maintenance of Ductus Arteriosus through prostaglandin
When a congenital defect with left to right shunting overwhelms the pulmonary circuit and results in the direction of the shunt being switched
-Once this develops, correction of original defect is contraindicated
Eisenmenger’s Syndrome
Presentation is usually before age one, with frequent respiratory infections, poor weight gain, and heart failure
Atrioventricular Septal (Endocardial Cushion) Defect
Characterized by a drastically enlarged RA and small RV which causes small LA and LV
-Associated w/ Lithium exposure in utero
Ebstein’s anomaly
Tricuspid valve never opens and there is an ASD with
Tricuspid Atresia
Characterized by absence of tricuspid orifice, ASD, hypoplastic RV, and VSD
Tricuspid Atresia
Thought to be caused by unequal division of AV canal
Tricuspid Atresia
Immediately managed by maintaining a PDA, placement of Blalock-Taussig shunt
Tricuspid Atresia
3-6 months after tricuspid atresia
-The second stage of treatment
Bidirectional Glenn Procedure
Then, at 3-5 years of age, we perform a
-Third stage of tricuspid atresia treatment
Fontan Procedure
Infants present with cyanosis and signs/symptoms of heart failure
-Corrective surgery should be performed as soon as possible
Total Anomalous Return
Linked to cardiac neural crest cells
-Always associated with VSD due to underdevelopment on distal pulmonary infundibulum
Truncus Arteriosus
30% of truncus arteriosus cases involve right sided
Aortic arch
Truncus Arteriosus often presents as part of
DiGeorge Syndrome
During the first few days of life, mild to moderate cyanosis may be the only sign. However, as pulmonary vascular resistance falls, symptoms of HF and pulmonary congestion develop
Truncus Arteriosus
Treatment is surgical and involves closing the VSD and attaching pulmonary arteries through a conduit to the right ventricle
Truncus Arteriosus
