Congenital Heart Defects- Bricks + Lecture Flashcards
The most common congenital heart defect is _
The most common congenital heart defect is ventricular septal defect
Three CHDs associated with Down syndrome
- Atrial septal defect
- AV septal defect (endocardial cushion defect)
- Ventricular septal defect
Two CHDs associated with Turner syndrome
- Bicuspid aortic valve defect
- Coarctation of the aorta
Two CHDs associated with 22q11 syndrome
- Tetralogy of fallot
- Truncus arteriosus
The foramen ovale in the fetus connects the _ and _
The foramen ovale in the fetus connects the right and left atria
The ductus arteriosus in the fetus connects the _ and _
The ductus arteriosus in the fetus connects the pulmonary artery and aorta
The three cardinal signs of CHD are _ , _ , and _
The three cardinal signs of CHD are heart failure , cyanosis , and clubbing
How do CHDs contribute to the development of heart failure?
In CHDs, the ventricular wall adapts to the high blood pressure via hypertrophy or hyperplasia –> dilation leads to HF
Chronic hypoxemia from cyanotic heart defects can present with _
Chronic hypoxemia from cyanotic heart defects can present with clubbing
Left-to-right shunts are (cyanotic/ acyanotic)
Left-to-right shunts are acyanotic
_ is a complication in which a long standing acyanotic left-to-right shunt is reversed to a cyanotic right-to-left shunt
Eisenmenger syndrome is a complication in which a long standing acyanotic left-to-right shunt is reversed to a cyanotic right-to-left shunt
ASDs, VSDs, PDAs are simply openings and they can cause shunts in either direction; _ is most common/expected
ASDs, VSDs, PDAs are simply openings and they can cause shunts in either direction; left-to-right shunting is most common/expected
How can we end up with a right-to-left shunt?
In order to develop a right-to-left shunt, we must have an increase in right heart pressure –> can be caused by the pulmonary artery thickening its wall –> pulmonary hypertension –> right ventricle thickens –> shunt reverses
Five types of CHD present with right-to-left shunts initially:
- Truncus arteriosus
- Transposition of the great arteries
- Tricuspid atresia
- Tetralogy of Fallot
- Total anomalous pulmonary venous return (TAPVR)
The right-to-left shunts that exist at birth are often established due to _
The right-to-left shunts that exist at birth are often established due to fetal hemodynamics; in utero the right heart has higher pressure than the left; normally switches at birth
Obstructive CHDs are (cyanotic/acyanotic)
Obstructive CHDs are acyanotic
About 70% of all ASDs are _ defects
About 70% of all ASDs are secundum defects
ASDs most commonly present around _
ASDs most commonly present around adolescence or adulthood
* Can present with symptoms of heart failure
Two classic physical exam findings of an ASD are _ and _
Two classic physical exam findings of an ASD are prominent systolic impulse along the lower left sternal border and fixed wide split S2
Pulmonic valve murmurs can be heard in severe ASD and sound like _
Pulmonic valve murmurs can be heard in severe ASD and sound like systolic murmur in the second left intercostal space radiating to the back
Severe VSDs in infants can present around _ months of age with significant symptoms of _
Severe VSDs in infants can present around 2-3 months of age with significant symptoms of heart failure
* Sx: tachypnea, poor feeding, weight gain, frequent lower respiratory tract infections
Large VSDs in children and adult present with _ symptoms
Large VSDs in children and adult present with dyspnea and fatigue on exertion
VSDs result from the improper development of _
VSDs result from the improper development of IV septum
The majority of VSDs result from the improper development of the (membranous/ muscular) portion of the IV septum
The majority of VSDs result from the improper development of the membranous portion of the IV septum
Two problems presented from VSD
- Less blood is getting ejected into the systemic circulation; this heart is having to work harder
- RV and pulmonary circulation are receiving more blood than normal –> remodeling –> right heart failure
The most common complication of VSD is _
The most common complication of VSD is right heart failure
A VSD can be diagnosed via _ findings on physcial exam
A VSD can be diagnosed via harsh holosystolic murmur at the left lower sternal boarder (LLSB) findings on physcial exam
* Best heard in the tricuspid area
(Smaller/ larger) defects have louder, higher pitched murmurs
Smaller defects have louder, higher pitched murmurs
* The turbulent flow across the defect is greater
* Sometimes flow is so strong that a palpable thrill can be noticed over the left sternal boarder
Common risk factors of patent ductus arteriosus (PDA)
PDA risk factors:
* Maternal rubella infection during pregnancy
* High altitude birth
* Premature infants
How do patients with PDA normally present?
- Severe (large) PDAs present at birth with more severe symptoms
- Less severe PDAs are often asymptomatic at birth and present later in childhood with fatigue and exertional dyspnea
The ductus arteriosus arises from the _ and connects the _ to the _
The ductus arteriosus arises from the left sixth aortic arch artery and connects the pulmonary arteries to the descending aorta
* In babies, the DA shunts most of the blood ejected from the RV directly into the aorta… bypassing the lungs
* If present after birth it shunts blood from aorta –> pulmonary artery
The ductus arteriosus normally closes after birth within _ hours when _ pressures change
The ductus arteriosus normally closes after birth within 15-30 hours hours when pulmonary vascular resistance decreases
Closure of the ductus arteriosus is also related to the decline of _
Closure of the ductus arteriosus is also related to the decline of prostaglandin E1
Chronic volume overload from ductus arteriosus can lead to (right/ left) heart failure
Chronic volume overload from ductus arteriosus can lead to left heart failure
* The left side of the heart is not efficient at pumping blood because some of it is going into the pulmonary circulation –> hypertrophy
Describe the development of Eisenmenger Syndrome in the context of PDA
PDA –> Chronic volume overload of pulmonary circulation –> thickening of pulmonary vasculature –> increases resistance –> resistance becomes greater than descending aorta
PDA patients with Eisenmenger syndrome can be diagnosed by the presence of _
PDA patients with Eisenmenger syndrome can be diagnosed by the presence of differential cyanosis
* Only the lower extremities appear blue
* Deoxygenated blood enters the aorta after the subclavian artery branches off so upper extremities are supplied by oxygen
The classic physical exam finding associated with a PDA is _
The classic physical exam finding associated with a PDA is continuous, machine-like flow murmur best heard over the left subclavian region
Premature infants with PDA are initially managed medically with the use of _
Premature infants with PDA are initially managed medically with the use of COX inhibitors (ie Indomethacin) –> induce the closure by blocking the production of PGE1
* COX inhibitors are usually not effective at closing PDAs for infants born at term
Tetralogy of Fallot
Tetralogy of Fallot is the name for the combination of four specific CHDs
1. Pulmonary valve stenosis
2. RV hypertrophy
3. VSD
4. Overriding aorta
An overriding aorta _
An overriding aorta emerges from both ventricles
* Therefore it receives blood from both ventricles
The primary significant defect in TOF is _
The primary significant defect in TOF is pulmonary valve stenosis
A “tet spell” is an _
A “tet spell” is an episode of cyanosis, rapid breathing, and irritability
* Can result from agitation, feeding, illness
* Tet spells are unique to tetralogy of fallot!
Tetralogy of Fallot is thought to be due to _
Tetralogy of Fallot is thought to be due to malalignment of the conal septum –> causes the outflow tract to stenose –> aorta to override –> VSD to persist
* The aorta overrides from abnormal development of the spiral septum
Tet spells are caused by _
Tet spells are caused by systemic arteries dilating during exertion –> lowering systemic resistance –> lowers resistance in the LV –> causes more morement from R –> L –> tet spell
* Squatting helps because it increases SVR
What does TOF look like on a chest x-ray?
Boot-shaped heart appears on chest x-ray
Tricuspid atresia is _
Tricuspid atresia is absense of a functional tricuspid valve
* This means no direct connection between the right atrium and right ventricle
* This is incompatible with life unless there is another defect present to compensate
Truncus arteriosus is the failure of the development of the truncus due to failed _
Truncus arteriosus is the failure of the development of the truncus due to failed migration of neural crest cells
* Normally this divides to give rise to the pulmonary valve and the aortic valve (pulmonary trunk and aorta)
* In TA, the septum that is supposed to divide the two never forms
Transposition of the great arteries occurs when _
Transposition of the great arteries occurs when aorta and pulmonary artery are switched
* This is usually caught at birth because infant will be cyanotic
The chest x-ray on a patient with transposition is characterized by _
The chest x-ray on a patient with transposition is characterized by left ventricular enlargement with described as “egg-on-a-string”
Total anomalous pulmonary venous return is a defect in which _
Total anomalous pulmonary venous return is a defect in which pulmonary veins drain into the right heart
* Oxygenated blood can only enter the systemic circulation via an abnormal R –> L shunt via ASD or PDA
Coarctation of the aorta is _
Coarctation of the aorta is narrowing of the aorta lumen
The coarctation of the aorta is most commonly located at the _
The coarctation of the aorta is most commonly located at the descending aorta, just distal to the left subclavian artery and near the attachment of the ligamentum arteriosum
Atrial septal defects can occur anywhere along the septum; however, the most common location is the _
Atrial septal defects can occur anywhere along the septum; however, the most common location is the ostium secundum
* Can also have ostium primum defects which affect the endocardial cushions
* Sinus venosus defects which connect the SVC and RA
* Patent foramen ovale (PFO) is another ASD
Where do we listen for physiologic or pathologic splitting?
Splitting can only be heart over the pulmonic region because this is the only location where the pulmonary valve closure can be heart; aortic closure can be heart in all locations
* If you hear a pulmonic closure in other locations it is pathologic- either from pulmonary hypertension or ASD
Describe what we would find when auscultating ASD
ASD will have persistent splitting of S2 meaning it can be heard through inspiration and expiration
* This is a fixed split S2
* This occurs because of the increased amount of blood flow to the right side of the heart through the defect, causing the pulmonary valve to close later since so much blood needs to flow through
ASD murmurs will be described as a 2/6 or 3/6 low-pitched _ murmur best heard over the _
ASD murmurs will be described as a 2/6 or 3/6 low-pitched systolic ejection murmur best heard over the upper left sternal border
* Often ASD will not produce a murmur since the pressure gradient between the two atria is not significant enough for turbulent flow
Pulmonic valve murmurs (like in ASD) are heard because _
Pulmonic valve murmurs (like in ASD) are heard because increased blood flow on the right side of the heart
Most VSD come from a defect in the _
Most VSD come from a defect in the membranous IV septum
* They can sometimes be adjacent to the semilunar or AV valves
* Many babies born with small VSD will have natural closure after a couple of months
Describe the ausculatory findings of VSD
VSD will have normal S1 and S2 but will present with 4/6 harsh systolic murmur heard maximally at the LLSB
* Can be heard throughout
Patent ductus arteriosus may result in complications including _
Patent ductus arteriosus may result in complications including
* Pulmonary overcirculation
* LA and LV overload
* Potential LV dysfunction
Extra blood is going into the pulmonary trunk –> lungs –> LA –> get left sided overload
A PDA will present with _ ausculatory findings
A PDA will present with normal S1 and S2 and a 3/6 continuous “machine-like” murmur
The continuous, machine-like murmur of a PDA is best heard over the _
The continuous, machine-like murmur of a PDA is best heard over the left subclavicular area
Patient comes in tachypneic, with mild substernal retractions; there are crackles heard in the lungs and a 3/6 continuous “machine-like murmur” heard at the left subclavicular area; pulses are 2+ distally and extremities are warm
Patent ductus arteriosus
Most cases of congenital aortic stenosis are associated with an aortic valve that has _
Most cases of congenital aortic stenosis are associated with an aortic valve that has two valve leaflets
* 1% of the general population has this, unknowingly
Aortic stenosis, either due to congenital abnormality or from other stenosis will require that the _ have higher pressure
Aortic stenosis, either due to congenital abnormality or from other stenosis will require that the left ventricle have higher pressure
* High velocity of blood through the proximal aorta may also cause damage
Congenital pulmonic stenosis is far less common than aortic stenosis; it is caused by _
Congenital pulmonic stenosis is far less common than aortic stenosis; it is caused by abnormal formation or regression of subendocardial mesenchymal tissue
Coarctation of the aorta is a narrowing of the aorta either just before or after the _
Coarctation of the aorta is a narrowing of the aorta either just before or after the ductus arteriosus / ligamentum arteriosum
* Most infantile forms are pre-ductal
* Most adult forms are post-ductal (PDA may remain open)
Down syndrome is associated with _
Down syndrome is associated with septal defects
* ASD
* VSD
* AV septal defects (endocardial cushion defect)
In transposition of the great vessels, the aorta arises from the _ and the pulmonary trunk arises from the _
In transposition of the great vessels, the aorta arises from the right ventricle and the pulmonary trunk arises from the left ventricle
Transposition of the great arteries is caused by _
Transposition of the great arteries is caused by failure of the aorticopulmonary septum to spiral in normal fashion
Transposition of the great arteries is not compatible with life unless we have another CHD somewhere; we can give infants _ medication to help
Transposition of the great arteries is not compatible with life unless we have another CHD somewhere; we can give infants Prostaglandin E1 to keep the PDA open
The most common cyanotic congenital heart disease (although not the most frequenty diagnosed in neonates) is _
The most common cyanotic congenital heart disease (although not the most frequenty diagnosed in neonates) is tetralogy of fallot
Name the four components of tetralogy of fallot
Tetralogy of Fallot:
1. VSD
2. Pulmonic stenosis
3. Aorta over-rides VSD
4. Right ventricular hypertrophy
To resolve tet spells we can put babies in _ position; this alleviates their cyanosis by _
To resolve tet spells we can put babies in squatting position; this alleviates their cyanosis by increasing SVR and increasing resistance of the aorta –> tries to push more blood through the pulmonary valve instead
Eisenmenger’s syndrome is shunt reversal (now right –> left) that can result from uncorrected VSD, ASD, PDA due to _
Eisenmenger’s syndrome is shunt reversal (now right –> left) that can result from uncorrected VSD, ASD, PDA due to progressive pulmonary hypertension / vessel thickening / reduced O2 vasodilation responsiveness
* Patient now presents with cyanosis, clubbing, polycythemia
