Cardiac -- Congenital

Acyanotic + increased pulmonary blood flow = L to R shunt
- Atrial level: Sinus venosus defect (associated with PAPVR), ASD
- VSD
- PDA
- Endocardial cushion defect: failure of complete development of both the atrial and ventricular septa as well as maldevelopment of mitral and tricuspid valves. Strong association with Down syndrome.
2. L to R shunt shunt results in increased blood return to the left heart.
- In ASD, the LA is not enlarged as it decompresses into a low pressure RA.
- LA is enlarged in VSD and PDA as it empties into a higher pressure LV.
- Aortic knob is small in size in VSD; Aortic knob is larger in PDA.

1. Untreated L to R shunts result in pulmonary HTN.
2. Adulthood during which they present as pulm HTN.
3. There are 4 types of ASD:
- Sinus venosus defect – associated with PAPVR (right upper pulmonary vein drains into SVC); occurs superiorly in atrial septum near SVC insertion.
- PFO
- Ostium secundum – MC
- Ostium primum – AKA endocardial cushion defect: occurs inferiorly; may involve atrial and ventricular portions of the septum.
4. Amplatzer device is inserted percutaneously and is used to close septal defects.

1.
- Ostium secundum: most common type of ASD.
- Ostium primum ASD: associated with endocardial cushion defects.
- Sinus venous ASD: located at the entrance of the superior vena cava (SVC) and is always associated with partial anomalous pulmonary venous return. The right upper pulmonary vein drains into the SVC.
2. The high pressure in the left atrium relative to the right atrium causes flow across the defect and increased pulmonary circulation. Moderate to large ASD will demonstrate right atrial and right ventricular enlargement with increased pulmonary vasculature. RV enlargement is detectable by abnormal filling of the retrosternal air space on the lateral film.
3. The left atrium is not enlarged in ASD as it decompresses into the RA through the septal defect. The left atrium is enlarged in VSD and patent ductus arteriosus.
4. The pulmonary vessels are enlarged and detectable in the lung periphery. If the diameter of the right descending pulmonary artery is larger than the trachea, think increased pulmonary vascularity.

1.
- Hypoplasia or absence of the left ventricle with an atretic aortic and mitral valve.
- Because of the atretic aortic and mitral valves, there is a large interatrial shunt (left-to-right shunt) and patent ductus arteriosus (right-to-left shunt) to sustain life.
- Echocardiogram demonstrates a small left ventricle, small aorta, enlarged right ventricle and enlarged pulmonary artery.
- blood flow to the coronary arteries is from the atretic ascending aorta.

2. Patients present with cardiovascular collapse when the ductus arteriosus begins to close, cutting off shunted blood from the pulmonary artery.

1. Transposition of the great vessels
2. Truncus arteriosus
3. Total anomalous pulmonary venous return
4. Single ventricle

1. TOF (normal heart size)
2. Ebstein anomaly (enlarged heart)
3. Pulmonic atresia (enlarged heart)
4. Tricuspid atresia (enlarged heart).

D= dextroposition
Aorta is slightly to the right of the pulmonary artery.

1. Aorta is connected to the right ventricle and thus located anterior to the pulmonary artery. The pulmonary artery is connected to the left ventricle. There must be bidirectional communication b/w the circulations (via a ASD, VSD, or patent ductus arteriosus) to sustain life.
2. Patent foramen ovale. Increased pressures from the RV are transmitted into the RA which prevents closure of foramen ovale. Patients are also given prostaglandins to prevent closure of PDA.
3.
- Egg on a string appearance: 2/2 narrowing of the superior mediastinum due to hypoplastic thymus. Enlarged RA and RV.
- Poorly seen aortic arch and pulmonary artery 2/2 abnormal ventricular connections.
4. Jatene arterial switch procedure in which aorta and PA are switched to their normal ventricular connections.

D-transposition of the great vessels is characterized by cyanosis at birth (D = Death). The chest radiograph shows a characteristic "egg-on-a-string" sign in addition to increased pulmonary vascularity. Atrioventricular concordance and ventriculoarterial discordance is seen. Treatment includes giving prostaglandin E1 to keep the ductus aneriosus open, an atrial septostomy, and eventually an arterial switch procedure (Jatene).

Incorrect: In L-transposition, there is both atrioventricular and ventriculoarterial discordance. In this case, there is only ventriculoarterial discordance. L-transposition does not lead to cyanosis.

Levo-transposition of the great vessels (L-TGA) is characterized by atrioventricular discordance and ventriculoarterial discordance and is also called "congenitally corrected" TGA. You can think of this as "2 wrongs make a right." Another way to remember how to distinguish between L-TGA and dextro-transposition of the great vessels (D-TGA) is that L = life (can survive without correction) and D = death (fatal without correction). In TGA, you can recognize the right ventricle by its increased trabeculations, moderator band, and chordal attachments to the septum, and you can recognize the left ventricle by its smooth wall and lack of chordal attachments to septum. In L-TGA, the pulmonary artery arises anteriorly from the left ventricle while the aorta arises posteriorly from the right ventricle. Associated lesions include ventricular septal defects (60-70%), right ventricular outflow tract obstruction (30-50%), and systemic atrioventricular valve abnormalities (90%).

most common anomaly of great vessel position in which the aorta is located anteriorly and arises from the right ventricle. the pulmonary artery arises posteriorly from the left ventricle.
- a parallel relationship of the proximal aorta to the pulmonary trunk indicates TGA.
- the ventricles are in their Normal position in D-TGV, with the aorta on the right of the pulmonary artery.
- in corrected transposition, or L-TGV, the ventricles are also reversed, so that the aorta is located to the left of the pulmonary artery.

1. Coarctation refers to congenital narrowing of the aorta that can either be focal or diffuse.
- Focal type: located at the level of the ductus; can also be acquired from rubella infection, turner's syndrome, and neurofibromatosis.
- Diffuse type: most commonly seen in children; involves a large segment that spans from the innominate to the ductus arteriosus. May be so severe that it results in an interrupted aortic arch.
2.
- "Figure of 3" sign made up of an enlarged ascending aorta, followed by the narrowing which forms the waist of the 3, and then post-stenotic dilation
- reverse 3 configuration refers to pattern of narrowing of the esophagus seen on an esophagram.
- LV dilation/hypertrophy
- Rib notching
3. On the lateral view, the LV comprises the lower half of the posterior cardiac border. The posterior border ought to cross the lVC 2 cm above the diaphragm. An intersection below this point suggests LV enlargement.
4. Pseudo coarctation refers to a tortuous aortic arch which gives the appearance of a coarctation. There is no gradient across the presumed stenosis and thus no collateral vessels are seen.

Likely associated with contraction of smooth muscle at the time of closure of ductus arteriosus.

1. Decreased pulmonary vascularity and a severely enlarged heart (box-shaped) due to right atrial enlargement.
2. Partial atrialization of the right ventricle and tricuspid redundancy resulting in a large RA, small RV, and an insufficient tricuspid valve. There is always an associated patent foramen ovale (PFO) or atrial septal defect (ASD). Blood entering the small poorly contracting ventricle exits either through the pulmonary artery or back through the insufficient tricuspid valve. Blood begins to shunt though the PFO or ASD, causing cyanosis. apical displacement of the septal leaflet of the tricuspid valve straight arrow. The anterior leaflet originates normally at the atrioventricular groove level
Ebstein anomaly is associated with maternal lithium use.
3. Pulmonary atresia with an intact ventricular septum can have an identical appearance to ebstein anomaly. There is massive right atriomegaly from tricuspid insufficiency.

1. Tricuspid atresia refers to complete absence of the tricuspid valve with no direct connection from the right atrim to the right ventricle.
2. In order to sustain life, a patent foramen ovale or atrial septal defect with either a ventricular septal defect (VSD) or patent ductus arteriosus (PDA) must be present.
Blood goes from RA - LA - LV- VSD - RV. Alternatively, blood goes from RA - LA - LV - Aorta - PDA - PA.
3. Decreased pulmonary vascularity, left ventricular hypertrophy, small pulmonary artery.

1. Endocardial cushions contribute to the formation of the lower atrial setpum, upper portion of the ventricular septum, AV septa, tricuspid, and mitral valves.
2. 40% of pts with Down syndrome have endocardial cushion defect.
3. On angiogram, a 30 degree anterior oblique demonstrates the classic gooseneck deformity.

1. Tetralogy of fallot.
2.
- right ventricular outflow obstruction: usually occurs at the level of the infundibulum.
- right ventricular hypertrophy
- overriding aorta: receives blood flow from both ventricles
- ventricular septal defect (VSD)
right-to-Ieft shunt.
To summarize, a small RV outflow tract increases RV pressure to where it overcomes the LV pressure and a right-to-Ieft shunt develops with non-oxygenated blood exiting the aorta. cyanosis would improve with the child in the fetal (squatting) position as systemic resistance increases, thereby reversing the shunt and forcing blood through the pulmonary artery.
3. Heart is normal in size and has a typical "boot" or "clog" shape with uplifting of the ventricular apex due to right ventricular hypertrophy. The main pulmonary artery is not visualized.

right sided aortic arch in 25%.

1. Supracardiac, cardiac, and infracardiac.
Type 1:
- Snowman appearance of the heart due to left vertical vein resulting in mediastinal widening.
- heart is enlarged
- pulmonary congestion

Type 2: 
- intracardiac; 
- non- obstructive flow, therefore, no pulmonary edema.
- TAPVR is to the coronary sinus

Type3: 
- infra cardiac 
- heart size is normal with severe pulmonary edema.
- pulmonary venous return is to the IVC, portal vein, ductus venosus; 
- TAPVR is below the diaphragm via the esophageal hiatus where there is obstruction of the vein resulting in pulmonary edema.

2. Supracardiac connections:
- most common
- "snowman appearance" with the upper right side formed by a dilated SVC and the left side formed by the vertical vein. The vertical vein draines into the left innominate vein.
3. The cardiac connection is either to the coronary sinus or RA.
4. Infracardiac connection:
- dives below the diaphragm and joins with either the portal system, hepatic veins, or IVC.
5. Both the systemic venous and pulmonary circulations drain to the right atrium. The elevated pressure within the right atrium keeps the foramen ovale patent with resultant right to left shunting and cyanosis. Enlargement of the RA and RV follow.

1. Tetralogy of fallot
2. Truncus arteriosus

1.
- Failure of the primary truncus to divide into the pulmonary artery and aorta.
- One large vessel supplies the coronary, systemic, and pulmonary circulations.
- A ventricular septal defect is always present with blood shunting from the right ventricle to the left ventricle. In the truncus, there is left to right shunt with blood shunted into the pulmonary artery.
2. 40% are associated with a right sided aortic arch.

1. Bicuspid aortic valve (more common than VSD).
2. Valvular, supravalvular, subvalvular (membranous or muscular.
3.
- LV hypertrophy and poststenotic dilatation of the aorta.
- Thickened valves with poor motility. Turbulent flow through a stenotic valve
- NOTE: The ascending aorta should not be border-forming before 10 years of age. Therefore, if seen on the frontal radiograph raise the question of aortic stenosis.
- Aortic valve calcifications in a patient younger than 50 years of age. If aortic valve calcifications are seen in a pt younger than 40 years of age, raise concern for unicuspid aortic valve.
- The aortic valve is bicuspid with a single commissure. Only 2 leaflets are present with congenital fusion of the right and left cusps that are joined inferiorly by a thickened raphe, which is seen is about 50% of cases of congential bicuspid aortic valve.
4. Idiopathic infantile hypercalcemia (William syndrome) -- mental retardation, elfin facies (friendly demeanor), supravalvular aortic stenosis, and pulmonic stenosis.
5.
- Membranous form is more common -- look for a discrete fibrous membrane or diaphragm in a subvalvular location.
- Muscular subaortic stenosis results in more diffuse obstruction resulting in a tunnel shaped LV outflow tract. This type has a significant female predominance.
6.
Acquired: senile (degenerative), rheumatic heart disease, infectious endocarditis.
Congenital: bicuspid aortic valve, supra valvular and sub valvular stenosis.

1. Right sided aortic arch can be associated with an aberrant left subclavian artery or mirror imaging branching in which the first branch from the aorta is the left brachiocephalic artery followed by the right internal carotid and right subclavian artery.
2. Mirror image branching is associated with a high risk of congenital heart disease (98%)

3. Right sided aortic arch with an aberrant left subclavian artery and the ligamentum arteriosum forms a vascular ring.

1. ASD, particularly when the PAPVR drains the right lung to the SVC.
2. Right upper lung draining into the SVC.
3. Scimitar syndrome

The most common partial anomalous venous return is when the left superior pulmonary vein drains into the subclavian vein, which may produce an aortic nipple (not seen in this case).

- Aberrant origin of the left pulmonary artery from the right pulmonary artery.
- Associated with complete tracheal rings ("napkin ring" cartilage).
- Hypoplasia of the distal trachea or right main bronchus.
- Looks for hyperlucent right lung and deviation of the trachea to the left with narrowing of the distal tracheal air column.
- barium esophagogram shows anterior indentation of the esophagus.