Congenital Cardiovascular Disease

Question 1

Congenital heart defects are problems with the heart’s structure that are present at birth, these include:

Answer 1

• The interior walls of the heart
• The valves inside the heart
• The arteries and veins that carry blood to the heart or the body

Question 2

Congenital heart disease is often divided into 2 types:

Answer 2

non-cyanotic and cyanotic (blue skin colour caused by

a lack of oxygen)

Question 3

Cyanotic:

Answer 3

• Cyanotic:
• Tetralogy of Fallot
• Total anomalous pulmonary venous return
• Transposition of the great vessels
• Tricuspid atresia
• Truncus arteriosus
• Hypoplastic left heart
• Pulmonary atresia
• Ebstein’s anomaly (severe)

Question 4

• Non-cyanotic:

Answer 4

• Ventricular septal defect (VSD)
• Atrial septal defect (ASD)
• Patent ductus arteriosus (PDA)
• Coarctation of the aorta
• Pulmonary stenosis
• Aortic stenosis
• Atrioventricular canal (endocardial cushion defect)
• Ebstein’s anomaly (mild)

Question 5

Extracardiac anomalies in CHD

Answer 5

• 25% of infants seen during the first year of life for significant cardiac disease
• most frequent ECA are in the musculoskeletal system or associated with a specific syndrome
• increases the mortality in infants with CHD

Question 6

Symptoms / signs of heart failure in infants with CHD

Answer 6

• Cyanosis
(> 5g/dl deoxyhaemoglobin)
• Rapid breathing (Tachypnoea)
• Extra work of breathing
• Grunting

• Tachycardia
• Poor blood circulation
• Fatigue (Poor feeding)
• Faltering growth
• Sweating
• Enlarged Liver (Hepatomegaly) • Murmurs

Question 7

Complications of CHD

Answer 7

• Faltering growth (previously referred to as “failure to thrive”)
• Paradoxical embolus (venous to arterial)
• Bacterial endocarditis
• Pulmonary hypertension
• Polycythaemia
• Haemoptysis
• Arrhythmias

Question 8

Ventricular septal defect (VSD)

Answer 8

• 39% of infants with CHD

- small (no problems and can close on their own), medium (more likely to require treatment) or large

Question 9

Large VSDs

Answer 9

allow a lot of blood to flow from the left ventricle to the right ventricle. As a result, the left side of the heart must work harder than normal. Extra blood flow increases blood pressure in the right side of the heart and the lungs

Question 10

consequences of a large VSD

Answer 10

The heart’s extra workload can cause heart failure and poor growth. If the hole isn’t closed, high blood pressure can scar the arteries in the lungs leading to the dreaded complication of Pulmonary Hypertension and irreversible damage leading to shunt reversal and Eisenmenger’s Syndrome

Question 11

Atrial septal defect (ASD)

Answer 11

• 10% of infants with CHD
• small (only a little blood to leak from one atrium to the other, don’t effect how the heart works and don’t need treatment), medium or large

Question 12

medium and large ASDs

Answer 12

they allow more blood to leak from one atrium to the other and are less likely to close on their own. can be repaired during a catheter procedure or open-heart surgery

Question 13

long term effects of medium and large ASDs

Answer 13

If there is a longstanding significant left to right shunt through the ASD the increased blood flow through the lungs can scar the arteries in the lungs leading to the dreaded complication of Pulmonary Hypertension / shunt reversal and Eisenmenger’s Syndrome

Question 14

Patent Ductus Arteriosus (PDA)

Answer 14

• 10% of infants with CHD
• persistent communication between the descending thoracic aorta and the pulmonary artery that results from failure of normal physiological closure of the foetal ductus

Question 15

treatment of PDA

Answer 15

if significant respiratory distress or impaired systemic oxygen delivery is present, therapy is usually prudent
- • Intravenous indomethacin or ibuprofen is frequently effective in closing a PDA if it is administered in the first 10-14 days of life.
• Other options are catheter closure and surgical ligation.

Question 16

Patent Foramen Ovale (PFO)

Answer 16

• Immediately after birth, pressure in the right side of the heart and pulmonary vascular resistance diminish abruptly as the pulmonary alveoli fill.
• This, together with greater pressure in the left atrium due to increased venous return, produces functional closure of the foramen ovale which in 75% of people closes structurally in infancy.
• PFO is a flaplike opening between the atrial septa primum and secundum at the location of the fossa ovalis that persists after age 1 year.

Question 17

PFO

Answer 17

• 25% of infants
  • It is considered a normal condition rather than a form of Congenital Heart Disease.
  • Although a PFO is an opening between the right and left atria it is not considered an Atrial Septal Defect because no septal tissue is missing and there is no significant shunting.
  • Rarely PFO can be the culprit in paradoxical embolic events.

Question 18

Coarctation of the aorta (CoA)

Answer 18

• 7% of infants with CHD
• may occur as an isolated defect or in association with various other lesions, most commonly bicuspid aortic valve and VSD.

Question 19

The classic CoA is located in

Answer 19

the thoracic aorta distal to the origin of the left subclavian artery at about the level of the ductal structure.
• CoA imposes significant afterload on the left ventricle, which results in increased wall stress and compensatory ventricular hypertrophy.
• The afterload may be imposed acutely, as occurs following closure of the ductus arteriosus in neonates with severe coarctation.
• These infants may rapidly develop congestive heart failure and shock.

Question 20

Clinical presentation of Coarctation of the Aorta

Answer 20

• Patients may be asymptomatic in a setting of a non-severe stenosis.
• Children and adults can present with angina pectoris and leg claudication.
• On clinical examination, diminished femoral pulses and differential blood pressure between upper and lower extremities may be noted.

Question 21

Treatment and prognosis of Coarctation of the Aorta.

Answer 21

• The urgency of treatment depends on the presence of congestive cardiac failure.
• This is usually the case in severe coarctations found in infancy.
• In less severe cases, elective treatment when the child is older (typically ~2 years of age) is preferred .
- primary surgical repair with excision of the coarctation and end-to-end
anastomosis, or balloon angioplasty

Question 22

Subclavian flap repair

Answer 22

Treatment of
Coarctation of the Aorta:
a common surgical technique used, where the origin and proximal left subclavian artery is excised, opened up and sutured onto the aorta.
• If the subclavian is ligated, it is usually anastomosed onto the left common carotid artery.

Question 23

Atresia

Answer 23

if a valve doesn’t form correctly and lacks a hole for blood to pass through. Atresia of a valve generally results in more complex congenital heart disease.

Question 24

Stenosis

Answer 24

if the flaps of a valve thicken, stiffen, or fuse together. As a result, the valve cannot fully open. Thus, the heart has to work harder to pump blood through the valve.

Question 25

Regurgitation

Answer 25

if a valve doesn’t close tightly. As a result, blood leaks back through the valve.

Question 26

Pulmonary valve stenosis

Answer 26

a narrowing of the pulmonary valve

• can range from mild to severe.
• Most children who have this defect have no signs or symptoms other than a heart murmur. Treatment isn’t needed if the stenosis is mild

Question 27

In babies who have severe pulmonary valve stenosis,

Answer 27

the right ventricle can get very overworked trying to pump blood to the pulmonary artery. These infants may have signs and symptoms of heart failure
Severe pulmonary valve stenosis is treated with a catheter procedure.

Question 28

Aortic valve stenosis

Answer 28

results from minor to severe degrees of aortic valve maldevelopment

causes mild to severe obstruction of the left ventricular outflow that may be associated with other left heart obstructive lesions, varying degrees of left heart hypoplasia, or extracardiac malformations, including genetic disorders.

Question 29

Adult patients with bicuspid aortic valves may develop

Answer 29

significant stenosis or insufficiency after the valve becomes calcified in the fourth, fifth, or sixth decade of life

Question 30

Aortic valve stenosis treatment

Answer 30

Balloon aortic valvuloplasty is considered the initial treatment of choice in pediatric patients with congenital aortic valve stenosis

• Surgical repair or replacement of an aortic valve is primarily reserved for patients in whom balloon valvuloplasty has failed with severe stenosis or have significant valve insufficiency in association with progressive left ventricular dilation or deterioration of left ventricular systolic function

Question 31

Tetralogy of Fallot (TOF)

Answer 31

combination of four defects:
• Pulmonary valve stenosis.
• A large VSD.
• An overriding aorta.
• Right ventricular hypertrophy

Question 32

An overriding aorta

Answer 32

The aorta is located between the left and right ventricles, directly over the VSD. As a result, oxygen-poor blood from the right ventricle can flow directly into the aorta instead of into the pulmonary artery

Question 33

TOF stats

Answer 33

• 1 in 2,000
  newborns.
  • Males and females are affected equally.
  • It is the most common complex congenital heart defect.

Question 34

Tet spells

Answer 34

In some children with unrepaired tetralogy of Fallot sudden episodes of profound cyanosis and hypoxia (tet spell) may occur, which may be lethal
• A spell may be triggered by any event that slightly decreases oxygen saturation (eg, crying, defecating) or that suddenly decreases systemic vascular resistance (eg, playing, kicking legs when awakening) or by sudden onset of tachycardia or hypovolemia

Question 35

Palliative surgery for TOF

Answer 35

forming a side to end anastomosis between
the subclavian artery and the pulmonary artery.
This redirected a large portion of the partially oxygenated blood leaving the heart for the body into the lungs, increasing flow through the pulmonary circuit, and greatly relieving symptoms in patients.

Question 36

Surgery for TOF

Answer 36

Total repair on infants has had success from 1981.
• Tetralogy of Fallot must be repaired with open-heart surgery, either soon after birth or later in infancy.
• The timing of the surgery will depend on how narrow the pulmonary artery is.

Question 37

Hypoplastic Left Heart Syndrome (HLHS)

Answer 37

• Hypoplastic left heart syndrome occurs in up to four out of every 10,000 live births.
• The syndrome comprises 8 percent of all cases of congenital heart disease.
• It is one of the top three heart abnormalities to cause problems in the newborn.
• HLHS occurs slightly more often in boys (55% -70%) than in girls.

Question 38

Hypoplastic Left Heart Syndrome (HLHS) pathology

Answer 38

• Foetuses are nourished by oxygen-rich blood from their mothers so they don’t breathe and don’t use their lungs.
• Babies with hypoplastic left heart syndrome may seem normal at birth because the patent ductus arteriosus is still open, allowing blood to continue circulating directly into the aorta and out to the rest of the body.
• Once the ductus closes a few days after birth, blood flows to the lungs and then to the left side of the heart where it is blocked and can’t circulate through the rest of the body. It is at
this time that these babies show symptoms

Question 39

How is Hypoplastic Left Heart Syndrome treated?

Answer 39

• HLHS is treated with surgery. This can involve either a series of 3 heart surgeries or, less commonly, heart transplantation.
• In some instances, a hybrid procedure involving a combination of surgery and cardiac catheterization may be used to treat the child in place of the first in a series of 3 surgeries.

Question 40

Balloon Atrial Septostomy in initial treatment of HLHS.

Answer 40

• This may be done to help until a complete repair can be done. During this procedure, a catheter (thin, flexible tube) with a balloon on the end is used.
• It is guided through a blood vessel into the heart. The balloon is inflated to widen the foramen ovale.
• Sometimes, a stent may be placed to keep the hole open. This allows more blood to mix freely between the atria.
• More oxygenated blood can then reach the body.

Question 41

Transposition of The Great Arteries.

Answer 41

• In this situation, the pulmonary arteries are supplied by the left ventricle, and the aorta by the right ventricle.
• This, of course, is the opposite of the normal arrangement.
• Infants can only survive if there is a shunt between the two sides of the heart, and an atrial septal defect needs to be actually enlarged to allow adequate mixing of blood to deliver enough oxygenated blood to the body.
• Significant advances have been made in the surgical treatment of this disorder.
Normal

Question 42

Truncus Arteriosus.

Answer 42

• As in the case of transposition, in this situation the origin of the “great vessels” (the aorta and pulmonary arteries) is abnormal.
• In this case, both arise from a common “trunk”.
• Blood from both ventricles mixes together as it all exits through the single valve exiting from the heart.
• The treatment of Truncus involves sewing a flexible tube with its own valve from the right ventricle to bring blood to the pulmonary arteries.

Question 43

Ebstein’s Anomaly.

Answer 43

the tricuspid valve, the valve which lies between the right atrium and right ventricle.
• While there is free flow of blood forward across the tricuspid valve to the right ventricle, the deformed tricuspid valve allows a large amount of blood to flow backwards from the right ventricle to right atrium when the right ventricle contracts.
• The treatment of this disorder depends on whether or not the person with it has any symptoms.
• At the milder end of the spectrum it will be acyanotic. If the tricuspid valve is severely incompetent then the right atrial pressure will be significantly increased. If there is an associated ASD then you will get a right to left shunt at atrial level giving some degree of cyanosis. Depending on severity and the size of the ASD this may be present at birth or may develop later in life. It can also happen in the presence of a patent foramen ovale.
• Surgery is sometimes required early in life. On the other hand, people may have a normal life expectancy.
Normal

Question 44

Total Anomalous Pulmonary Venous Drainage.

Answer 44

• The Pulmonary Veins, which carry blood back to the heart after it has circulated through the lungs, are not connected to the left atrium.
• Instead they are connected to one of the veins from the main circulation so that the blood returning from the lungs drains back to the right side of the heart.
• The affected babies may be blue or show signs of heart failure.
• Most of them require surgical repair in the newborn period.

Question 45

Atrioventricular Septal Defect (AVSD)

Answer 45

• An AVSD is a heart defect in which there are holes between the chambers of the right and left sides of the heart, and the valves that control the flow of blood between these chambers may not be formed correctly.
• This condition is also called atrioventricular canal (AV canal) defect or endocardial cushion defect.
• AVSD is common in babies with Down syndrome, a genetic condition that involves an extra chromosome 21 (also called trisomy 21).

Question 46

Causes of sudden unexpected collapse in first week of life.

Answer 46

• Duct dependent CHD.
• Sepsis (particularly Group
B Strep).
• Hypoglycaemia.
• Congenital Adrenal Hyperplasia.
• Inborn errors of metabolism.

Question 47

Eisenmenger’s Syndrome.

Answer 47

• Shunt reversal.
• Initially large left to right shunt such
as large VSD.
• Patient develops Pulmonary Arterial Hypertension to the point of right sided heart pressure exceeding left with shunt reversal and development of cyanosis.
• “Acquired Cyanotic Heart Disease”.
• Poor prognosis.
• Treatment is generally supportive, but heart and lung transplantation may be an option when symptoms are severe.