Congenital heart disease

Question 1

What is the most common form of congenital heart disease?

Answer 1

Ventricular septal defects

Question 2

Risk factors for congenital heart disease

Answer 2

• Down syndrome
• Maternal alcoholism and smoking
• Preterm infants
• Family history of congenital heart disease in a first degree relative increases the risk from 1% to 4%
• Maternal factors: poorly controlled diabetes, hypertension, rubella infection or systemic lupus erythematosus
• Marfan syndrome, DiGeorge syndrome
• Teratogenc drugs eg lithium, certain anticonvulsants, ACE inhibitors

Question 3

Pathophysiology of Eisenmenger syndrome

Answer 3

An atrial or ventricular septal defect causes a left to right shunt which results in increased pulmonary blood flow that can progressively lead to increased pulmonary artery pressure. This leads to pulmonary hypertension. When the pulmonary pressure exceeds the systemic pressure, this causes a right to left shunt. This causes deoxygenated blood to bypass the lungs resulting in cyanosis.

Question 4

# Define patent ductus arteriosis
Epidemiology

Answer 4

A patent ductus arteriosis refers to a congenital heart defect caused by a failure of closure of the ductus arteriosis soon after birth. This condition accounts for 10% of all congenital heart disease and is more common in premature infants.

Question 5

Clinical features of patent ductus arteriosis

Answer 5

• Usually asymptomatic if small, and is characterised by a continuous machinery like murmur on examination
• A larger shunt may produce a bounding pulse and symptoms of heart failure (poor feeding and faltering growth in children)

Question 6

Investigations and management of patent ductus arteriosus

Answer 6

Echocardiography is the investigation of choice.

Premature neonates (<37 weeks) may have their PDA closed using an NSAID such as indomethacin or ibuprofen.

Term neonates should receive transcatheter closure of the PDA, or surgical repair if the defect is too large.

Question 7

Definition of coarctation of the aorta

Answer 7

A narrowing of the aorta. It is almost always congenital.

Question 8

Key associations with coarctation of the aorta

Answer 8

• Bicuspid aortic valve
• Cerebral berry aneurysms
• Turner syndrome

Question 9

Clinical features of coarctation of the aorta

Answer 9

• Patients may present with symptoms of heart failure
• May have radio-femoral or radio-radial pulse delays or an absent femoral pulse in children
• Differences in BP and oxygen saturation may also be seen

Question 10

Complications of coarctation of the aorta if not repaired

Answer 10

• Aortic dissection
• Left ventricular failure

Question 11

Investigations and management of coarctation of the aorta

Answer 11

Echocardiography is the first line investigation.

Management is balloon angioplasty, stenting or surgical repair depending on the presentation of the disease in the context of symptoms and the size of the defect.

Question 12

Definition of an atrial septal defect

Answer 12

An atrial septal defect refers to a communication between the left and the right atria.

Question 13

Epidemiology of atrial septal defect

Answer 13

• Accounts for up to 10% of all congenital heart defects
• Ostium secundum defects are the most prevalent

Question 14

Clinical features of an atrial septal defect

Answer 14

• ASDs are usually asymptomatic
• A systolic murmur may be heard on the upper left sternal edge, with characteristic fixed splitting of the second heart sound as a result of pulmonary valve delay closure
• Atrial fibrillation may occur later on in life, as might heart failure secondary to progressive right heart dilation

Question 15

Investigation and management of atrial septal defect

Answer 15

Echocardiography

Transcatheter closure may be used for most defects, but very large ASDs and primum ASDs require surgical closure

Question 16

Define ventricular septal defect

Answer 16

A ventricular septal defect refers to a communication between the left and right ventricles.

Question 17

Epidemiology of ventricular septal defect

Answer 17

• Most common congenital heart defect, accounting for 30% of all congenital heart defects at birth
• Only accounts for 10% of CHD in adults, because many close spontaneously

Question 18

Clinical features of ventricular septal defect

Answer 18

• A small VSD is asymptomatic
• Symptoms such as dyspnoea, faltering growth and poor feeding in children may occur in larger VSDs due to the effect of a large shunt
• A pansystolic murmur is best heard at the left lower sternal edge
• A small VSD will produce a louder murmur than a large VSD

Question 19

Investigation and management of ventricular septal defect

Answer 19

Echocardiography

Management depends on the extent of the defect and involves a choice between percutaneous closure or surgical repair

Question 20

Define Tetralogy of Fallot

Answer 20

Tetralogy of Fallot is a combination of the following four defects (PROVe)

• Pulmonary stenosis
• Right ventricular hypertrophy
• Overriding aorta
• Ventricular septal defect

Question 21

In Tetralogy of Fallot, hypercyanotic spells sometimes occur because RV outflow obstruction is exacerbated by adrenergic stimulation. There are two hypercyanotic phenomena:

Answer 21

• Tet spells, where an infant presents increasingly cyanosis, typically after crying. This is life threatening and requires immediate intervention.
• Older children may display the Fallot sign, describing a child squatting down during a hypercyanotic spell, increasing systemic vascular resistance and easing the effect of the shunt.

Question 22

Which pathology of Tetralogy of Fallot has the biggest effect on the severity of the disease?

Answer 22

The degree of pulmonary stenosis

Question 23

Signs and symptoms of Tetralogy of Fallot

Answer 23

• Cyanosis (blue discolouration of the skin due to low oxygen saturation)
• Clubbing
• Poor feeding
• Poor weight gain
• Ejection systolic murmur heard loudest in the pulmonary area
• Tet spells

Question 24

Tetralogy of Fallot investigations and management

Answer 24

Echocardiography

Complete surgical repair is indicated, preferably before the child turns five years old

Question 25

Define transposition of the great arteries.

How does it present?

Answer 25

Transposition of the great arteries refers to the phenomenon in which the great arteries are transposed and originate from the opposite ventricular outflow tract.

It presents with early, profound cyanosis.

Question 26

Investigations and management for transposition of the great arteries

Answer 26

Echocardiography demonstrates the defect and prompt surgical repair should be carried out, ideally within the first few weeks of life.