Congenital Heart Defects

Question 1

Tetralogy of Fallot

Answer 1

Right Ventricular Hypertrophy
Ventricular Septal Defect
Right-sided Outflow Obstruction (Pulmonary Stenosis)
Over-riding Aorta

Question 2

In which direction is blood generally shunted in a Ventricular Septal Defect?

Answer 2

Left to right

non-cyanotic

Question 3

Where on the precordium are Ventricular Septal Defects usually best auscultated?

Answer 3

Lower left sternal edge

Accompanied by a parasternal thrill

Question 4

What is Eisenmengers Syndrome?

Answer 4

With established Ventricular Septal Defects, increased pulmonary blood flow leads to increased pulmonary vascular resistance. This causes pulmonary hypertension and the VSD shunt becomes right to left and cyanotic

Question 5

What is the treatment of choice for Ventricular Septal Defects before surgery is needed?

Answer 5

Furosemide with Spironolactone

Question 6

What is the definition of congenital heart disease?

Answer 6

A gross structural abnormality of the heart or intrathoracic great vessels that is actually or potentially of functional significance
Present at birth

Question 7

What is a “mild” defect?

Answer 7

Asymptomatic
May resolve spontaneously
May progress to moderate pr severe in adulthood in some specific conditions

Question 8

What is a “moderate” defect?

Answer 8

Requires specialist intervention and monitoring in cardiac centre

Question 9

What is a “severe” defect?

Answer 9

Present severely ill/die in newborn period or early infancy

Question 10

What is a “major” congenital heart disease?

Answer 10

Requires surgery within the first year of life

Question 11

How does an unwell baby with congenital heart disease present?

Answer 11

Cyanosis
Shock
Cardiac failure

Question 12

Why is the outcome probably better for major disease if antenatally detected?

Answer 12

Avoid cardiovascular collapse/death if undiagnosed
Minimise hypoxia
Improve condition at time of going to surgery

Question 13

How is a right to left shunt at ductus detected at newborn screening?

Answer 13

Measurement of pre and post ductal saturations
Pre = Right hand
Post = Left hand, feet
Difference of 3% or more suggests shunt

Question 14

What kinds of heart defects causes cyanosis in a newborn baby?

Answer 14

Any condition causing deoxygenated blood to bypass the lungs and enter the systemic circulation
Any condition where mixed oxygenated and deoxygenated blood enters the systemic circulation from the heart

Question 15

What is the differential diagnosis of cyanosis in a newborn, and what are the defining features of each?

Answer 15

Cardiac disease =
Babies tend to be blue
Little or no respiratory distress
Pre-post ductal difference

Respiratory disease =
Increased work of breathing
X-Ray changes

Persistent pulmonary hypertension of the newborn =
baby otherwise very unwell
Large pre-post ductal difference

Question 16

What specific congenital heart defects can cause cyanosis?

Answer 16

Transposition of great arteries
Tetralogy of Fallot
Tricuspid atresia
Pulmonary atresia with intact ventricular septum
Total anomalous pulmonary venous connections

Question 17

What has occurred in Transposition of the Great Arteries?

Answer 17

Aorta leaves from the right ventricle, and so deoxygenated blood is passed around the body without ever reaching the lungs
Pulmonary artery leaves the left ventricle, and so oxygenated blood is pumped round the lungs without ever reading the body
A patent foramen oval will allow for some mixing of blood, but this is not sufficient and treatment should be given ASAP

Question 18

What are duct dependent lesions?

Answer 18

Any conditions in which the pulmonary or systemic circulation is dependent on the potency of the ductus arteriosus
If not detected beforehand, will present with circulatory collapse when the duct closes

Question 19

What treatment can be given to maintain duct patency in duct dependent lesions?

Answer 19

ABC
Low dose prostaglandin E2
Watch for apnoea, but avoid ventilation and intubation if possible
Transfer to cardiac surgical centre for definitive management

Question 20

What is the typical presentation of undiagnosed duct dependent lesions?

Answer 20

3-5 day old infant suddenly pale, tachypnoeic and distressed
Pallor, prolonger CRT, poor or absent pulses, hepatomegaly, crepitations, increased work of breathing
Profoundly acidotic

Question 21

What is the differential diagnosis for an undiagnosed duct dependent lesion?

Answer 21

Sepsis

Metabolic conditions

Question 22

What are some duct dependent systemic circulatory conditions?

Answer 22

Hydroplastic left heart
Critical aortic stenosis
Interrupted aortic arch
Critical coarctation of aorta

Question 23

What are some cut dependent pulmonary circulatory conditions?

Answer 23

Tricuspid atresia

Pulmonary atresia

Question 24

Why might a baby present with cardiac failure?

Answer 24

Large VSD
Moderate to large left to right shunt
Increased pulmonary flow, Increased ventricular load

Question 25

What are the clinical signs of failure in babies?

Answer 25

Failure to thrive
Slow/reduced breathing 
Breathlessness (especially when feeding) 
Sweatiness
Hepatomegaly 
Crepitations