Tetralogy Of Fallot

Question 1

_________________ is the most common cyanotic congenital heart disease thus it’s important to have a good understanding of the condition.

Answer 1

Tetralogy of Fallot (TOF)

Question 2

As the name implies, TOF is a tetrad of:

?????

Answer 2

Ventricular septal defect (VSD)
Pulmonary stenosis (PS)
Right ventricular hypertrophy (RVH)
Overriding aorta

Question 3

Risk factors for TOF

Males or Females??
1st degree family history of _______

Teratogens:
_______ (__________ syndrome)
________ (__________ syndrome)
________________ : antiepileptic drug used in treatment resistant epilepsy4

Answer 3

Males

CHD

Alcohol (fetal alcohol syndrome)

Warfarin (fetal warfarin syndrome)

Trimethadione

Question 4

Risk factors for TOF

Genetics:

________ syndrome (CHD7 mutation – 65%1):

________ syndrome (22q11 deletion – 50%1)

___________ association (sporadic –20%1):

Answer 4

CHARGE syndrome

Di George syndrome

VACTERL association

Question 5

CHARGE syndrome (CHD7 mutation – 65%1): ???

Answer 5

Coloboma
Heart defects
Atresia choanae
Retardation of growth/development
Genitourinary anomalies
Ear anomalies

Question 6

VACTERL association (sporadic –20%1):???

Answer 6

Vertebral anomalies
Anorectal malformation
Cardiac defects
Tracheo-esophageal fistula
Renal anomalies
Limb abnormalities

Question 7

When the VSD involves parts of the membranous and muscular septum, this is called a ______________ VSD

Answer 7

perimembranous

Question 8

_______________ this is the commonest type of VSD associated with TOF

Other VSDs associated with TOF are _________ VSDs and ______________ VSDs

Answer 8

Perimembraneous

muscular

doubly committed

Question 9

Doubly committed VSD is located ___________________________

Answer 9

near both pulmonary and aortic valves

Question 10

Pulmonary stenosis can be classified according to its location. The commonest site is the ___________________ (50%).

The stenosis may also be _______ (10%) or a combination of both (30%).

Answer 10

infundibular septum

valvular

Question 11

————— of TOF usually develops in utero and may be seen in chest x-rays as the ‘ ______’ sign.

Answer 11

Right ventricular Hypertrophy

boot

Question 12

Overriding aorta

Compared to the normal heart, the aorta in TOF is dilated and displaced over the __________________. Aortic dilatation is caused by an increase in blood flow through the aorta as it receives blood from both ventricles via the VSD.

In severe TOF, __________________________ (“MAPCAs”) may also form to help increase pulmonary blood flow.

Answer 12

intraventricular septum

multiple aorto-pulmonary collateral arteries

Question 13

Mild (‘______’ TOF)

These infants have mild PS/RVH and are usually asymptomatic. However, the disease normally progresses as the child and the heart grows thus by age ___________ they will develop cyanosis.

Answer 13

Pink; 1-3 years

Question 14

Moderate-Severe (________TOF)

Infants born with moderate-severe PS may present in the first ________ of life with ________ and ___________ . These infants may be prone to develop recurrent _________ or __________.

Answer 14

Cyanotic

few weeks ; cyanosis and respiratory distress

chest infections

fail to thrive.

Question 15

Extreme

These can be further divided into TOF with ___________ (10% of TOF patients) or ________________ (6%).

These are true ‘——————— lesions’ as the only way deoxygenated blood can flow into the lungs is through a ___________________ . These infants are often detected on antenatal scans. However, if undetected in pregnancy they will present within the first few ________ of life with marked respiratory distress and cyanosis

Answer 15

pulmonary atresia

absent pulmonary valves

duct dependent

patent ductus arteriosus (PDA)

hours

Question 16

Hypoxic (“_____”) Spells

Peak age of incidence is usually between ___________ of life. These are characterised by:

Paroxysm of ___________

_____________

Increasing _________

Answer 16

Tet; 2-4 months

hyperpnoea ; Irritability; cyanosis

Question 17

__________ should be suspected in any infant with respiratory distress and hypoxia.

Answer 17

Sepsis

Question 18

____________ is the gold standard for confirmation of diagnosis of TOF

Answer 18

Echocardiogram

Question 19

Management of TOF

Medical

Squatting: this manoeuvre helps increase ___________, therefore increases ___________.

Prostaglandin (PG) infusion: this helps ____________ in the more severe-extreme forms of TOF

Beta-blockers: It works by ———————- thus venous return .

Morphine: reduces ____________ therefore also reduces hyperpnoea

Saline 0.9% bolus can be used in “tet” spells as a volume expander to increase pulmonary blood flow through the RVOTO.

Answer 19

venous return; systemic resistance

maintain PDA ; reducing the heart rate

respiratory drive

Question 20

Surgical definitive repair of TOF

Timing depends on severity of symptoms but usually not performed younger than ___________ old or older than ________.

Answer 20

3 months

4 years

Question 21

Even post corrective surgery, patients are at higher risk of developing long term complications such as _____________ (PR), arrhythmias, exercise intolerance and sudden death.

Answer 21

pulmonary regurgitation