Cardiology - Tetralogy Of Fallot

Question 1

Definition

Answer 1

CYANOTIC congenital heart disease:
Overriding aorta
Large VSD
Pulmonary stenosis
Right ventricular hypertrophy

Question 2

Epidemiology

Answer 2

More common in males
Rubella
Increased age of the mother (>40)
Diabetic mother
Alcohol consumption in pregnancy

Question 3

Pathophysiology

Answer 3

• Decreased right ventricular outflow
• Dilated and displaced aorta
• Mild: asymptomatic but as heart grows, develops cyanosis aged 1-3 year
• Moderate: Cyanosis and respiratory distress in the first few months of life
• Extreme: Often detected on antenatal scan, present with cyanosis in first few hours of life

Question 4

Signs and symptoms

Answer 4

• Ejection systolic murmur in pulmonary region (caused by pulmonary stenosis)
• Irritability
• Cyanosis
• Clubbing
• Poor feeding
• Poor weight gain
• Tet spells = cyanotic episode during physical exertion

Question 5

Investigations

Answer 5

CXR: boot shaped heart due to right ventricular thickening
MRI/Cardiac catheter
Echo With Doppler flow studies

Question 6

Treatment

Answer 6

• Prostaglandin infusion PGE1 to maintain ductus arteriosus
• Beta blockers
• Morphine to reduce respiratory drive
• Surgical: repair under bypass 3 months - 4 years but needs ICU post op

Question 7

Tet spells treatment

Answer 7

• Supplementary oxygen = hypoxic children
• Beta blockers = relax right ventricle and improve flow to the pulmonary vessels.
• IV fluids = increase pre-load, increasing the volume of blood flowing to the pulmonary vessels.
• Morphine = decrease respiratory drive = more effective breathing.
• Sodium bicarbonate = buffer metabolic acidosis
• Phenylephrine infusion = increase systemic vascular resistance.

Question 8

H

Answer 8

Pulmonary regurgitation
Lifelong follow up