Tetralogy of Fallot

Consists of a triad of
  1. Ventricular Septal Defect as large as aortic value annulus
  2. Overriding of aorta
  3. Right ventricular outflow tract obstruction / Pulmonary Stenosis
  4. Right ventricular hypertrophy

Clinical Presentation
  • Symptoms develop anytime after birth
  • Clubbing and Cyanosis
  • Mild ( RVOT ) obstruction – Presents with an isolated murmur ( Pink tetralogy )
  • Severe obstruction –
    • Presents with cyanosis, a prominent parasternal heave
    • S2 – late and soft P2 ( inaudible), A2 is the single and audible sound
Cyanotic spells
  • Dyspnea on exertion ( like excessive crying ) or in morning
  • The toddlers assume a squatting position after physical exertion
  • Child starts crying → Becomes more hyperpnoeic → Cyanosis deepens ( child becomes bluer ) → Syncope → Severe spells may lead to convulsions

Physical Examination
  • Cyanosis and Clubbing present
  • Slight prominent a waves in JVP
  • Normal S1, Single S2 heard
  • Ejection systolic murmur


  • RVH and Right axis deviation
  • T waves are usually inverted
  • P pulmonale may be present

Chest X ray – Boot shaped heart

For confirmation – ECHO, Cardiac catheterization in specific cases


  • Pulmonary stenosis becomes severe with age
  • Dyspnea and increasing exercise intolerance.
  • Anemia
  • Cardiac enlargement & congestive cardiac failure
  • Patients prone to infective endocarditis
  • Anoxic infarction in the central nervous system occurs leading to hemiplegia
  • Hemiplegia can also occur due to paradoxical embolism to CNS and venous thrombosis
  • Brain abscess
  • Congested retina and papilledema

For cyanotic spells –

  • Oral Propranolol ( 0.5 – 1.5 mg / kg / dose)
  • Iron supplementation


  • Closure of VSD and relief of pulmonary stenosis
  • Relief involves placement of transannular patch across the pulmonary value


  • Blalock- Taussig Shunt – Subclavian artery- pulmonary artery anastomosis using a Goretex graft
  • Alternatives – Balloon dilatation of the pulmonary value or stenting of patent arterial duct

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Mujtaba hashim

Thanks for alot information