Paeds · cardiology
Tetralogy of Fallot
Also known as TOF · Fallot's tetralogy · Cyanotic congenital heart disease - tetralogy of Fallot
Fellowship guide to tetralogy of Fallot in children: the four features that share one embryologic fault, the severity spectrum from pink TOF to pulmonary atresia, the hypercyanotic tet spell and how to break it, the echo-to-MRI diagnostic strategy, primary repair versus staged palliation, the late burden of pulmonary regurgitation and sudden cardiac death, and the ANZ, AHA/ACC and ESC guideline positions.
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Red flags
- A hypercyanotic 'tet' spell is a treated emergency, not an observed curiosity — knee–chest position, oxygen, morphine, fluid and an alpha-agonist such as phenylephrine, escalating to an urgent surgical or catheter shunt if it does not break
- In a tet spell the murmur becomes softer and cyanosis deepens — the worsening child is the one whose obstructive murmur is disappearing
- Tetralogy of Fallot with pulmonary atresia is duct-dependent — start a prostaglandin infusion immediately on suspicion and do not wait for the echo to confirm anatomy
- A repaired patient with a QRS duration over 180 ms is at high risk of sustained ventricular tachycardia and sudden cardiac death — refer for electrophysiological risk stratification
- Screen every child with tetralogy of Fallot for 22q11.2 deletion — it changes perioperative care, calcium and immune management, and long-term neurodevelopmental surveillance
Life stages
Care settings
Clinical exam formats
Board mappings
- Cardiology
- Congenital heart disease
- Tetralogy of Fallot
- Paediatric Cardiology — cyanotic congenital heart disease
- General Paediatrics learning goal — recognise and stabilise cyanotic CHD
- Lifelong surveillance after surgical repair
- Clinical Applications
- Long Cases
- Short Cases
- Communication scenarios
- Cardiology: recognises and manages cyanotic congenital heart disease
- Neonatal presentation of duct-dependent circulation
- Lifelong follow-up after surgical repair
- Foundation of Practice (FOP)
- Applied Knowledge in Practice (AKP)
- Clinical
- History
- Communication
- Cardiovascular examination
- General Pediatrics Content Outline — Domain 9: Cardiology
- Subspecialty: Pediatric Cardiology — congenital heart disease
- Cyanotic congenital heart disease
- Patient Care 1: History and Physical Examination
- Patient Care 4: Clinical Reasoning
- Medical Knowledge 1: Clinical Knowledge of congenital heart disease
- Systems-Based Practice 1: multidisciplinary cardiac surgical care
- Medical Expert
- Collaborator
- Pediatrics: Core EPA — recognise and stabilise cyanotic CHD
Overview & Definition
Picture the four-month-old brought in crying and blue after a feed, knees drawn up to the chest, who looks a little better when you hold her that way. Her mother has noticed her going duskier with feeds for weeks, and today she is saturating 72 per cent in air with a loud systolic murmur at the left upper sternal border. That child carries the whole story of tetralogy of Fallot — a cyanotic congenital heart defect whose severity swings with the degree of outflow obstruction, and whose most dangerous moment before surgery is the paroxysm you are now watching. [1]
Tetralogy of Fallot is the commonest cyanotic congenital heart lesion presenting beyond the neonatal period, with an incidence of roughly three to four per ten thousand live births. The four classical features — ventricular septal defect, right ventricular outflow tract obstruction, overriding aorta and right ventricular hypertrophy — are not four separate problems but the downstream consequences of a single malformation, anterocephalad deviation of the infundibular septum. This is the single most important concept for the viva: name the unifying embryologic fault and the four features follow. [7] [8]
The clinical importance of TOF rests on three facts. It is surgically curable, with operative mortality now under one to two per cent in modern centres, so the goal is recognition and safe transfer to surgery. It is the archetype of a duct-independent cyanotic lesion that nonetheless declares itself over weeks as obstruction worsens. And it is never truly "done" after repair, because the late burden of pulmonary regurgitation, arrhythmia and sudden cardiac death means every repaired patient needs lifelong follow-up. [1] [2]
References15ShowHide
- [1]Apitz C, Webb GD, Redington AN Tetralogy of Fallot. Lancet, 2009.PMID 19683809
- [2]Villafañe J, Feinstein JA, Jenkins KJ, Vincent RN, Walsh EP, et al. Hot topics in tetralogy of Fallot. J Am Coll Cardiol, 2013.PMID 24076489
- [3]Khairy P, Aboulhosn J, Gurvitz MZ, Opotowsky AR, Mongeon FP, et al. Arrhythmia burden in adults with surgically repaired tetralogy of Fallot: a multi-institutional study. Circulation, 2010.PMID 20713900
- [4]Valente AM, Gauvreau K, Assenza GE, Babu-Narayan SV, Schreier J, et al. Contemporary predictors of death and sustained ventricular tachycardia in patients with repaired tetralogy of Fallot enrolled in the INDICATOR cohort. Heart, 2014.PMID 24179163
- [5]Mercer-Rosa L, Pinto N, Yang W, Tanel R, Goldmuntz E 22q11.2 Deletion syndrome is associated with perioperative outcome in tetralogy of Fallot. J Thorac Cardiovasc Surg, 2013.PMID 23312975
- [6]Joshi A, Ghadimi Mahani M, Dorfman A, Balasubramanian S Cardiac MR Evaluation of Repaired Tetralogy of Fallot. Semin Roentgenol, 2020.PMID 32859345
- [7]Anderson RH, Sarwark A, Spicer DE, Backer CL Exercises in anatomy: tetralogy of Fallot. Multimedia Manual Cardiothorac Surg, 2014.PMID 25500768
- [8]Anderson RH, Weinberg PM The clinical anatomy of tetralogy of fallot. Cardiol Young, 2005.PMID 15934690
- [9]Geva T Indications and timing of pulmonary valve replacement after tetralogy of Fallot repair. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu, 2006.PMID 16638542
- [10]McDonald-McGinn DM, Sullivan KE, Marino B, Philip N, Swillen A, et al. 22q11.2 deletion syndrome. Nat Rev Dis Primers, 2015.PMID 27189754
- [11]Maury P, Sacher F, Rollin A, Mondoly P, Duparc A, et al. Ventricular arrhythmias and sudden death in tetralogy of Fallot. Arch Cardiovasc Dis, 2017.PMID 28222965
- [12]Grzyb A, Koleśnik A, Bokiniec R, Szymkiewicz-Dangel J Tetralogy of Fallot in the fetus - from diagnosis to delivery. 18-year experience of a tertiary Fetal Cardiology Center. Kardiol Pol, 2022.PMID 35579022
- [13]Montero JV, Nieto EM, Vallejo IR, Montero SV Intranasal midazolam for the emergency management of hypercyanotic spells in tetralogy of Fallot. Pediatr Emerg Care, 2015.PMID 25831027
- [14]Sandoval JP, Chaturvedi RR, Benson L, Morgan G, Van Arsdell G, et al. Right Ventricular Outflow Tract Stenting in Tetralogy of Fallot Infants With Risk Factors for Early Primary Repair. Circ Cardiovasc Interv, 2016.PMID 27965298
- [15]Bacha EA, Scheule AM, Zurakowski D, Erickson LC, Hung J, et al. Long-term results after early primary repair of tetralogy of Fallot. J Thorac Cardiovasc Surg, 2001.PMID 11436049