1. TETRALOGY OF FALLOT AND RIGHT VENTRICULAR OUTFLOW TRACT OBSTRUCTION
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2. "Dr.Blalock,I stand in awe and admiration of your surgical skill but the truly great day will be when you build a ductus for the child dying of anoxemia and not when you tie off a ductus for a child with a little too much blood going this lungs. "Dr. Blalock gave a Sigh and replied, "When that day comes, this will seem like child's play."

3. Outline Anatomical Features Associated Anomalies and Fallot Variants
Physiology and Clinical Presentation
Natural History
Diagnosis
Surgical Treatment
Modified Blalock-Taussig shunt
Technique of complete repair
Post-operative Care and Results
Anatomical Subsets
Absent pulmonary valve syndrome
With atrioventricular septal defect
With anomalous course of coronary artery

4. Anatomical features DEFINITION
Due to antero-cephalad deviation of outlet septum leading to:
Unrestricted malaligned large subaortic VSD;
RVOTO at any level;
Consequent RVH and
An overriding aorta(<50%)
Additional features include muscular VSD, anomalous coronaries, PDA, MAPCAs(esp with pulm.atresia) and RSAarch
Pentalogy of Fallot has an ASD or PFO

5. D. Mayer and C. Mullins, Congenital Heart Disease, A Diagrammatic Atlas. New York: Alan R. Liss, Inc, p. 5.

6. ASSOCIATED ANOMALIES PERSISTENT PATENCY OF THE FORAMEN OVALE AND ASD
ADDITIONAL MUSCULAR VSD
11% HAVE PERSISTENT LEFT SVC
ABERRANT ORIGIN OF THE LEFT CORONARY 5 TO 15%. LAD ARISES FROM RCA
20 TO 25% HAVE A RIGHT SIDED AORTIC ARCH
<5% HAVE MAPCAs

7. ANATOMIC VARIANTS TET PULMONARY ATRESIA WITH OR WITHOUT MAPCAs
TET WITH ABSENT PULMONARY VALVE
TET WITH DOUBLE OUTLET RIGHT VENTRICLE
TET WITH ATRIOVENTRICULAR SEPTAL DEFECT

8. PHYSIOLOGY AND CLINICAL PRESENTATION
PRESENTATION VARIES DEPENDING ON THE SEVERITY OF RVOTO
MILD OR NO CYANOSIS WILL PRESENT LATER WHEN RVOTO WORSENS
CLUBBING IS SEEN IN LONG STANDING CYANOSIS
TET-SPELLS ARE EPISODES OF CYANOTIC HYPOXAEMIC ATTACKS. TREATMENT CONSISTS OF INCREASING LV AFTERLOAD.
Fyler DC (1992) Tetralogy of Fallot. In: Keane JF, Dyler DC, Lock JE, Nadas’ (eds) Pediatric cardiology. Hanley & Belfus, Philadelphia, pp

9. NATURAL HISTORY VARIABLE AND DEPENDS ON THE SEVERITY OF RVOTO
25% WITH SEVERE RVOTO DIE IN THE FIRST YEAR IF NOT SURGICALLY TREATED
IF NOT TREATED 40% DIE BY AGE 3 YEARS, 70% BY AGE 10 YEARS AND 95% BY AGE OF 40 YEARS.
MAJOR CAUSES OF DEATH IF UNTREATED INCLUDES HYPOXAEMIC SPELLS AT 62%, CVI AT 17% AND BRAIN ABSCESSES AT 13%
HIGHEST RISK OF DEATH IS IN THE FIRST YEAR AND THEN IT REMAINS CONSTANT UNTIL AGE 25 YEARS AND THEN INCREASES.
Loh TF, Ang YH, Wong YK et al (1973) Fallot’s tetralogy-natural history. Singap Med J 14:

10. DIAGNOSIS
PHYSICAL EXAM
CXR AND ECG

11. http://www. google. co. za/url

12. DIAGNOSIS LAB STUDIES ECHOCARDIOGRAPHY CATHETERIZATION
POLYCYTHEMIA WITH CYANOSIS
STUDIES FOR DELETION ON LONG ARM OF CHROMOSOME 22. ACRONYM CATCH-22
ECHOCARDIOGRAPHY
DEFINITIVE DIAGNOSTIC MODALITY
NUMBER AND LOCATION OF VSD’s
ANATOMY AND PULMONARY ARTERIES
CORONARY ARTERY PATTERN
PRENATAL DIAGNOSIS ACCURATE
CATHETERIZATION
HIGHLY ACCURATE AND INVASIVE
WHEN SUSPECTING MAPCAs
INTERVENTION

13. SURGICAL TREATMENT

14. Surgical repair Historical perspective
augmenting blood flow to the lungs, Blalock and Taussig shunt.
Lillehei et al, using controlled cross-circulation, performed first Tet correction in 1954
When to repair depends in part on the degee of cyanosis.

15. Surgical repair Palliation
Blalock-Taussig shunt or modification (subclavian artery-to-pulmonary artery shunt).
Waterston shunt (ascending aorta-to-right pulmonary artery).
Potts shunt (descending aorta-to-left pulmonary artery).
Central interposition tube graft.
Infundibular resection (Brock procedure) or pulmonary valvotomy.
RV-to-PA conduit without VSD closure or with fenestrated closure

16. Surgical repair Technique ( first series late 1960’s)
VSD repair via right ventriculotomy
Resection of the RVOT muscle bundles and pulmonary valve
Long term results
Aortic and pulmonary valve insufficiency
RV dilatation
Reinterventions

17. Surgical repair Recent era from 1970 to present
Complete repair in younger age including neonates
Barratt-Boyes BG, Neutze JM (1973) Primary repair of tetralogy of Fallot in infancy using profound hypothermia with circulatory arrest and limited cardiopulmonary bypass: a comparison with conventional two stage management. Ann Surg 178:406–411

18. Surgical repair Neonatal surgery:
McMillan noted that primary VSD closure had high incidence of heart block and death.
Bonchek and Starr concluded that early repair was advantageous with less mortality and prevention of worsening fibrosis with RVOT
Bonchek LI, Starr A, Sunderland CO et al (1973) Natural history of tetralogy of Fallot in infancy. Circulation 48:392–397

19. Shunt first then complete repair?
Surgical repair
Neonatal surgery:
Shunt first then complete repair?
Two-stage repair has high mortality( 20% early and 6% late with shunts).
Primary repair 8%
Barratt-Boyes BG, Neutze JM (1973) Primary repair of tetralogy of Fallot in infancy using profound hypothermia with circulatory arrest and limited cardiopulmonary bypass: a comparison with conventional two stage management. Ann Surg 178:406–411

20. Surgical repair Transannular patch technique:
Small PV annulus patients have improved relief of RVOT
Results in regurgitation of PV with RV volume load
Long term RV myocardial dysfunction and ventricular arrhythmias
Blackstone EH, Kirklin JW, Pacifico AD. Decision-making in the repair of tetralogy of Fallot based on intraoperative measurements of the pulmonary arterial outflow tract. J Thorac Cardiovasc Surg.1979;77:

21. Surgical repair Transatrial–transpulmonary repair:
To deal with complications related to the use of the TA Patch technique
Pulmonary valve sparing technique
Avoid resection of the RV muscle
Right ventricular to Pulmonary artery conduit
Tiny pulmonary arteries
Aberrant origin of coronay arteries
Type of conduit used is surgeon dependent

22. Future Tissue engineered valves and valved conduits
Percutaneous valves
Genetic manipulation as a therapeutic tool

23. Conclusion
Initially an incurable condition, then a condition for palliation, now it is a curable condition!

25. References
Morales DL, Zafar F, Fraser CD Jr. Tetralogy of Fallot repair: the right ventricle infundibulum sparing (RVIS) strategy. Semin Thorac Cardiovasc Surg PediatrCard Surg Annu. 2009:54-58.
Cebotari S, Lichtenberg A, Tudorache I et al (2006) Clinical application of tissue engineered human heart valves using autologous progenitor cells. Circulation 114(Suppl 1):132–137