Surgical Treatment for

Tetralogy of Fallot Masakazu Nakao

Consultant, Paediatric Cardiothoracic Surgery

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History

2015

Blalock-Taussig shunt

(Blalock & Taussig)

1944 1946 1948 1954 1955 1962

Potts shunt (Potts)

Brock procedure

(Brock)

Intracardiac repair of TOF with

cross-circulation (Lillehei)

Intracardiac repair of

TOF with CPB (Kirklin))

Waterston shunt

(Waterston)

Today

1980

Modified BT shunt

(de Leval)

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Indications

“Blue” Fallot: SaO2 < 75%

Hypoxaemic spell

Otherwise, operate electively around 12 months

“Pink” Fallot: Same as VSD

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Surgical Treatment - Overview

• Palliative –

• Corrective – VSD closure +

Systemic-to-pulmonary shunt

Right ventricular outflow tract patch

Right ventricle-to-pulmonary shunt

Right ventricle-to-pulmonary stent

Infundibulectomy only

Transannular patch with/without valve

Pulmonary valve preservation

When to choose palliative, when to choose corrective?

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Surgical Treatment - Palliative vs Corrective

TOF

Symptomatic

> 3 month-old

Branch PA

Z-score >2

Corrective repair

Palliation

Palliation

Asymptomatic

Corrective repair

Yes No

Yes No

Aim of palliation

1. Increase pulmonary blood flow

2. Let branch PAs grow

3. Let the patient grow

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PA Index Pre-branching RPA diameter + LPA diameter

Descending aorta diameter at the diaphragm McGoon ratio

Pre-branching RPA area + LPA area

Body surface area Nakata index

The risks of failure of the corrective repair is higher for less than 1.0 (normal range: 2.0-2.5)

Lower Nakata index (< 150~200) has been identified as a risk factor

(normal range: 330±30mm2/BSA)

The usefulness of these indices is controversial

the compliance of the pulmonary vascular bed

distortion of the pulmonary arteries

They don’t consider

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Neonatal Repair vs Late Repair

Benefits of neonatal repair

1. Promote normal growth and development of organs

2. Eliminate hypoxaemia

3. Operate before extensive right ventricular hypertrophy

4. Better late left ventricular function

5. Decreased incidence of late dysrhythmias

6. No multiple procedures

Benefits of late repair (>3~6 months)

1. Lower mortality

2. Better chance of avoiding transannular patch

3. Shorter ICU stay

4. Lower incidence of re-intervention

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Surgical Treatment – Palliative

• Palliative –

Systemic-to-pulmonary shunt

Right ventricular outflow tract patch

Right ventricle-to-pulmonary shunt

Right ventricle-to-pulmonary stent

Which technique to be used?

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Surgical Treatment - Systemic-to-pulmonary shunt

Modified BT shunt Potts shunt Waterston shunt

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Surgical Treatment - RVOT Patch & RV-PA Shunt

1. Adopted from Bove EL, Hirsch JC. Tetralogy of Fallot : Surgery for congenital heart defect, third

edition. Eds. Stark JF, et al. John Wiley & Sons, 2006:399-410

2. Adopted from Brizard CP, et al. Pulmonary atresia, VSD and mapcas: repair without unifocalization.

Semin Thorac Cardiovasc Surg Pediatr Card Surg Ann 12:139-144

1. 2.

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Surgical Treatment - RVOT Stent

David J. Barron DJ, et al. Surgery following primary right ventricular outflow tract stenting for Fallot’s

tetralogy and variants: rehabilitation of small pulmonary arteries Eur J Cardiothorac Surg 2013;44:656-662

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BT shunt RV-PA stent/patch/shunt

Mortality 7~8% in CCAD, STS

Some reported >15% Small cohort reports only (2~3%)

Diastolic control No Yes

Landmark for coronary artery

during the second stage No

No

Yes – if patch or shunt

Stress on RV No change Reduced

Shear stress Arterial pressure Pulsatile flow

Flow limiting factor (inflow and

outflow)

Inflow – bracheocephalic

Outflow - RPA

Inflow – size of stent / patch / shunt

Outflow – MPA / LPA

CPB No / sometimes Yes No / Yes

BT Shunt vs RA-PA Stent/Patch/Shunt

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Concerns in Postoperative TOF & TOF/PA

• Right ventricular hypertrophy

• RV fibrosis

• Restrictive RV physiology

• Severe third spacing

• Haemodynamic instability

• Prolonged chest tube

Is RV-PA patch / shunt better?

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Inconsistent Choices

Birmingham Children’s Hospital

• BT shunt for PA

• RV-PA stent for TOF

• RV-PA shunt for Norwood stage I

Great Ormond Street Hospital for Children

• RV-PA shunt for PA

• RV-PA patch for TOF

• BT shunt for Norwood stage I

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Birmingham Criteria for RVOT Stent

• Low birth-weight neonates

• < 4 kg

• Branch PAs Z-score < −2

• Complex anatomy or comorbidity

- AVSD / Fallot

- anomalous LAD,

- unroofed coronary sinus,

- chronic lung disease

David J. Barron DJ, et al. Surgery following primary right ventricular outflow tract stenting for Fallot’s

tetralogy and variants: rehabilitation of small pulmonary arteries Eur J Cardiothorac Surg 2013;44:656-662

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PA growth (Z-scores) at the time of RVOT stenting and prior to surgery.

Adopted from David J. Barron DJ, et al. Surgery following primary right ventricular outflow tract stenting for

Fallot’s tetralogy and variants: rehabilitation of small pulmonary arteries Eur J Cardiothorac Surg 2013;44:656-

662

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Choice of Size

• Restrictive patch

– Small enough to restrict flow from VSD

• Should have L R shunt > R L shunt

• PA pressure < ½ systemic

• Some suggested 5, others 6mm for shunt

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Surgical Treatment – Corrective

• Corrective – VSD closure +

Infundibulectomy only

Transannular patch with/without valve

Pulmonary valve sparing surgery

Surgery consists of

1. Infundibulectomy

2. VSD closure

3. ±RVOT reconstruction

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Surgical Treatment - Infundibulectomy

1. Identify trabecular septomarginalis

2. Resect large septoprietal band

3. No more band before pulmonary valve

4. Divide smaller ones

- important to understand septum shape 1

2 2

3

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Adopted from Bove EL, Hirsch JC. Tetralogy of Fallot : Surgery for congenital heart defect, third

edition. Eds. Stark JF, et al. John Wiley & Sons, 2006:399-410

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1

1’

1’’

Surgical Treatment VSD Closure

1. Pay attention to valleys

1: between tricuspid and aortic valve

1’: behind aortic valve

1’’: between superior and inferior rim of TSM

2. Conduction

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1’’ 1’

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Adopted from Bove EL, Hirsch JC. Tetralogy of Fallot : Surgery for congenital heart defect, third

edition. Eds. Stark JF, et al. John Wiley & Sons, 2006:399-410

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Surgical Treatment

- RVOT Reconstruction

1. Determine the size you aim for

2. Estimate the patch size

3. Ensure the size is enough in every dimension

4. ± monocusp

Adopted from Bove EL, Hirsch JC. Tetralogy of Fallot : Surgery for congenital heart defect, third

edition. Eds. Stark JF, et al. John Wiley & Sons, 2006:399-410

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Monocusp 1.

2.

1. Adopted from Sasson L, et al. Right ventricular outflow

tract strategies for repair of tetralogy of Fallot: effect of

monocusp valve reconstruction. Eur J Cardiothorac

Surg 2013;43:743–751

2. Adopted from Park CS, et al. The long-term result of

total repair for tetralogy of Fallot. Eur J Cardiothorac

Surg 2010;39:311-317

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Surgical Treatment - Pulmonary Valve Sparing

1. Only PV thinning and commissurotomy

2. Add intraoperative balloon dilation

3. Incision of anterior leaflet and patch augmentation

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2

3

Bacha E, et al. Valve-sparing options in tetralogy of Fallot surgery. 2013;18(4):316-327

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Short-Term Mortality

• 1950s – 20%

• 1960 ~ 1980 – 5%

• Contemporary data – 0~3%

EACTS congenital database

Adotepd from Karl T, Stocker C. Tetralogy of Fallot and its variants. Pediatr Crit Care Med 2016;17:S330–S336

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Long -Term Mortality

Adopted from Park CS, et al. The long-term result of total repair for tetralogy of

Fallot. Eur J Cardiothorac Surg 2010;39:311-317

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Short-Term Morbidities

• Residual shunt

• Complete heart block

• Tricuspid valve regurgitation

• Aortic regurgitation

• Pulmonary regurgitation

• Restrictive right ventricular physiology

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Long-Term Morbidities

• Arrhythmias

• Right ventricular ouflow tract obstruction

• Pulmonary regurgitation

• RV dilatation PV replacement

• Reduced right ventricular function

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Adopted from Park CS, et al. The long-term result of total repair for tetralogy of

Fallot. Eur J Cardiothorac Surg 2010;39:311-317

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Other Variations

• Absent pulmonary valve syndrome

• TOF + AVSD

• Strategy for small branch PAs

• Pulmonary atresia

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Conclusion

• Surgical repair has excellent outcome

• While there is general consensus that repair should be

performed between 3 and 12 months, controversy

persists regarding neonatal repair and staged repair

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Further Reading

1. Park CS, et al. The long-term result of total repair for tetralogy of

Fallot. Eur J Cardiothorac Surg 2010;39:311-317

2. Karl T, Stocker C. Tetralogy of Fallot and its variants. Pediatr Crit

Care Med 2016;17:S330–S336

3. Apitz C, et al. Tetralogy of Fallot. Lancet 2009; 374: 1462–71

4. Sasson L, et al. Right ventricular outflow tract strategies for repair

of tetralogy of Fallot: effect of monocusp valve reconstruction. Eur J

Cardiothorac Surg 2013;43:743–751

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