tetrology of fallot. TOF, postoperative complication and management ppt

1. Tetralogy of Fallot postoperative
complications & management
Dr Virbhan Balai
SR (Cardiology), NHI Delhi

2. Tetralogy of Fallot
Introduction
TOF is the MC form of cyanotic CHD after 1 year of age.
Incidence approaching 10% of all forms of CHD.
The defect is due to antero-cephalad deviation of the
outlet septum resulting in the following four features:
1. Non restrictive VSD - Usually subaortic
2. Overriding aorta (but < 50%)
3. RVOTO which may be infundibular, valvular, or (usually)
combination of both
4. RVH

4. Associated lesions include
Secundum ASD
Additional muscular VSD
Right aortic arch -25%
Anomalous (can be dual) LAD (3%) which may necessitate
a conduit type of repair
Complete AVSD (rare, usually in association with Down
syndrome). Pulm art hypoplasia or absent usually left
Deletion of chromosome 22q11 (previously called Di
George syndrome)- Approx. 15% of pt`s with ToF
Frequent early onset of depression or psychiatric disease

5. Clinical Course (Unrepaired)
Presentation as an Un-operated Patient
Rare US, can be seen in immigrants
Mild pulmonary obstruction and mild cyanosis
(pink tetralogy) - diagnosis may not be made until
adult life.
It is usually mistaken for a small VSD because of
the loud precordial murmur.
Severe RVOTO but abundant aorticopulmonary
collaterals may present late with cyanosis & loud
cont murmur.

7. Postsurgical Presentation
They are usually asymptomatic.
Exercise limitation
Atrial and/or ventricular arrhythmias imply
hemodynamic difficulties.

8. Clinical Features and Evaluation
Clinical Examination
The typical post repair patient has a soft ESM
from the RVOT.
Low-pitched, delayed diastolic murmur in the
pulmonary area is consistent with PR.
Usually have an absent P2
The pt may have a PSM of a VSD patch leak.
High pitched, diastolic murmur of AR

9. The occasional adult pt may present having
palliative shunt only.
Such pts usually have cyanosis and clubbing.
If the shunt is patent, a continuous murmur
may be heard.
In the presence of a prior classic Blalock-
Taussig shunt, the brachial and radial pulses
may be diminished or absent on that side.

10. Electrocardiogram
In pt`s with trans ventricular repairs (the norm
until the 1990s), complete RBBB is almost
always present, in which case QRS duration
may reflect the degree of RV dilation.
A QRS duration of ≥180 ms has been
identified as a risk factor for sustained VT &
SCD.
The presence of AFL or AF or of sustained VT
reflects severe hemodynamic difficulties.

11. Chest X-Ray
The heart size is usually normal.
Cardiomegaly usually reflects important PR
and/or TR.
The aortic arch is right sided in 25% of cases.

12. Initial Surgical Repair
Complete repair is considered-
1. In palliated patients without irreversible PAH
or unfavorable pulmonary artery anatomy.
2. As a primary operation, usually performed in
the first year of life.

13. Complete repair consists of-
1. VSD closure
2. Relief of RVOT obstruction.

14. • Primary repair between 6 and 18 months
• Perioperative mortality < 1%.
• Late survival after tetralogy repair is excellent,
with a 35-year survival of 85%.

16. Palliative procedures to increase pulmonary
blood flow
Blalock–Taussig shunt: classic or modified—
subclavian artery to PA end-to-side or with
interposition graft, respectively;
Waterston shunt: ascending aorta to right PA
shunt;
Potts shunt: descending aorta to left PA shunt

17. CLASSIC BT shunt

18. POTTS SHUNT WATERSTON SHUNT

19.  Occasionally, an extracardiac conduit must be placed from
the right ventricle to the pulmonary artery when an
anomalous coronary artery crosses the RVOT.
 If the pulmonary valve itself is abnormal, a pulmonary
valvotomy or pulmonary valve resection may be necessary.
 Effort should be made to preserve the pulmonary valve
during the primary operation when performed in infancy.
 A PFO or small ASD is usually closed.
 When complete repair is performed in adulthood,
pulmonary valve replacement may be required if the native
pulmonary valve integrity is disrupted .

20. Surgical Procedures for Repair of
TOF in Adults
 Pulmonary valve replacement
 Heterograft (porcine or pericardial) or homograft
 Mechanical PVR in patients who require warfarin anticoagulation for
other reasons. This procedure has been associated with late
malfunction from pannus formation.
 Patch augmentation of the pulmonary annulus for proper prosthetic
valve sizing
 Subvalvular obstruction or pulmonary artery stenosis
 Resection of subvalvular obstruction and/or patch augmentation of
the RVOT, pulmonary annulus, main or branch pulmonary arteries
 Usually occurs in combination with PVR
 Residual/recurrent VSD closure
 Direct suture
 Patch revision

21. AVR (tissue or mechanical) for aortic
regurgitation
Replacement of ascending aorta for dilatation
 Tube graft
 Bentall procedure (composite valved conduit with
coronary reimplantation)
Aneurysm or pseudoaneurysm formation of
RVOT
 Resection and patch replacement
Atrial arrhythmias
 Maze procedure or 1 of its modifications

22.  Ventricular arrhythmias (ventricular tachycardia, ventricular
fibrillation)
 Preoperative EP testing and ablation in the catheterization laboratory
 If unsuccessful, intraoperative mapping and ablation are performed
 Focus is most often in the RVOT between the VSD patch and the
pulmonary annulus
 Postoperative placement of an ICD for patients at high risk of sudden
death
 Tricuspid valve repair for significant tricuspid regurgitation
 Tricuspid valve replacement for a markedly abnormal tricuspid
valve
 Closure of residual PFO or ASD, especially if there is cyanosis,
history of paradoxical embolism, or anticipated need for a
permanent pacemaker or ICD.

23. Key postoperative issues
Residual pulmonary regurgitation
RV dilation and dysfunction from pulmonary
regurgitation, possibly with associated TR
Residual RVOT obstruction
Branch pulmonary artery stenosis or hypoplasia
Sustained VT
Sudden cardiac death
AV block, atrial flutter, and/or atrial fibrillation
Progressive AR
Syndromal associations.

25. Common complications in adulthood
PR: Significant PR is almost always encountered
following a transannular patch repair.
PR is usually well tolerated for years.
Severe chronic PR, however, eventually leads to
symptomatic RV dilation and dysfunction.
The severity of PR and its deleterious long-term
effects are augmented by co-existing distal PA
stenoses or PAH (the latter is uncommon).

26. † Residual RVOTO: This can occur at the
infundibulum, at the level of the pulmonary
valve and main pulmonary trunk, distally,
beyond the bifurcation, and occasionally into
the branches of the left and right PAs (the
latter frequently because of sequelae from
previous palliative surgery).

27.  RV dilation and dysfunction: RV dilation is usually due to
residual longstanding free PR+RVOTO.
 Significant TR may occur as a consequence of RV dilation,
which begets more RV dilation.
 † Residual VSD: This can be due to partial patch
dehiscence or failure of complete closure at the time of
surgery; it may lead to LV volume overload.
 † Aortic root dilation with AR: Aortic root dilation
(progressive) is seen in 15% of adults late after repair and
relates to both intrinsic abnormalities of the aorta (cystic
medial necrosis) and increased flow (i.e. patients with
pulmonary atresia).
 It commonly leads to AR and rarely to aortic dissection.

28.  LV dysfunction: Due to longstanding cyanosis before repair and/or
inadequate myocardial protection during repair (old era), LV volume
overload from longstanding palliative arterial shunts, residual VSDs,
and/or AR.
 It can also be the result of an adverse ventricular–ventricular
interaction (PR).
 † Atrial/ventricular tachycardia and SCD: This is related to
progressive haemodynamic problems and/or surgical scarring, and
thus is seen with increasing frequency with longer follow-up.
 SCD is reported in 1–6% of cases [in most instances due to
VT/ventricular fibrillation (VF)], accounting for approximately a third
to a half of late deaths.
 † Endocarditis: Endocarditis is rare.

29. Gatzoulis and colleagues reported RF for SCD
in 793 pt`s with repaired TOF from six centers
in the UK & found that older age of repair and
QRS duration 180 ms were independent
predictors of sudden death.
Multiple other organ systems may be affected,
and it is not uncommon for ACHD patients
with repaired TOF to have renal, hepatic, and
pulmonary comorbidities.

31. Incidence of Complications Post-repair

32. Problems and Pitfalls in the Patient
With Prior Repair
 The following problems occur in patients after repair of tetralogy of Fallot:
 Cardiomegaly;- on chest x-ray should prompt the search for a residual
hemodynamic lesion (commonly pulmonary regurgitation).
 The development of arrhythmias (atrial or ventricular) should prompt the
search for an underlying hemodynamic abnormality (commonly PR).
 Diagnostic confusion may occur in the context of DORV, in which the aorta
overrides the right ventricle by more than 50%. In such cases, the VSD
patch is more extensive and predisposes to the presence of postoperative
sub aortic obstruction, which should be carefully excluded.
 Hypoxemia in postoperative patients should prompt a search for a PFO or
ASD with a right-to-left shunt.
 The presence of RV enlargement or dysfunction and the presence of
important TR should prompt the search for a residual hemodynamic lesion
(commonly PR).

33. postoperative some pt`s may have LV
dysfunction.
This may related to-
Prolonged cardiopulmonary bypass,
Poor myocardial protection from an early surgical
era, or
Trauma to a coronary artery at the time of repair,
or
It may be secondary to severe RV dysfunction.

34. Recommendations for Evaluation and
Follow-Up of the Repaired Patient
Class I
1. Pt`s with repaired TOF should have at least annual follow-up with a
cardiologist who has expertise in ACHD. (Level of Evidence: C)
2. Pt`s with TOF should have echocardiographic examinations and/or
MRIs performed by staff with expertise in ACHD. (Level of Evidence:
C)
3. Screening for heritable causes of their condition (eg, 22q11 deletion)
should be offered to all pt`s with TOF. (Level of Evidence: C)
4. Before pregnancy or if a genetic syndrome is identified, consultation
with a geneticist should be arranged for pt`s with TOF. (Level of
Evidence: B)
5. Pt`s with unrepaired or palliated forms of tetralogy should have a
formal evaluation at an ACHD center regarding suitability for repair.
(Level of Evidence: B)

35.  The frequency, although typically annual, may be determined by the
extent and degree of residual abnormalities.
 Appropriate imaging (2D ECHO annually in most cases and/or MRI
every 2 to 3 years) should be undertaken by staff trained in imaging
of complex congenital heart defects.
 An ECG should be performed annually to assess cardiac rhythm and
to evaluate QRS duration.
 Periodic cardiopulmonary testing may be helpful to facilitate serial
follow-up of exercise capacity and to evaluate the potential for
exercise induced arrhythmias.
 Other testing should be arranged in response to clinical problems,
particularly a Holter monitor if there is concern about arrhythmias.

36. Recommendation for Imaging
Class 1
 Comprehensive echo imaging should be performed in a regional ACHD
center to evaluate the anatomy and hemodynamics in pt`s with repaired
TOF . (Level of Evidence: B)
 The presence and severity of residual RVOT obstruction and PR can usually
be assessed along with the presence or absence of TR.
 The TR velocity facilitates measurement of the RV pressure.
 A residual VSD may be seen.
 RV volume and wall motion are not reliably quantified by standard
techniques, although size and function can be determined qualitatively.
 Doppler measurement of the RVMPI useful adjunct for serial assessment
of RV systolic function.
 Atrial size can be assessed.
 Aortic root dilation and AR should be sought and evaluated at regular
intervals.

37.  MRI is now seen as the reference standard for assessment of
RV volume and systolic function.
It can be helpful in assessing the severity of PR and in
evaluating important associated pathology, especially
involving the pulmonary arteries and the ascending aorta.
Left-sided heart disease can also be evaluated.
 CT scan - makes similar measurements of RV volume and
systolic function and is potentially helpful in pt`s who cannot
have an MRI, although bcz of the higher radiation exposure, it
is not suitable for serial measurements.

38. Recommendations for Diagnostic and Interventional
Catheterization for Adults With TOF
Class I
1. Catheterization of adults with TOF should be performed in regional centers
with expertise in ACHD. (Level of Evidence: C)
2. Coronary artery delineation should be performed before any intervention for
the RVOT. (Level of Evidence: C)
Class IIb
1. In adults with repaired TOF, catheterization may be considered to better
define potentially treatable causes of otherwise unexplained LV or RV
dysfunction, fluid retention, chest pain, or cyanosis. In these circumstances,
transcatheter interventions may include:
a. Elimination of residual shunts or aortopulmonary collateral vessels. (Level of
Evidence: C)
b. Dilation (with or without stent implantation) of RVOT obstruction. (Level of
Evidence: B)
c. Elimination of additional muscular or patch margin VSD. (Level of
Evidence: C)
d. Elimination of residual ASD. (Level of Evidence: B)

39. Recommendations for Interventional
Catheterization
Class I
1. Interventional catheterization in an ACHD center is
indicated for patients with previously repaired tetralogy
of Fallot with the following indications:
a. To eliminate residual native or palliative systemic–
pulmonary artery shunts. (Level of Evidence: B)
b. To manage coronary artery disease. (Level of Evidence: B)
Class IIa
1. Interventional catheterization in an ACHD center is
reasonable in patients with repaired tetralogy of Fallot to
eliminate a residual ASD or VSD with a left-to-right shunt
greater than 1.5:1 if it is in an appropriate anatomic
location. (Level of Evidence: C)

40. Diagnostic Catheterization Cont..
 Assessment of hemodynamics
 Assessment of pulmonary blood flow and resistance
 Assessment of the nature of RV outflow or pulmonary artery obstruction
 Delineation of coronary artery origin and course before any interventional
procedure
 Assessment of ventricular function and presence of residual septal
defects, as well as assessment of the degree of mitral regurgitation or AR.
 Assessment of the significance of flow across a PFO or ASD and its
potential elimination
 Performance of coronary angiography, with potential to eliminate
symptomatic obstructive lesions
 Assessment of pulmonary regurgitation and right-sided heart failure.

41. Branch Pulmonary Artery
Angioplasty
 Balloon angioplasty of a branch pulmonary artery results in
intimal and medial dissection and subsequent inflammatory
repair and increase in vessel size.
 Dilation may be considered when RV pressure is more than
50% of the systemic level or at lower pressure when there is
RV dysfunction.
 Balloon PA angioplasty may also be considered when there
is unbalanced pulmonary blood flow greater than 75%,
25%, or otherwise unexplained dyspnea with severe
vascular stenosis.
 PA balloon angioplasty may be an effective way to reduce
obstruction to PBF, thereby increasing PVC and decreasing
PVR.

42. Balloon angioplasty is usually effective for
intermediate-branch pulmonary artery stenoses.
Post deployment anti inflammatory or anti
proliferative/anticoagulant strategies remain undefined.
Stent redilation has been shown to be effective in
selected patients as late as 10 years after implantation.
These techniques has recently been extended to adults
with very distal segmental pulmonary artery stenoses
and appears promising.
The transcatheter approach to the management of
residual muscular or patch margin VSDs.

43. Exercise Testing
 Exercise testing may be used to assess functional
capacity objectively and to evaluate possible
exertional arrhythmias. Serial evaluations may be
helpful.

44. Management Strategy for the
Patient With Prior Repair
Medical Therapy
Most patients need no regular medication in
the absence of significant residual
hemodynamic abnormality.
Heart failure medications may be necessary in
the setting of RV and LV dysfunction.

45. Recommendations for Surgery for Adults
With Previous Repair of TOF
Class I
1. Surgeons with training and expertise in CHD
should perform operations in adults with
previous repair of TOF. (Level of Evidence: C)
2. PVR is indicated for severe PR and symptoms
or decreased exercise tolerance. (Level of
Evidence: B)
3. Coronary artery anatomy, specifically the
possibility of an anomalous LAD across the
RVOT, should be ascertained before operative
intervention. (Level of Evidence: C)

46. Class IIa
1. PVR is reasonable in adults with previous
TOF, severe PR, and any of the following:
a) Moderate to severe RV dysfunction. (Level of
Evidence: B)
b) Moderate to severe RV enlargement. (Level of
Evidence: B)
c) Development of symptomatic or sustained atrial
and/or ventricular arrhythmias. (Level of
Evidence: C)
d) Moderate to severe TR. (Level of Evidence: C)

47. 2.
Collaboration between ACHD surgeons and ACHD
interventional cardiologists, which may include preoperative
stenting, intraoperative stenting, or intraoperative patch
angioplasty, is reasonable to determine the most feasible Tt
for pulmonary artery stenosis. (Level of Evidence: C)

48. 3. Surgery is reasonable in adults with prior repair of TOF and residual RVOT
obstruction (valvular or subvalvular) and any of the following indications:
a. Residual RVOT obstruction (valvular or subvalvular) with peak
instantaneous echocardiography gradient greater than 50 mm Hg. (Level of
Evidence: C)
b. Residual RVOT obstruction (valvular or subvalvular) with RV/LV pressure
ratio greater than 0.7. (Level of Evidence: C)
c. Residual RVOT obstruction (valvular or subvalvular) with progressive
and/or severe dilatation of the right ventricle with dysfunction. (Level of
Evidence: C)
d. Residual VSD with a left-to-right shunt greater than 1.5:1. (Level of
Evidence: B)
e. Severe AR with associated symptoms or more than mild LV dysfunction.
(Level of Evidence: C)
f. A combination of multiple residual lesions (eg, VSD and RVOT obstruction)
leading to RV enlargement or reduced RV function. (Level of Evidence: C)

49. Indications for intervention after repair
of tetralogy of Fallot

51. The need for re-intervention, usually for
pulmonary valve insertion, increases after the
second decade of life.
Pt`s with RV–to–pulmonary artery conduit
repairs often require further intervention for
conduit stenosis or regurgitation.

52. Indications for EP testing and ICD
 EP testing and/or ablation must be considered for symptomatic pt`s with
suspected or documented clinical arrhythmia, atrial or ventricular.
 An ICD should be implanted for sec. prevention of SCD (patients with
cardiac arrest or sustained VT) (IC).
 ICD implantation for pri. prevention remains controversial, and no ideal
risk stratification scheme has so far been developed.
 The following risk markers—although not consistently—have been
reported:
 Right and/or left ventricular dysfunction
 Extensive ventricular fibrosis (on CMR)
 QRS ≥180 ms
 Significant PR
 Non-sustained VT on Holter monitoring
 Inducible VT at EP testing
 Long-lasting palliative shunts
 Older age at time of repair.

53. Key Issues to Evaluate and Follow-Up
 Recommendations for Arrhythmias: Pacemaker/Electrophysiology
Testing
 Class I
1. Annual surveillance with history, ECG, assessment of RV function, and
periodic exercise testing is recommended for patients with
pacemakers/automatic implantable cardioverter defibrillators. (Level of
Evidence: C)
 Class IIa
1. Periodic Holter monitoring can be beneficial as part of routine follow-
up. The frequency should be individualized depending on the
hemodynamics and clinical suspicion of arrhythmia. (Level of Evidence:
C)
 Class IIb
1. Electrophysiology testing in an ACHD center may be reasonable to
define suspected arrhythmias in adults with TOF. (Level of Evidence: C)

54. The 30-year survival rate from reoperations for the first 106
patients undergoing surgical repair was 91%.
Patients with TOF born prior to the early 1970s were often
palliated with systemic artery to pulmonary artery shunts to
increase pulmonary blood flow prior to the definitive repair.

56. Despite overall excellent hemodynamic outcomes after
surgery for TOF, there remains a concerning incidence
of unexpected sudden death during long-term follow-
up .
VT appears to be the mechanism responsible for most
of these events, although rapidly conducted IART (atrial
flutter) or AV block may be responsible in some cases.
The incidence of sudden death for the adult tetralogy
population can be estimated from several large series
to be on the order of 2.5% per decade of follow-up.

57. Estimates of Sudden Death After
Tetralogy of Fallot Surgery

58. Compromised AV conduction, with the hypothesis
that Trauma to AV conduction tissues at the time
of surgery (enough to cause permanent
bifascicular block) could lead to late sudden
death, presumably due to abrupt worsening of
conduction with asystole.
By the 1980s, however, the emphasis shifted
away from AV block toward VT as the more
common mechanism for sudden death in tetralogy
patients.

59. Potential Risk Factors for Sudden Death After TOF Surgery

60. In general high-risk tetralogy pt involves some
combination of-
1. Long-standing palliative shunts
2. Older age at the time of definitive surgery
3. Abnormal RV hemodynamics (due to pulmonary
regurgitation and/or residual outflow obstruction)
4. High-grade ectopy on Holter monitor
5. Inducible VT at electrophysiological study.
6. QRS duration greater than 180 ms.

61. Reproduction
Pregnancy is not advised in patients with unrepaired
TOF.
After repair of TOF, the prognosis for a successful
pregnancy is good provided there are no important
hemodynamic residua and functional capacity is good.
A comprehensive, informed cardiovascular evaluation
is recommended before each pregnancy.
Pregnancy is usually well tolerated even in the setting
of severe pulmonary regurgitation, as long as RV
function is no more than mildly depressed and sinus
rhythm is maintained.

62. Pt`s with TOF have an increased risk of fetal loss, and
their offspring are more likely to have congenital
anomalies than offspring in the general population,
especially in the setting of a 22q11.2 microdeletion.
Screening for 22q11.2 microdeletion should be
considered in pt`s with conotruncal abnormalities
before pregnancy to provide appropriate genetic
counseling.
In the absence of a 22q11 deletion, the risk of a fetus
having CHD is approximately 4% to 6%.
Fetal echocardiography should be offered to the mother
in the second trimester.

63. Endocarditis Prophylaxis
The endocarditis risk in GUCH patients is
substantially higher than in the general
population, with marked variation between
lesions.

64. Oral hygiene and regular dental review have
an essential role in reducing the risk of IE.
Aseptic measures are mandatory during
manipulation of venous catheters and during
any invasive procedure.
It is currently recommended by expert
consensus to limit antibiotic prophylaxis to pts
with the highest risk of IE undergoing the
highest risk procedures (IIaC).

65. † Patients with a prosthetic valve or a prosthetic
material used for cardiac valve repair
† Patients with previous IE
† Patients with CHD: A cyanotic CHD, without surgical
repair, or with residual defects, palliative shunts, or
conduits
A CHD after repair with prosthetic material whether
placed by surgery or by percutaneous technique, up to 6
months after the procedure (until endothelialization)
A when a residual defect persists at the site of
implantation of a prosthetic material or device by
cardiac surgery or percutaneous technique.

66. The recommendation is limited to dental
procedures requiring manipulation of the
gingival or periapical region of the teeth or
perforation of the oral mucosa.
Antibiotics are not recommended for
respiratory tract, gastrointestinal,
genitourinary, dermatological, or
musculoskeletal procedures unless there is an
established infection.

67. THANKYOU