Bidirectional Cavo-pulmonary Anastomosis

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Bidirectional Cavo-pulmonary Anastomosis

• Seoul National University Hospital
• Department of Thoracic Cardiovascular Surgery

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Major Concerns of BCPC

• 1. Time of BCPC
• 36 months of age
• 2. Time of complete palliation
• 23 years of age
• 3. Pulmonary A-V malformation
• 1) Duration of BCPC (within 23 years)
• 2) Time of BCPC (age of less than 2months old)
• 3) Isomerism (left) and heterotaxy syndrome
• 4) Extra source of pulmonary blood flow

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SVC Flow to Total Cardiac Output

• 1. At birth 50 of total cardiac output
• 2. At 2 years 59 of total cardiac output
• 3. At 6 years 35 of total cardiac output
• 4. At adult 1/3 of total cardiac output

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Advantages of Bidirectional CP Shunt

• 1. Relief of volume load
• 2. Improve of ventricular AV valve function
• 3. Avoidance of pulmonary arterial distortion
• 4. Simplification of eventual Fontan procedure
• 5. Prevention of pulmonary vascular disease

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Advantages Disadvantages of BCPS

• 1. Advantages
• 1) Increase effective PBF
• 2) Decrease cardiac volume overload
• 3) Maintain PA shape
• 4) Decrease PVOD
• 5) Correct the associated cardiac anomalies
• (PA distortion, AVV regurgitation. VSD
  extension, DKS, ASO, )
• 2. Disadvantages
• 1) Decrease PBF with aging
• 2) Retarded PA development
• 3) Pulmonary AV fistula
• 4) Venovenous collateral circulation
• 5) Abnormal distribution of PBF
• 6) Additional risks due to secondary
  operation

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Ventricular Function after BCPC

• 1. Immediate decrease in the cavity size
• 2. Concomitant increase in wall thickness
• 3. Reduction in myocardial wall stress or
• afterload reduction

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Collaterals after BCPC

• Risk factors for development
• Subnormal oxygen content
• Decreased or nearly absent pulsatility
• Decreased absolute volume velocity of flow
• Lack of hepatic venous effluent

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Inadequate Oxygenation after BCPC

1. Elevated PVR
2. Pulmonary venous obstruction
3. Progression of AV valve regurgitation
4. Progression of ventricular dysfunction

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Improving Oxygenation after BCPC

• Increase systemic cardiac output to increase the
  saturation of IVC
• Ventilatory manipulation
• Additional source of pulmonary blood flow (small
  systemic to pulmonary artery shunt)
• The shunt will defeat one of the
  objectives
• of the BCPS.

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BCPC with Accessory Pulsatile Flow

• Surgeon must be aware of potential beneficial
  influence
• on pulmonary vascular development and
  deleterious
• impact by imposing a volume load on the
  ventricle.
• Volume load
• Pulmonary hypertension
• Morbidity mortality
• Bidirectional Glenn allows single ventricle to
  adapt remodel in accordance with the reduced
  volume loading
• with a consequently much reduced risk of
  mortality.

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Auxilliary Pulmonary Flow on BCPC

• Aim
• 1) Promoting pulmonary arterial growth
• 2) Preventing arteriovenous fistulas
• Indication
• 1) PaO2 less than 30 mmHg
• 2) Older patients (beyond the toddler stage)
• 3) Antegrade flow by banding or tightening
• Results
• 1) Increased arterial O2 saturation
• 2) Increased morbidity mortality

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Hemi-Fontan Operation
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Hemi-Fontan OperationAlternative Method
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Bidirectional Cavopulmonary Connection
BCPC
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BCPC. Operative View
BCPC
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Before BCPC. Operative View
SVC

• Diagnosis Tricuspid atresia, Ib , 3 months old

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BCPC. Operative View
BCPC
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BCPC. Operative View
BCPC
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Pulmonary Arteriovenous Malformations

• The role of angiogenesis in PAVM development
• The liver is known to produce precursors of
  angiogenesis inhibitors.
• Collagen XVIII and plasminogen are produced in
  large quantities by the liver and secreted into
  hepatic venous effluent where subsequent action
  by proteolytic enzymes cleaves these precursors
  into the potent angiogenesis inhibitors
  endostatin and angiostatin, respectively.
• Exclusion of these substances from the pulmonary
  arterial circulation after cavopulmonary
  anastomosis may result in vascular proliferation

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Pulmonary Arteriovenous Malformations

• VEGF vascular endothelial growth factor

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Pulmonary Arteriovenous Malformation