Bidirectional Cavo-pulmonary Anastomosis

1. Bidirectional Cavo-pulmonary Anastomosis Seoul National University Hospital Department of Thoracic & Cardiovascular Surgery

2. Major Concerns of BCPC 1. Time of BCPC • 3~6 months of age 2. Time of complete palliation • 2~3 years of age 3. Pulmonary A-V malformation • 1) Duration of BCPC (within 2~3 years) • 2) Time of BCPC (age of less than 2months old) • 3) Isomerism (left) and heterotaxy syndrome • 4) Extra source of pulmonary blood flow

3. 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

4. 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

5. 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

6. 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

7. 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

8. Inadequate Oxygenation after BCPC • Elevated PVR • Pulmonary venous obstruction • Progression of AV valve regurgitation • Progression of ventricular dysfunction

9. 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.

10. 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.

11. 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

12. Hemi-Fontan Operation

13. Hemi-Fontan OperationAlternative Method

14. Bidirectional Cavopulmonary Connection BCPC

15. BCPC. Operative View BCPC

16. Before BCPC. Operative View • Diagnosis ; Tricuspid atresia, Ib , 3 months old SVC

17. BCPC. Operative View BCPC

18. BCPC. Operative View BCPC

19. 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

20. Pulmonary Arteriovenous Malformations • VEGF = vascular endothelial growth factor

21. Pulmonary Arteriovenous Malformation