ABSTRACT
A systemic to PA shunt is created to improve PBF in patients with right-to-left shunts with reduced PBF, such as tricuspid atresia, pulmonary atresia or those with TOF not suitable for early complete correction. The classical Blalock-Taussig shunt involves an end-to-side anastomosis of the subclavian artery to the ipsilateral PA. A modified Blalock-Taussig shunt utilizes a 3.5 or 4.0 mm polytetrafluoroethylene (PTFE) tube graft,
and is now the procedure of choice. The shunt involves an end-to-side anastomosis of the tube graft to the subclavian or innominate artery and the ipsilateral branch PA. To prevent occlusion of the duct whilst performing the anastomosis, the shunt is placed on the side opposite the aortic arch, therefore usually the right. The shunt is most frequently constructed via a thoracotomy but with hemodynamic instability a median sternotomy and CPB may be required. The shunt usually provides adequate PBF for some months before proceeding to either a full correction for those with TOF or a cavopulmonary shunt in patients with a functional single ventricle such as tricuspid atresia or pulmonary atresia with intact ventricular septum.
