Blalock-Taussig (BT) Shunt — Cost, Top Hospitals & Success Rates | MyMedicPlus

The Blalock-Taussig (BT) shunt is a palliative cardiac surgical procedure that creates an artificial conduit between a systemic artery — typically the subclavian artery — and the ipsilateral pulmonary artery, thereby increasing pulmonary blood flow (blood flow to the lungs) in neonates and infants with cyanotic congenital heart defects characterised by reduced pulmonary circulation. It is one of the most historically significant operations in congenital cardiac surgery, first performed by Alfred Blalock and Helen Taussig at Johns Hopkins Hospital in 1944, and remains an essential palliation procedure in paediatric cardiac surgery today.

The modified BT shunt (mBTS), introduced by de Leval in 1981, uses a polytetrafluoroethylene (PTFE, Gore-Tex) tube graft to connect the subclavian or innominate artery to the pulmonary artery, providing a controlled and predictable shunt diameter compared with the original direct anastomosis technique. The standard graft sizes used are 3.5 mm for neonates and 4 mm for larger infants. The procedure is performed via a lateral thoracotomy or median sternotomy, typically without cardiopulmonary bypass (off-pump), and usually takes two to three hours.

The BT shunt is a staging procedure, not a corrective operation — it sustains life and allows somatic growth until the child is large enough and the cardiac anatomy is suitable for a definitive corrective or second-stage palliative procedure (such as Glenn shunt or Fontan completion). In centres managing complex congenital heart disease, shunt surgery is a cornerstone of the staged repair strategy.

The BT shunt is used in cyanotic congenital heart defects where restricted pulmonary blood flow causes severe hypoxaemia (low blood oxygen saturation), typically presenting as neonatal cyanosis. The most common indication is pulmonary atresia with intact ventricular septum (PA-IVS) or pulmonary atresia with ventricular septal defect (PA-VSD), where the pulmonary artery is absent or atretic and the lungs are entirely dependent on a patent ductus arteriosus (PDA) for blood supply. When the PDA closes naturally after birth, these infants rapidly deteriorate and require urgent intervention.

Other indications include tetralogy of Fallot (ToF) with severe pulmonary stenosis in neonates not suitable for early total repair, tricuspid atresia with reduced pulmonary blood flow, double outlet right ventricle with pulmonary stenosis, and some cases of hypoplastic left heart syndrome as part of the staged Norwood palliation pathway. The common thread is inadequate native pulmonary blood flow causing life-threatening hypoxaemia. Prior to definitive repair, prostaglandin E1 infusion is used to maintain PDA patency while the shunt is planned and inserted.

Neonates and infants with confirmed duct-dependent pulmonary circulation or significantly reduced native pulmonary blood flow causing hypoxaemia (SpO2 below 70 to 75% despite prostaglandin therapy) are candidates for BT shunt placement. Echocardiographic diagnosis of the underlying anatomy is performed urgently, and catheter-based haemodynamic evaluation may be performed in centres with paediatric cardiac catheterisation facilities. The decision for BT shunt versus alternative interventions (catheter-based pulmonary balloon valvuloplasty, primary total repair) is made by the paediatric cardiac surgery team based on anatomy, centre expertise, and patient stability.

Contraindications to BT shunt include pulmonary arterial anatomy that precludes safe anastomosis (severely hypoplastic or absent pulmonary arteries), haemodynamic instability precluding off-pump surgery, and specific anatomical configurations better served by alternative shunting strategies (central aortopulmonary shunt, Sano modification with RVPA conduit in Norwood palliation). Premature neonates with inadequate body weight (typically below 2 kg) have higher shunt-related mortality and may be managed with prolonged prostaglandin therapy until larger.

The modified BT shunt (Gore-Tex PTFE tube graft) is the standard technique, performed via a right or left lateral thoracotomy depending on the sidedness of the aortic arch and pulmonary anatomy. A Gore-Tex graft (3.5 to 4 mm for neonates, 4 to 5 mm for older infants) is sutured end-to-side from the innominate or subclavian artery to the ipsilateral pulmonary artery. Intraoperative transoesophageal echocardiography or direct pressure measurement confirms adequate shunt flow and acceptable oxygen saturation post-shunt.

Alternative palliative shunting procedures include the central shunt (ascending aorta to main pulmonary artery), which provides bilateral pulmonary blood flow but requires median sternotomy. In Norwood palliation for hypoplastic left heart syndrome, the Sano modification uses a RVPA conduit (right ventricle to pulmonary artery) rather than a BT shunt to provide pulmonary circulation, offering more stable physiology in some analyses. Catheter-based interventions including pulmonary balloon valvuloplasty and ductal stenting are increasingly used as alternatives to surgical shunting at specialist paediatric interventional cardiology centres, allowing deferral or avoidance of surgery in selected anatomies. Percutaneous stent-based palliation with ductal stenting or branch pulmonary artery stenting, now available in experienced interventional cardiology centres, allowing deferral or avoidance of surgery in selected anatomies. The choice between surgical and interventional palliation is made by the congenital heart multidisciplinary team based on anatomy, patient weight, and institutional expertise to optimise the pathway to biventricular repair.

The BT shunt is a life-saving procedure in the neonate with duct-dependent pulmonary circulation. Following successful shunt insertion, oxygen saturation typically improves to 75 to 85% — a clinically appropriate target for balanced systemic-pulmonary circulation — allowing the infant to grow and achieve the weight and somatic development required for subsequent staged repair. Without the shunt, these infants would die within days to weeks of PDA closure.

Post-shunt survival to the subsequent stage of repair (Glenn anastomosis at four to six months of age) is approximately 80 to 90% at high-volume specialist paediatric cardiac surgery centres. Shunt occlusion — the most feared early complication — occurs in approximately 5 to 10% of neonatal shunts and is managed by emergent catheter-based or surgical revision. For patients who successfully complete staged palliation through Glenn shunt and Fontan completion, long-term survival with a single-ventricle circulation is increasingly well-documented, with 20-year survival now exceeding 70% at specialist centres.

BT shunt surgery in critically ill neonates carries significant procedural risk. Early mortality is 3 to 10% at specialist centres and higher at lower-volume centres, reflecting the physiological vulnerability of neonates with complex cardiac defects. The most dangerous early complication is shunt thrombosis (clotting of the graft) causing acute loss of pulmonary blood flow, severe hypoxaemia, and cardiovascular collapse — this is a surgical emergency requiring urgent revision or thrombolysis. All neonates with BT shunts receive aspirin 1 to 5 mg/kg/day for antiplatelet therapy, and some centres use heparin or low-molecular-weight heparin in the early post-operative period.

Too much shunt flow causes cardiac volume overload and pulmonary flooding (congestive heart failure), while too little flow causes persistent cyanosis — choosing the correct shunt diameter is a balance requiring intraoperative assessment. Diaphragmatic palsy from phrenic nerve injury occurs in approximately 3 to 8% of cases and may prolong ventilator weaning. Pulmonary artery distortion at the anastomosis site can complicate subsequent surgical procedures, requiring careful technique at the time of BT shunt and at subsequent stages. Wound infection and dehiscence are uncommon but more significant in neonates than in adults.

Post-operative care is provided in the paediatric cardiac intensive care unit (PCICU) with continuous monitoring of oxygen saturation, cardiac output, haemodynamics, and shunt function. Most neonates require five to fourteen days in intensive care post-BT shunt before transfer to the cardiac ward and eventual discharge. Nasal oxygen is often needed for weeks after discharge. Aspirin is continued until the shunt is taken down at the subsequent surgical stage.

Outpatient follow-up with the paediatric cardiologist occurs monthly for the first six months, with echocardiography at each visit to assess shunt patency, pulmonary artery growth, and ventricular function. Catheter-based cardiac catheterisation is typically performed three to four months after BT shunt to assess pulmonary artery anatomy and haemodynamics before planning the Glenn procedure. Families receive detailed written guidance on warning signs of shunt thrombosis (acute profound cyanosis, unresponsiveness) requiring immediate emergency evaluation.

BT shunt surgery for neonatal cyanotic congenital heart disease in the United States costs $80,000 to $200,000 including PCICU care, typically covered by Medicaid or private insurance as a medically necessary procedure for paediatric cardiac conditions. In the UK, NHS provides all congenital heart surgery free at specialist paediatric cardiac centres. The cost burden falls primarily on families in countries without universal health coverage or adequate national health infrastructure for paediatric cardiac surgery.

Medical tourism for paediatric congenital heart surgery is a significant global healthcare issue, as many families in lower-income countries travel to specialist centres in India, Thailand, Turkey, and China where paediatric cardiac surgery is available at substantially lower cost. Leading paediatric cardiac centres in India — including AIIMS, SRCC Children's Hospital, Narayana Health, and Apollo Children's Hospital — have substantial expertise in complex congenital heart surgery including BT shunts and subsequent staged palliation, with costs of $5,000 to $15,000 for complete surgical management. Families should verify centre volume (high-volume centres have better outcomes) and the availability of a dedicated PCICU.

Prostaglandin E1 (PGE1) intravenous infusion maintains PDA patency in duct-dependent neonates and is the immediate life-saving temporising measure used while planning surgical or catheter-based intervention. PGE1 infusion cannot be maintained indefinitely as tolerance develops and complications (apnea, hypotension, pyrexia) limit long-term use, but it provides days to weeks of stabilisation.

Catheter-based alternatives to BT shunt include ductal stenting (placement of a coronary stent in the PDA to maintain it open, avoiding thoracotomy) and pulmonary balloon valvuloplasty for selected cases of pulmonary stenosis with adequate pulmonary valve anatomy. Ductal stenting is increasingly performed at experienced paediatric interventional centres as an alternative to surgical shunting in selected anatomies, with comparable medium-term outcomes and shorter procedural recovery, though the PDA may be anatomically unsuitable for stenting in some patients. Primary total repair (correcting the underlying defect in one surgery rather than staged palliation) is appropriate for selected diagnoses at expert centres but requires favourable anatomy and adequate patient size.