title: Modified Blalock Taussig shunt: a not-so-simple palliative procedure.
abstract: OBJECTIVE
  Thirty-two consecutive isolated modified Blalock Taussig (BT) shunts performed in infancy since 2004 were reviewed and analysed to identify the risk factors for shunt intervention and mortality.
  
  
  METHODS
  Sternotomy was the only approach used. Median age and weight were 10.5 (range 1-74) days and 2.9 (1.9-4.4) kg, respectively. Shunt palliation was performed for biventricular hearts (Tetralogy of Fallot/double outlet right ventricle/transposition of great arteries_ventricular septal defect_pulmonary stenosis/pulmonary atresia_ventricular septal defect/others) in 21, and univentricular hearts in 11, patients. Hypoplastic left heart syndrome patients were excluded. Two procedures required cardiopulmonary bypass. Median shunt size was 3.5 (3-4) mm and median shunt size/kg body weight was 1.2 (0.9-1.7) mm/kg. Reduction in shunt size was necessary in 5 of 32 (16%) patients.
  
  
  RESULTS
  Three of 32 (9%) patients died after 3 (1-15) days due to cardiorespiratory decompensation. Lower body weight (P = 0.04) and bigger shunt size/kg of body weight (P = 0.004) were significant risk factors for mortality. Acute shunt thrombosis was observed in 3 of 32 (9%), none leading to death. Need for cardiac decongestive therapy was associated with univentricular hearts (P < 0.001), bigger shunt size (P = 0.054) and longer hospital stay (P = 0.005). Twenty-eight patients have undergone a successful shunt takedown at a median age of 5.5 (0.5-11.9) months, without late mortality.
  
  
  CONCLUSIONS
  Palliation with a modified BT shunt continues to be indicated despite increased thrust on primary corrective surgery. Though seemingly simple, it is associated with significant morbidity and mortality. Effective over-shunting and acute shunt thrombosis are the lingering problems of shunt therapy.
authors.affiliation: Division of Congenital Cardiovascular Surgery, University Children's Hospital Zurich, Zurich, Switzerland.
authors.forename: Verena
authors.initials: V
authors.lastname: Dirks
authors.forename: René
authors.initials: R
authors.lastname: Prêtre
authors.forename: Walter
authors.initials: W
authors.lastname: Knirsch
authors.forename: Emanuela R
authors.initials: ER
authors.lastname: Valsangiacomo Buechel
authors.forename: Burkhardt
authors.initials: B
authors.lastname: Seifert
authors.forename: Martin
authors.initials: M
authors.lastname: Schweiger
authors.forename: Michael
authors.initials: M
authors.lastname: Hübler
authors.forename: Hitendu
authors.initials: H
authors.lastname: Dave
mesh_terms: D058366:Blalock-Taussig Procedure / Q000009:adverse effects / Q000379:methods*; D001835:Body Weight; D005260:Female; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010166:Palliative Care / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D056346:Sternotomy; D013908:Thoracotomy
keywords: Cyanotic heart disease; Modified Blalock Taussig shunt; Mortality; Palliation