title: Disease-specific outcome analysis of palliation with the modified Blalock-Taussig shunt.
abstract: BACKGROUND
  Albeit being a simple surgical procedure, adverse outcomes with the modified Blalock-Taussig shunt (MBTS) are commonly reported in generalizing terms, independent of the underlying heart disorder.
  
  
  METHODS
  From August 1995 to December 2013, a total of 150 children underwent an MBTS for tetralogy of Fallot (TOF; n = 44, 29%), pulmonary atresia with ventricular septal defect (PA/VSD; n = 28, 19%), pulmonary atresia with intact ventricular septum (PA/IVS; n = 17, 11%), transposition of the great arteries with ventricular septal defect (TGA/VSD) with pulmonary stenosis (PS; n = 12, 8%), Ebstein malformation (n = 2, 1%), and complex univentricular anomalies (n = 47, 31%). Outcome analysis focused on operative mortality and survival until shunt takedown, adjusted to the underlying disease.
  
  
  RESULTS
  In-hospital mortality was 8.7% (n = 13), and interstage mortality was 5.1% (n = 7), resulting in 86.1% survival to the next surgery. Hospital mortality was 14% in PA/VSD, 13% in univentricular heart, and 18% in PA/IVS, while no mortality was observed in TOF, TGA/VSD/PS, and Ebstein disease. A shunt-related complication was observed in 18% (n = 27) of the children, including acute thrombosis (n = 7, 5%), shunt stenosis (n = 3, 2%), overshunting (n = 7, 5%), and pulmonary artery stenosis (n = 10, 7%). Multivariate analysis of shunt-dependent time survival identified a shunt complication occurring in a univentricular circulation (hazard ratio [HR] 4.10, 95% confidence interval [CI] = 1.05-17.43, P = .01) and increased shunt size-to-weight ratio (HR 2.72, 95% CI = 0.80-9.18, P = .04) as risk factors. Shunt thrombosis was also a negative outcome predictor in PA/VSD, when requiring associated unifocalization (P = .05).
  
  
  CONCLUSIONS
  This study shows that the outcome of palliation with the MBTS is importantly affected by the occurrence of a shunt-related complication, whose circulatory effect is even more dismal in single ventricle hearts. Since an increased shunt size-to-weight ratio additionally compromises the shunt-dependent survival, it emphasizes that the choice of the shunt with regard to size as well as surgical approach remains critical.
authors.affiliation: Department of Cardiac Surgery, University Hospital of Ghent, Ghent, Belgium thierry.bove@ugent.be.
authors.forename: Thierry
authors.initials: T
authors.lastname: Bove
authors.affiliation: Department of Pediatric Cardiology, University Hospital of Ghent, Ghent, Belgium.
authors.forename: Kristof
authors.initials: K
authors.lastname: Vandekerckhove
authors.affiliation: Department of Pediatric Cardiology, University Hospital of Ghent, Ghent, Belgium.
authors.forename: Joseph
authors.initials: J
authors.lastname: Panzer
authors.affiliation: Department of Pediatric Cardiology, University Hospital of Ghent, Ghent, Belgium.
authors.forename: Katya
authors.initials: K
authors.lastname: De Groote
authors.affiliation: Department of Pediatric Cardiology, University Hospital of Ghent, Ghent, Belgium.
authors.forename: Daniel
authors.initials: D
authors.lastname: De Wolf
authors.affiliation: Department of Cardiac Surgery, University Hospital of Ghent, Ghent, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: François
mesh_terms: D058366:Blalock-Taussig Procedure / Q000379:methods* / Q000401:mortality; D005260:Female; D006330:Heart Defects, Congenital / Q000401:mortality / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010166:Palliative Care / Q000379:methods*; D011183:Postoperative Complications; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Blalock-Taussig shunt; palliation; survival