title: Decision tree for adjuvant right ventricular support in patients receiving a left ventricular assist device.
abstract: BACKGROUND
  Right ventricular (RV) failure is a significant complication after implantation of a left ventricular assist device (LVAD). It is therefore important to identify patients at risk a priori. However, prognostic models derived from multivariate analyses have had limited predictive power.
  
  
  METHODS
  This study retrospectively analyzed the records of 183 LVAD recipients between May 1996 and October 2009; of these, 27 later required a RVAD (RVAD(+)) and 156 remained on LVAD only (RVAD(-)) until transplant or death. A decision tree model was constructed to represent combinatorial non-linear relationships of the pre-operative data that are predictive of the need for RVAD support.
  
  
  RESULTS
  An optimal set of 8 pre-operative variables were identified: transpulmonary gradient, age, right atrial pressure, international normalized ratio, heart rate, white blood cell count, alanine aminotransferase, and the number of inotropic agents. The resultant decision tree, which consisted of 28 branches and 15 leaves, identified RVAD(+) patients with 85% sensitivity, RVAD(-) patients with 83% specificity, and exhibited an area under the receiver operating characteristic curve of 0.87.
  
  
  CONCLUSIONS
  The decision tree model developed in this study exhibited several advantages compared with existing risk scores. Quantitatively, it provided improved prognosis of RV support by encoding the non-linear, synergic interactions among pre-operative variables. Because of its intuitive structure, it more closely mimics clinical reasoning and therefore can be more readily interpreted. Further development with additional multicenter, longitudinal data may provide a valuable prognostic tool for triage of LVAD therapy and, potentially, improve outcomes.
authors.affiliation: Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15219, USA.
authors.forename: Yajuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Marc A
authors.initials: MA
authors.lastname: Simon
authors.forename: Pramod
authors.initials: P
authors.lastname: Bonde
authors.forename: Bronwyn U
authors.initials: BU
authors.lastname: Harris
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Teuteberg
authors.forename: Robert L
authors.initials: RL
authors.lastname: Kormos
authors.forename: James F
authors.initials: JF
authors.lastname: Antaki
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D003663:Decision Trees; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000601:surgery; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D018487:Ventricular Dysfunction, Left / Q000601:surgery*; D018497:Ventricular Dysfunction, Right / Q000209:etiology* / Q000601:surgery