title: Development of a Transplantation Risk Index in Patients With Mechanical Circulatory Support: A Decision Support Tool.
abstract: OBJECTIVE
  The aim of this study was to develop a risk index specific to patients on mechanical circulatory support that accurately predicts 1-year mortality after orthotopic heart transplantation using the United Network for Organ Sharing database.
  
  
  BACKGROUND
  Few clinical tools are available to aid in the decision between continuing long-term device support and performing transplantation in patients bridging with mechanical circulatory support.
  
  
  METHODS
  Using a prospectively collected, open cohort, 6,036 patients receiving mechanical circulatory support who underwent orthotopic heart transplantation between 2000 and 2013 were evaluated and randomly separated into derivation (80%) and validation (20%) groups. Multivariate logistic regression models were constructed using variables that improved the explanatory power of the model, which was determined using multiple methods. Points for a simple additive risk index were apportioned on the basis of relative effect on odds of 1-year mortality.
  
  
  RESULTS
  A 75-point scoring system was created from 9 recipient and 4 donor variables. The average score in the validation cohort was 14.4 ± 7.7, and scores ranged from 0 to 57; these values were similar to those in the derivation cohort. Each 1-point increase predicted an 8.3% increase in the odds of 1-year mortality (odds ratio: 1.08; 95% confidence interval: 1.06 to 1.11). Low (0 to 10), intermediate (11 to 20), and high (>20) risk score cohorts were created, with predicted average 1-year mortalities of 8.6%, 12.8%, and 31%, respectively, in the validation cohort.
  
  
  CONCLUSIONS
  The investigators present a novel, internally cross-validated risk index that accurately predicts mortality in bridge-to-transplantation patients.
authors.affiliation: Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland; Division of Thoracic and Cardiovascular Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Lily E
authors.initials: LE
authors.lastname: Johnston
authors.affiliation: Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Joshua C
authors.initials: JC
authors.lastname: Grimm
authors.affiliation: Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: J Trent
authors.initials: JT
authors.lastname: Magruder
authors.affiliation: Department of Cardiac Surgery, Vanderbilt University Medical Center, Nashville, Tennessee. Electronic address: ashish.s.shah@vanderbilt.edu.
authors.forename: Ashish S
authors.initials: AS
authors.lastname: Shah
mesh_terms: D020000:Decision Support Systems, Clinical; D005112:Extracorporeal Circulation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality / Q000601:surgery*; D016027:Heart Transplantation / Q000379:methods* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology
keywords: cardiac transplantation; mechanical circulatory support; risk modeling