title: Predicting survival in patients receiving continuous flow left ventricular assist devices: the HeartMate II risk score.
abstract: OBJECTIVE
  The aim of this study was to derive and validate a model to predict survival in candidates for HeartMate II (HMII) (Thoratec, Pleasanton, California) left ventricular assist device (LVAD) support.
  
  
  BACKGROUND
  LVAD mortality risk prediction is important for candidate selection and communicating expectations to patients and clinicians. With the evolution of LVAD support, prior risk prediction models have become less valid.
  
  
  METHODS
  Patients enrolled into the HMII bridge to transplantation and destination therapy trials (N = 1,122) were randomly divided into derivation (DC) (n = 583) and validation cohorts (VC) (n = 539). Pre-operative candidate predictors of 90-day mortality were examined in the DC with logistic regression, from which the HMII Risk Score (HMRS) was derived. The HMRS was then applied to the VC.
  
  
  RESULTS
  There were 149 (13%) deaths within 90 days. In the DC, mortality (n = 80) was higher in older patients (odds ratio [OR]: 1.3, 95% confidence interval [CI]: 1.1 to 1.7 per 10 years), those with greater hypoalbuminemia (OR: 0.49, 95% CI: 0.31 to 0.76 per mg/dl of albumin), renal dysfunction (OR: 2.1, 95% CI: 1.4 to 3.2 per mg/dl creatinine), coagulopathy (OR: 3.1, 95% CI: 1.7 to 5.8 per international normalized ratio unit), and in those receiving LVAD support at less experienced centers (OR: 2.2, 95% CI: 1.2 to 4.4 for <15 trial patients). Mortality in the DC low, medium, and high HMRS groups was 4%, 16%, and 29%, respectively (p < 0.001). In the VC, corresponding mortality was 8%, 11%, and 25%, respectively (p < 0.001). HMRS discrimination was good (area under the receiver-operating characteristic curve: 0.71, 95% CI: 0.66 to 0.75).
  
  
  CONCLUSIONS
  The HMRS might be useful for mortality risk stratification in HMII candidates and may serve as an additional tool in the patient selection process.
authors.affiliation: University of Michigan Health System, Ann Arbor, Michigan 48109-5853, USA. jennmatt@med.umich.edu
authors.forename: Jennifer
authors.initials: J
authors.lastname: Cowger
authors.forename: Kartik
authors.initials: K
authors.lastname: Sundareswaran
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Rogers
authors.forename: Soon J
authors.initials: SJ
authors.lastname: Park
authors.forename: Francis D
authors.initials: FD
authors.lastname: Pagani
authors.forename: Geetha
authors.initials: G
authors.lastname: Bhat
authors.forename: Brian
authors.initials: B
authors.lastname: Jaski
authors.forename: David J
authors.initials: DJ
authors.lastname: Farrar
authors.forename: Mark S
authors.initials: MS
authors.lastname: Slaughter
mesh_terms: D000368:Aged; D005260:Female; D006333:Heart Failure / Q000401:mortality* / Q000601:surgery*; D006353:Heart-Assist Devices; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018579:Patient Selection; D011358:Product Surveillance, Postmarketing; D011379:Prognosis; D012372:ROC Curve; D018570:Risk Assessment; D016019:Survival Analysis