title: Changing trends in mechanical circulatory assistance:.
abstract: BACKGROUND
  The success of long-term implantable ventricular assist devices has led to their increased use in patients previously thought to be unsuitable for mechanical support. As a result, the demographic profile of patients presenting for LVAD support has changed over time. We reviewed our institutional experience to identify emerging risk factors and changing trends in patients who received the HeartMate VE LVAD.
  
  
  METHODS
  The clinical records were reviewed of 131 consecutive LVAD recipients between 1996 and 2001. All perioperative data were collected prospectively and entered into an institutional database. All patients received a preoperative risk stratification score based upon published criteria. The cohort was arbitrarily divided into early (n = 45), mid (n = 45), and late groups (n = 41).
  
  
  RESULTS
  Overall operative mortality was 25% with no difference between groups. The mean risk score increased significantly over time (early 3.5 +/- 0.4 vs. late 5.3 +/- 0.3, p < 0.05). The proportion of patients at high risk for mortality (score >5) was significantly higher in the late group (51% vs. 29%, p < 0.05). Although ventilation time and ICU stay was similar for all groups, hospital stay was longer in the late group (43 days vs. 23 days, p < 0.05). Mean duration of support fell from 90 to 59 days, but this failed to achieve statistical significance. Out-patient therapy decreased from 73% in the early group to 15% in the late group (p < 0.001). Multivariate analysis identified right heart failure (odds ratio 4.1, 95% CI 2-11) and risk score (OR 1.4, 95% CI 1.2-1.6) as independent predictors of death.
  
  
  CONCLUSIONS
  Despite an increasingly high risk patient population, the mortality associated with LVAD therapy has remained constant. Duration of LVAD support has decreased with a trend toward transplantation before hospital discharge. These data continue to support the aggressive institution of mechanical assistance for acute or chronic heart failure.
authors.affiliation: Division of Cardiovascular Surgery, Toronto General Hospital, University of Toronto, Toronto, Canada.
authors.forename: Vivek
authors.initials: V
authors.lastname: Rao
authors.forename: Mehmet C
authors.initials: MC
authors.lastname: Oz
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Flannery
authors.forename: Katharine A
authors.initials: KA
authors.lastname: Idrissi
authors.forename: Michael
authors.initials: M
authors.lastname: Argenziano
authors.forename: Niloo M
authors.initials: NM
authors.lastname: Edwards
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Naka
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006333:Heart Failure / Q000401:mortality / Q000601:surgery*; D016027:Heart Transplantation; D006353:Heart-Assist Devices / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis