title: Changes in renal function after implantation of continuous-flow left ventricular assist devices.
abstract: OBJECTIVE
  The aim of this study was to determine renal outcomes after left ventricular assist device (LVAD) implantation.
  
  
  BACKGROUND
  Renal dysfunction before LVAD placement is frequent, and it is unclear whether it is due to primary renal disease or to poor perfusion.
  
  
  METHODS
  A retrospective single-center analysis was conducted in 83 consecutive patients implanted with HeartMate II continuous-flow LVADs (Thoratec Corp., Pleasanton, California). Calculated glomerular filtration rate (GFR) was assessed on admission and 1, 3, and 6 months after implantation. To define predictors for improvement in GFR, clinical variables were examined in patients with decreased renal function (GFR <60 ml/min/1.73 m(2)) before LVAD, surviving and dialysis-free at 1 month (n = 44).
  
  
  RESULTS
  GFR significantly increased from admission (53.2 ± 21.4 ml/min/1.73 m(2)) to 1 month after LVAD implantation (87.4 ± 27.9 ml/min/1.73 m(2)) (p < 0.0001). Subsequently, at 3 and 6 months, GFR remained significantly (p < 0.0001) above pre-LVAD values. Of the 51 patients with GFRs <60 ml/min/1.73 m(2) before LVAD surviving at 1 month, 34 (67%) improved to GFRs >60 ml/min/1.73 m(2). Univariate pre-operative predictors for improvement in renal function at 1 month included younger age (p = 0.049), GFR improvement with optimal medical therapy (p < 0.001), intra-aortic balloon pump use (p = 0.004), kidney length above 10 cm (p = 0.023), no treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (p = 0.029), higher bilirubin (p = 0.002), higher Lietz-Miller score (p = 0.019), and atrial fibrillation (p = 0.007). Multivariate analysis indicated pre-operative improved GFR (slope = 0.5 U per unit improved; 95% confidence interval: 0.2 to 0.8; p = 0.003), atrial fibrillation (slope = 27; 95% confidence interval: 8 to 46; p = 0.006), and intra-aortic balloon pump use (slope = 14; 95% confidence interval: 2 to 26; p = 0.02) as independent predictors.
  
  
  CONCLUSIONS
  In most patients with end-stage heart failure considered for LVAD implantation, renal dysfunction is reversible and likely related to poor renal perfusion.
authors.affiliation: Department of Cardiovascular Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Tal
authors.initials: T
authors.lastname: Hasin
authors.forename: Yan
authors.initials: Y
authors.lastname: Topilsky
authors.forename: John A
authors.initials: JA
authors.lastname: Schirger
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Li
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zhao
authors.forename: Barry A
authors.initials: BA
authors.lastname: Boilson
authors.forename: Alfredo L
authors.initials: AL
authors.lastname: Clavell
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Rodeheffer
authors.forename: Robert P
authors.initials: RP
authors.lastname: Frantz
authors.forename: Brooks S
authors.initials: BS
authors.lastname: Edwards
authors.forename: Naveen L
authors.initials: NL
authors.lastname: Pereira
authors.forename: Lyle
authors.initials: L
authors.lastname: Joyce
authors.forename: Richard
authors.initials: R
authors.lastname: Daly
authors.forename: Soon J
authors.initials: SJ
authors.lastname: Park
authors.forename: Sudhir S
authors.initials: SS
authors.lastname: Kushwaha
mesh_terms: D000368:Aged; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D006353:Heart-Assist Devices; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011182:Postoperative Care; D011237:Predictive Value of Tests; D011300:Preoperative Care; D051437:Renal Insufficiency / Q000150:complications / Q000175:diagnosis* / Q000401:mortality; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome