title: Anemia and its association with clinical outcome in heart failure patients undergoing cardiac resynchronization therapy.
abstract: OBJECTIVE
  Although a substantial proportion of patients with heart failure (HF) have anemia, there is a paucity of data evaluating the impact of anemia on clinical outcome in CRT patients. Our goal was to examine the ability of baseline hemoglobin (Hb) level and change in Hb level over time to predict clinical 2-year outcome and echocardiographic response to CRT.
  
  
  METHODS
  Three hundred consecutive CRT patients (median 72 years [interquartile range (IQR) 16 years], 19% female) with baseline and follow-up hematological profiles available were examined. Baseline anemia was defined as Hb <12 g/dL in women and <13 g/dL in men, and patients were grouped into equal quartiles based on change in Hb. Two-year clinical outcome was determined using a composite endpoint that included HF hospitalization, left ventricular assist device (LVAD) placement, heart transplantation, and all-cause mortality. Echocardiographic reverse remodeling was examined at 6-month follow-up.
  
  
  RESULTS
  One hundred fifty-one anemic patients were compared to 149 non-anemic patients. Changes in left ventricular dimensions and ejection fraction were similar for both groups. Univariate predictors of 2-year clinical outcome included baseline creatinine level, diuretic usage, and anemia; in multivariable regression, baseline anemia was an independent predictor for outcome (hazard ratio [HR] 1.79, 95% confidence interval [CI] [1.22-2.63], p = 0.003). The quartile with the most negative change in Hb concentration over time (≤-1.00 g/dL) had poorer event-free 2-year survival (HR 1.84, CI [1.13-3.00], p = 0.014).
  
  
  CONCLUSIONS
  Baseline anemia and early postimplantation decline in Hb levels are associated with a worse 2-year prognosis in CRT patients, even though the magnitude of left ventricular reverse remodeling is similar compared to non-anemic patients.
authors.affiliation: Harvard Medical School, Boston, MA, USA.
authors.forename: Ramkumar V
authors.initials: RV
authors.lastname: Venkateswaran
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Freeman
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Neal
authors.initials: N
authors.lastname: Chatterjee
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Jagdesh
authors.initials: J
authors.lastname: Kandala
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Orencole
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Eszter M
authors.initials: EM
authors.lastname: Vegh
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Parks
authors.affiliation: University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Cowburn
authors.affiliation: Harvard Medical School, Boston, MA, USA.|Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: G William
authors.initials: GW
authors.lastname: Dec
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA.
authors.forename: Jagmeet P
authors.initials: JP
authors.lastname: Singh
authors.affiliation: Massachusetts General Hospital, Cardiology Division, Boston, MA, USA. rasmus.borgquist@med.lu.se.|Lund University, Arrhythmia Clinic, Skane University Hospital, Lund, Sweden. rasmus.borgquist@med.lu.se.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Borgquist
mesh_terms: D000368:Aged; D000740:Anemia / Q000097:blood / Q000175:diagnosis* / Q000401:mortality*; D015415:Biomarkers / Q000097:blood; D001900:Boston / Q000453:epidemiology; D058406:Cardiac Resynchronization Therapy / Q000401:mortality*; D015897:Comorbidity; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000401:mortality* / Q000517:prevention & control*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D015994:Incidence; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D006454:Hemoglobins
keywords: Anemia; Cardiac resynchronization therapy; Heart failure; Prognostic factors; Risk stratification