title: Renal Response in Patients with Chronic Kidney Disease Predicts Outcome Following Cardiac Resynchronization Therapy.
abstract: BACKGROUND
  Chronic kidney disease (CKD) severity is associated with increased morbidity and mortality in congestive heart failure. There is a paucity of data regarding renal improvement after cardiac resynchronization therapy (CRT) and its potential impact on clinical outcomes, especially in patients with severe CKD.
  
  
  METHODS
  This was a retrospective analysis of a prospectively collected cohort of 260 patients with CKD undergoing CRT at a single center. Renal function was compared before and after CRT. The primary end point was a composite of death, heart transplant, and left ventricular assist device (LVAD), assessed at 5 years.
  
  
  RESULTS
  Patients with more severe CKD demonstrated increased risk of death, transplant, or LVAD following CRT (P = 0.015). Renal response (estimated glomerular filtration rate improvement ≥10 mL/min/1.73 m(2) ) was observed in 14% of all patients and 28% of patients with stage IV CKD. Independent predictors of renal response included left ventricular ejection fraction improvement (odds ratio [OR] 1.06, confidence interval [CI] 1.01-1.10), angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use (OR 4.31, CI 1.08-17.23), and advanced CKD stage (OR 2.19, CI 1.14-4.23). Renal response independently decreased hazard of the primary outcome (HR 0.24, CI 0.08-0.73, P = 0.01). Renal responders with stage IV CKD had 80% 5-year event-free survival, compared to 0% for nonrenal responders in stage IV (P = 0.03).
  
  
  CONCLUSIONS
  Although severity of CKD is associated with poorer outcome after CRT, improvement in renal function can occur in patients across all CKD stages. Renal responders, including those with stage IV CKD, demonstrate favorable 5-year outcomes. Assessment of renal response may help better prognostic outcomes following CRT.
authors.affiliation: Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Singal
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Gaurav A
authors.initials: GA
authors.lastname: Upadhyay
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Lund University, Arrhythmia Clinic, Skane University Hospital, Lund, Sweden.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Borgquist
authors.affiliation: Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Friedman
authors.affiliation: Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Neal A
authors.initials: NA
authors.lastname: Chatterjee
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Jagdesh
authors.initials: J
authors.lastname: Kandala
authors.affiliation: Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Mi Young
authors.initials: MY
authors.lastname: Park
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Mary
authors.initials: M
authors.lastname: Orencole
authors.affiliation: Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: George W
authors.initials: GW
authors.lastname: Dec
authors.affiliation: Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Picard
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Jagmeet P
authors.initials: JP
authors.lastname: Singh
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.|Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Theofanie
authors.initials: T
authors.lastname: Mela
mesh_terms: D000368:Aged; D001900:Boston / Q000453:epidemiology; D058406:Cardiac Resynchronization Therapy / Q000401:mortality*; D059347:Cardio-Renal Syndrome / Q000175:diagnosis / Q000401:mortality; D015897:Comorbidity; D005260:Female; D060730:Glomerular Filtration Barrier; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis* / Q000401:mortality*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015996:Survival Rate; D016896:Treatment Outcome
keywords: cardiac resynchronization therapy; cardiorenal syndrome; chronic kidney disease; heart failure; pacemakers