title: Long-Term Outcomes With Cardiac Resynchronization Therapy in Patients With Mild Heart Failure With Moderate Renal Dysfunction.
abstract: BACKGROUND
  We aimed to determine the impact of renal function on long-term outcomes with cardiac resynchronization therapy with defibrillator among patients with mild heart failure (HF).
  
  
  RESULTS
  We stratified 1820 Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy patients by QRS morphology into those with and without left bundle-branch block. Subgroups within each QRS morphology category were created based on glomerular filtration rate (GFR): GFR <60 and ≥60 mL/min per 1.73 m(2). Primary end point was death; secondary end points were HF/death and HF events alone during long-term follow-up. Among 1274 left bundle-branch block patients, 413 (32%) presented with GFR <60 (mean, 48.1±8.3) mL/min per 1.73 m(2). Relative to the 861 (68%) patients with GFR ≥60 (mean, 79.6±16.0) mL/min per 1.73 m(2), low-GFR patients experienced higher risk of death (hazard ratio [HR], 2.09; 95% confidence interval [CI], 1.53-2.86; P<0.01) and HF/death (HR, 1.46; 95% CI, 1.17-1.82; P<0.01). In both GFR groups, cardiac resynchronization therapy with defibrillator was associated with reduction in death (GFR <60: HR, 0.66; 95% CI, 0.44-1.00; P=0.05 and GFR ≥60: HR, 0.68; 95% CI, 0.44-1.05; P=0.08) and HF/death (GFR <60: HR, 0.49; 95% CI, 0.36-0.67; P<0.01 and GFR ≥60: HR, 0.50; 95% CI, 0.38-0.66; P<0.01). In the low-GFR group, there was greater absolute reduction in risk of death (GFR <60: 14% and GFR ≥60: 6%) and HF/death (GFR <60: 25 and GFR ≥60: 15%). Among non-left bundle-branch block patients, low GFR predicted outcomes; however, no benefit from cardiac resynchronization therapy with defibrillator was observed.
  
  
  CONCLUSIONS
  In patients with mild HF, moderate renal dysfunction is associated with higher risk of death and HF during long-term follow-up. Patients with left bundle-branch block, regardless of baseline renal function, derive long-term benefit from cardiac resynchronization therapy with defibrillator, with greater absolute risk reduction in death and HF among those with moderate renal dysfunction.
  
  
  BACKGROUND
  URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00180271, NCT01294449, and NCT02060110.
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Usama A
authors.initials: UA
authors.lastname: Daimee
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moss
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Yitschak
authors.initials: Y
authors.lastname: Biton
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Scott D
authors.initials: SD
authors.lastname: Solomon
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Helmut U
authors.initials: HU
authors.lastname: Klein
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Bronislava
authors.initials: B
authors.lastname: Polonsky
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zareba
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.).
authors.forename: Ilan
authors.initials: I
authors.lastname: Goldenberg
authors.affiliation: From the Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, NY (U.A.D., A.J.M., Y.B., H.U.K., S.M., B.P., W.Z., I.G., V.K.); and Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.D.S.). Valentina.Kutyifa@heart.rochester.edu.
authors.forename: Valentina
authors.initials: V
authors.lastname: Kutyifa
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000401:mortality; D058409:Cardiac Resynchronization Therapy Devices; D015897:Comorbidity; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D005260:Female; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology*; D007674:Kidney Diseases / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
keywords: bundle-branch block; cardiac resynchronization therapy; defibrillators, implantable; heart failure; mortality; renal insufficiency