title: Improved outcome with preventive cardiac resynchronization therapy in the elderly: a MADIT-CRT substudy.
abstract: BACKGROUND
  Elderly patients comprise a large portion of patients with heart failure (HF). Limited data exist on the effectiveness of cardiac resynchronization therapy with defibrillator (CRT-D) in patients with mild HF symptoms in this population.
  
  
  RESULTS
  The benefit of CRT-D compared with ICD-only therapy in reducing HF or death was assessed by age categories (prespecified as <60 [n = 548], 60-74 [n = 941], and ≥75 [n = 331] years) among 1,820 patients in MADIT-CRT. In patients with ICD-only, there was a graded age-related increase in the Kaplan-Meier cumulative probability of HF or death at 3-year follow-up (19%, 33%, and 36%, in patients aged <60, 60-74, and ≥75 years, respectively, P = 0.003). Multivariate analysis demonstrated that CRT-D therapy was associated with a significant reduction in the risks of HF or death in patients aged 60-74, and ≥75 years (HR = 0.57, P = <0.001 and HR = 0.59, P = 0.017, respectively), and no significant benefit in patients aged <60 years (HR = 0.81, P = 0.3; P-value for all treatment-by-age interactions >0.10). There was no significant difference in the rate of device-related adverse events within 90 days following CRT-D implantation among age-subgroups (16.7%, 15.7%, and 11.7%, in patients <60, 60-74, and ≥75 years, respectively, P = 0.42).
  
  
  CONCLUSIONS
  CRT-D was associated with a significant clinical benefit in older patients (≥60 years) during an average 2.4-year follow-up. These effects were preserved for the elderly patients ≥75 years of age but attenuated in patients <60 years. Elderly patients had no increase in device-related adverse events compared with younger patients.
authors.affiliation: Department of Internal Medicine, University of Rochester Medical Center, Rochester, New York 14642, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Penn
authors.forename: Ilan
authors.initials: I
authors.lastname: Goldenberg
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moss
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zareba
authors.forename: Helmut U
authors.initials: HU
authors.lastname: Klein
authors.forename: David S
authors.initials: DS
authors.lastname: Cannom
authors.forename: Scott D
authors.initials: SD
authors.lastname: Solomon
authors.forename: Alon
authors.initials: A
authors.lastname: Barsheshet
authors.forename: David T
authors.initials: DT
authors.lastname: Huang
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D058406:Cardiac Resynchronization Therapy / Q000639:trends*; D009202:Cardiomyopathies / Q000503:physiopathology* / Q000517:prevention & control* / Q000628:therapy; D004554:Electric Countershock / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D055502:Secondary Prevention; D016896:Treatment Outcome