title: Effectiveness of cardiac resynchronization therapy in diabetic patients with ischemic and nonischemic cardiomyopathy.
abstract: BACKGROUND
  Diabetes mellitus (DM) increases the risk for the development of both ischemic and nonischemic cardiomyopathy. We aimed to identify differences in response to cardiac resynchronization therapy with a defibrillator (CRT-D) among DM patients with ischemic or nonischemic cardiomyopathy.
  
  
  METHODS
  Cox proportional hazards regression modeling was used to assess clinical response to CRT-D (defined as CRT-D vs. defibrillator-only reduction in the risk of heart failure [HF] or death) and echocardiographic response (defined as percent reduction in left ventricular end diastolic and systolic volume [LVEDV and LVESV, respectively] at 12 month of follow-up compared with baseline values) among 552 diabetic patients with ischemic (n = 367) or nonischemic (n = 185) cardiomyopathy enrolled in MADIT-CRT.
  
  
  RESULTS
  The clinical benefit of CRT-D was more pronounced among nonischemic patients (HR = 0.30 [P < 0.001] than among ischemic patients (HR = 0.59 [P = 0.004]; P for interaction = 0.10). Nonischemic patients also experienced significantly greater reductions in LVESV and LVEDV at 12 months with CRT-D compared with ischemic patients (P < 0.001 for both). Subgroup analysis showed that the most pronounced reduction in HF or death with CRT-D therapy occurred in nonischemic patients who were women (83% risk-reduction [P < 0.001]), had a lower BMI (<30/kg/m(2) : 79% risk-reduction [P < 0.001]), or had left bundle branch block at enrollment (82% risk-reduction [P < 0.001]).
  
  
  CONCLUSIONS
  The present study shows that treatment with CRT-D in at-risk cardiac patients with DM is associated with substantial reductions in the risk of HF or death and improvement in cardiac remodeling in those with ischemic and nonischemic cardiomyopathy, with a more pronounced benefit in patients with nonischemic disease.
authors.affiliation: Cardiology Unit of the Department of Medicine, University of Rochester Medical Center, Rochester, NY, USA.
authors.forename: Jenie
authors.initials: J
authors.lastname: George
authors.forename: Alon
authors.initials: A
authors.lastname: Barsheshet
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moss
authors.forename: David
authors.initials: D
authors.lastname: Martin
authors.forename: Gregory
authors.initials: G
authors.lastname: Ouellet
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Ilan
authors.initials: I
authors.lastname: Goldenberg
mesh_terms: D000328:Adult; D058406:Cardiac Resynchronization Therapy; D009202:Cardiomyopathies / Q000503:physiopathology / Q000628:therapy*; D017147:Defibrillators, Implantable; D003925:Diabetic Angiopathies / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006333:Heart Failure / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000503:physiopathology / Q000628:therapy; D016016:Proportional Hazards Models; D020257:Ventricular Remodeling; D055815:Young Adult