title: Differences in heart rate response to adenosine and regadenoson in patients with and without diabetes mellitus.
abstract: BACKGROUND
  Adenosine and regadenoson increase heart rate (HR) when used as stress agents to produce coronary hyperemia due to direct sympathetic stimulation. We hypothesized that the HR response will be lower in patients with than in those without diabetes mellitus (DM).
  
  
  METHODS
  We studied the HR response (percentage maximal increase) in 2,000 patients in The ADenoscan Versus regAdenosoN Comparative Evaluation for Myocardial Perfusion Imaging (ADVANCE MPI 1 and 2) Trials with known DM status.
  
  
  RESULTS
  There were 643 patients with a history of DM (65.4 +/- 0.4 years, 32% women) and 1,357 patients with no DM (65.5 +/- 0.3 years, 29% women). Compared with non-DM, the DM group had higher HR at baseline (68.4 +/- 0.48 vs 65.2 +/- 0.31 beat/min, P < .001) and smaller HR response after adenosine or regadenoson administration (29.4% +/- 0.64% vs 36.1% +/- 0.54%, P < .001). Insulin therapy was associated with further blunting in the HR response (25.9% +/- 1.0% vs 31.2% +/- 0.8%, P < .001). After adjusting for beta-blocker intake, baseline HR, age, gender, renal function, systolic blood pressure, and left ventricular systolic function, DM independently accounted for a decrease in the HR response.
  
  
  CONCLUSIONS
  The HR response to adenosine and regadenoson in patients with DM is blunted. If additional studies confer an agreement between traditional tests for determination of autonomic neuropathy and this measure, then examination of HR response to these agents during myocardial perfusion imaging might add prognostic power.
authors.affiliation: Department of Medicine, University of Alabama at Birmingham, 35294-0006, USA. fadihage@uab.edu
authors.forename: Fadi G
authors.initials: FG
authors.lastname: Hage
authors.forename: Jaekyeong
authors.initials: J
authors.lastname: Heo
authors.forename: Billy
authors.initials: B
authors.lastname: Franks
authors.forename: Luiz
authors.initials: L
authors.lastname: Belardinelli
authors.forename: Brent
authors.initials: B
authors.lastname: Blackburn
authors.forename: Whedy
authors.initials: W
authors.lastname: Wang
authors.forename: Ami E
authors.initials: AE
authors.lastname: Iskandrian