title: Safety and feasibility of regadenoson use for suboptimal heart rate response during symptom-limited standard Bruce exercise stress test.
abstract: BACKGROUND
  Regadenoson during exercise stress test (ETT) can provide maximal hyperemia for myocardial perfusion imaging (MPI), along with exercise information. Our aim was to study the feasibility and safety of regadenoson injection at peak ETT for submaximal heart rate (HR) response.
  
  
  METHODS
  Consecutive patients who underwent SPECT MPI with standard Bruce ETT or supine-regadenoson (Supine-Reg) were analyzed. ETT patients were grouped as ETT-Max [maximal HR > 0.85 * (220 - age), N = 1,522], ETT-Submax (submaximal HR no regadenoson, N = 504), ETT-Reg (submaximal HR and regadenoson, N = 211).
  
  
  RESULTS
  The HR during ETT was submaximal in 715 (32%) patients. Of these, 211 patients (30%) underwent ETT-Reg (mean exercise duration: 5.5 ± 2.5 minutes). ETT-Reg patients had a higher frequency of hypertension, diabetes, smoking and beta-blocker use, similar rest systolic blood pressure (SBP), but lower rest and peak HR and peak SBP compared to ETT-Max patients. There were no serious complications with regadenoson. Side effects (49% vs 6%, P < .0001) were fewer and aminophylline use was lower with ETT-Reg compared to Supine-Reg (0.5% vs 8.1%, P = .001).
  
  
  CONCLUSIONS
  Submaximal HR response to ETT is common. ETT-Reg is safe, feasible, and well-tolerated. ETT-Reg facilitates a diagnostic MPI with reporting of functional capacity, exercise ECG/hemodynamic changes and MPI at maximal hyperemia.
authors.affiliation: Noninvasive Cardiovascular Imaging Program, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Sara L
authors.initials: SL
authors.lastname: Partington
authors.forename: Viswanatha
authors.initials: V
authors.lastname: Lanka
authors.forename: Jon
authors.initials: J
authors.lastname: Hainer
authors.forename: Ron
authors.initials: R
authors.lastname: Blankstein
authors.forename: Hicham
authors.initials: H
authors.lastname: Skali
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Forman
authors.forename: Marcelo F
authors.initials: MF
authors.lastname: Di Carli
authors.forename: Sharmila
authors.initials: S
authors.lastname: Dorbala
mesh_terms: D058908:Adenosine A2 Receptor Agonists / Q000009:adverse effects / Q000494:pharmacology*; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D005080:Exercise Test / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D011687:Purines / Q000009:adverse effects / Q000494:pharmacology*; D011720:Pyrazoles / Q000009:adverse effects / Q000494:pharmacology*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D058908:Adenosine A2 Receptor Agonists; D011687:Purines; D011720:Pyrazoles; C430916:regadenoson