title: The impact of regimented aminophylline use on extracardiac radioisotope activity in patients undergoing regadenoson stress SPECT myocardial perfusion imaging: a substudy of the ASSUAGE trial.
abstract: BACKGROUND
  In patients undergoing regadenoson stress SPECT myocardial perfusion imaging (MPI), the impact of the regimented administration of aminophylline on the cardiac-to-extracardiac photon activity ratio is unknown.
  
  
  METHODS
  This is a substudy of the ASSUAGE trial (NCT01250496); a double-blinded, randomized, placebo-controlled clinical trial which investigated the attenuation of regadenoson-related adverse effects using 75 mg of intravenous aminophylline vs placebo, administered 90 seconds following (99m)Tc-tetrofosmin injection in patients undergoing regadenoson stress SPECT-MPI. In subjects with normal MPI enrolled in the trial, we sampled from the antero-posterior planar projection of the post-stress scintigraphic data the mean photon activity in the myocardium, liver, bowel, and lungs. The mean cardiac-to-extracardiac activity ratios were compared between patients randomized to aminophylline vs placebo.
  
  
  RESULTS
  We studied 158 eligible subjects, randomized to receive aminophylline (n = 86) or placebo (n = 72). The means of photon activity ratios of the heart-to-liver, heart-to-bowel, heart-to-lungs, inferior wall of the heart-to-liver, and inferior wall of the heart-to-bowel were not statistically different between those who received aminophylline vs placebo (P values > .30). Only the time lapse between stress (99m)Tc-tetrofosmin injection and stress SPECT acquisition independently correlated with higher heart-to-liver and heart-to-bowel activity ratios (P values ≤ .01). Patients' body mass index independently correlated with lower heart-to-lung ratio (P = .009).
  
  
  CONCLUSIONS
  The regimented intravenous aminophylline use following regadenoson stress does not significantly improve the cardiac-to-extracardiac photon activity ratio in patients undergoing regadenoson stress (99m)Tc-tetrofosmin SPECT-MPI.
authors: Division of Adult Cardiology, John H. Stroger, Jr. Hospital of Cook County, Chicago, IL, USA.
authors: Wassim
authors: W
authors: Ballany
authors: Khaled
authors: K
authors: Mansour
authors: Raysa
authors: R
authors: Morales Demori
authors: Mohammed
authors: M
authors: Al-Amoodi
authors: Rami
authors: R
authors: Doukky
mesh_terms: D058908:Adenosine A2 Receptor Agonists / Q000009:adverse effects; D000628:Aminophylline / Q000008:administration & dosage*; D002316:Cardiotonic Agents / Q000008:administration & dosage; D004311:Double-Blind Method; D005080:Exercise Test / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000139:chemically induced* / Q000517:prevention & control*; D007089:Image Enhancement / Q000379:methods; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000009:adverse effects / Q000379:methods*; D015990:Placebo Effect; D011687:Purines / Q000009:adverse effects*; D011720:Pyrazoles / Q000009:adverse effects*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000009:adverse effects / Q000379:methods*; D014665:Vasodilator Agents / Q000009:adverse effects
chemical_list: D058908:Adenosine A2 Receptor Agonists; D002316:Cardiotonic Agents; D011687:Purines; D011720:Pyrazoles; D014665:Vasodilator Agents; D000628:Aminophylline; C430916:regadenoson