title: Regadenoson pharmacologic rubidium-82 PET: a comparison of quantitative perfusion and function to dipyridamole.
abstract: BACKGROUND
  Dipyridamole is used for stress (82)rubidium chloride ((82)RbCl) PET because of its long hyperemic duration. Regadenoson has advantages of a fixed dose and favorable symptom profile, but its mean maximal hyperemia is only 2.3 minutes. To determine its suitability for (82)RbCl PET, we imaged subjects using a regadenoson protocol based on its hyperemic response and compared the images in the same subjects having dipyridamole PET.
  
  
  METHODS
  In 32 subjects (23 M), we assessed visually by blinded interpretation and quantitatively compared summed stress and difference scores, total perfusion deficit (TPD), LVEF, LV volumes, and change in stress-rest function. Linear correlation and Bland-Altman analysis of the paired measurements were applied for evaluation of differences. Paired t test and Pearson's correlation were applied for testing of significance.
  
  
  RESULTS
  The images were interpreted the same by visual assessment. Twenty-six (26) subjects had reversible defects; by quantitation the SSS was 12.9 ± 7.0 and 14.1 ± 6.4 (P = .23) and SDS was 7.0 ± 6.8 versus 7.6 ± 6.2 (P = .40) for dipyridamole and regadenoson, respectively. Six (6) subjects had <5% likelihood of CAD and were normal by both. All paired measurements showed a high positive correlation between regadenoson and dipyridamole; stress segmental perfusion Reg = 0.93Dip + 4.4, r = 0.88; TPD Reg = 0.94Dip + 0.41, r = 0.93; LVEF Reg = 0.92Dip + 4.7, r = 0.95; stress minus rest LVEF Reg = 0.87Dip - 0.99, r = 0.82.
  
  
  CONCLUSIONS
  Regadenoson stress (82)RbCl PET perfusion defect and cardiac function measurements are visually and quantitatively equivalent to dipyridamole studies and can be obtained with the clinical advantages of regadenoson.
authors.affiliation: Cardiovascular Imaging Technologies, LLC, 4320 Wornall Road, Suite 55, Kansas City, MO 64111, USA. medigent@kc.rr.com
authors.forename: S James
authors.initials: SJ
authors.lastname: Cullom
authors.forename: James A
authors.initials: JA
authors.lastname: Case
authors.forename: Staci A
authors.initials: SA
authors.lastname: Courter
authors.forename: A Iain
authors.initials: AI
authors.lastname: McGhie
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Bateman
mesh_terms: D000368:Aged; D001794:Blood Pressure; D015992:Body Mass Index; D002712:Chlorides / Q000494:pharmacology; D004176:Dipyridamole; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods; D010477:Perfusion; D049268:Positron-Emission Tomography / Q000379:methods*; D011687:Purines; D011720:Pyrazoles; D019275:Radiopharmaceuticals; D012413:Rubidium / Q000494:pharmacology; D012414:Rubidium Radioisotopes; D016277:Ventricular Function, Left
chemical_list: D002712:Chlorides; D011687:Purines; D011720:Pyrazoles; D019275:Radiopharmaceuticals; D012414:Rubidium Radioisotopes; C430916:regadenoson; D004176:Dipyridamole; D012413:Rubidium; C032710:rubidium chloride