title: The effect of obesity on regadenoson-induced myocardial hyperemia: a quantitative magnetic resonance imaging study.
abstract: The A2(A) receptor agonist, regadenoson, is increasingly used as a vasodilator during nuclear myocardial perfusion imaging. Regadenoson is administered as a single, fixed dose. Given the frequency of obesity in patients with symptoms of heart disease, it is important to know whether the fixed dose of regadenoson produces maximal coronary hyperemia in subjects of widely varying body size. Thirty subjects (12 female, 18 male, mean BMI 30.3 ± 6.5, range 19.6-46.6) were imaged on a 3T magnetic resonance scanner. Imaging with a saturation recovery radial turboFLASH sequence was done first at rest, then during adenosine infusion (140 μg/kg/min) and 30 min later with regadenoson (0.4 mg/5 ml bolus). A 5 cc/s injection of Gd-BOPTA was used for each perfusion sequence, with doses of 0.02, 0.03 and 0.03 mmol/kg, respectively. Analysis of the upslope of myocardial time-intensity curves and quantitative processing to obtain myocardial perfusion reserve (MPR) values were performed for each vasodilator. The tissue upslopes for adenosine and regadenoson matched closely (y = 1.1x + 0.03, r = 0.9). Mean MPR was 2.3 ± 0.6 for adenosine and 2.4 ± 0.9 for regadenoson (p = 0.14). There was good agreement between MPR measured with adenosine and regadenoson (y = 1.1x - 0.06, r = 0.7). The MPR values measured with both agents tended to be lower as BMI increased. There were no complications during administration of either agent. Regadenoson produced fewer side effects. Fixed dose regadenoson and weight adjusted adenosine produce similar measures of MPR in patients with a wide range of body sizes. Regadenoson is a potentially useful vasodilator for stress MRI studies.
authors.affiliation: UCAIR, Department of Radiology, University of Utah, Salt Lake City, UT, USA.
authors.forename: Edward V R
authors.initials: EV
authors.lastname: DiBella
authors.forename: Jacob U
authors.initials: JU
authors.lastname: Fluckiger
authors.forename: Liyong
authors.initials: L
authors.lastname: Chen
authors.forename: Tae Ho
authors.initials: TH
authors.lastname: Kim
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Pack
authors.forename: Brian
authors.initials: B
authors.lastname: Matthews
authors.forename: Ganesh
authors.initials: G
authors.lastname: Adluru
authors.forename: Tiffany
authors.initials: T
authors.lastname: Priester
authors.forename: Suman
authors.initials: S
authors.lastname: Kuppahally
authors.forename: Ronny
authors.initials: R
authors.lastname: Jiji
authors.forename: Chris
authors.initials: C
authors.lastname: McGann
authors.forename: Sheldon E
authors.initials: SE
authors.lastname: Litwin
mesh_terms: D000241:Adenosine / Q000008:administration & dosage* / Q000009:adverse effects; D058917:Adenosine A2 Receptor Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D000328:Adult; D015992:Body Mass Index; D003287:Contrast Media; D003326:Coronary Circulation / Q000187:drug effects*; D054796:Drug Dosage Calculations; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology*; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009765:Obesity / Q000175:diagnosis / Q000503:physiopathology*; D009942:Organometallic Compounds; D011237:Predictive Value of Tests; D011687:Purines / Q000008:administration & dosage* / Q000009:adverse effects; D011720:Pyrazoles / Q000008:administration & dosage* / Q000009:adverse effects; D013997:Time Factors; D014589:Utah; D014665:Vasodilator Agents / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D058917:Adenosine A2 Receptor Antagonists; D003287:Contrast Media; D009942:Organometallic Compounds; D011687:Purines; D011720:Pyrazoles; D014665:Vasodilator Agents; C064572:gadobenic acid; C430916:regadenoson; D008536:Meglumine; D000241:Adenosine