title: Pooled comparison of regadenoson versus adenosine for measuring fractional flow reserve and coronary flow in the catheterization laboratory.
abstract: BACKGROUND
  Adenosine is the gold standard for augmenting coronary flow during fractional flow reserve (FFR) testing of intermediate coronary stenoses. However, intravenous infusion is time-consuming and intracoronary injection is subject to variability. Regadenoson is a newer adenosine alternative administered as a single intravenous bolus during nuclear stress testing, but its efficacy and safety during FFR testing have been evaluated only in small, single-center studies.
  
  
  METHODS
  We pooled data from 5 academic hospitals, in which patients undergoing clinically-indicated FFR prospectively underwent comparison of intravenous adenosine infusion (140-175mcg/kg/min) versus regadenoson bolus (400mcg). Hemodynamics and symptoms with adenosine were recorded until maximal hyperemia occurred, and after returning to baseline hemodynamics, regadenoson was administered and monitoring was repeated. In a subset of patients with coronary flow data, average peak velocity (APV) at the distal flow sensor was recorded.
  
  
  RESULTS
  Of 149 patients enrolled, mean age was 59±9years, 76% were male, and 54% underwent testing of the left anterior descending artery. Mean adenosine-FFR and regadenoson-FFR were identical (0.82±0.10) with excellent correlation of individual values (r=0.96, p<0.001) and no difference in patient-reported symptoms. Four patients (2.6%) had discrepancies between the 2 drugs for the clinical decision-making cutoff of FFR≤0.80. Coronary flow responses to adenosine and regadenoson were similar (APV at maximal hyperemia 36cm/s for both, p=0.81).
  
  
  CONCLUSIONS
  Regadenoson single-bolus administration has comparable FFR, symptoms, and coronary flow augmentation when compared with standard intravenous adenosine infusion. With its greater ease of administration, regadenoson may be a more "user-friendly" option for invasive ischemic testing.
authors.affiliation: Mercy Heart and Vascular, 901 Patients First Drive, Washington, MO 63090, USA; Saint Louis University, 3635 Vista Ave, St. Louis, MO 63110, USA. Electronic address: jstolker@yahoo.com.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Stolker
authors.affiliation: Saint Louis University, 3635 Vista Ave, St. Louis, MO 63110, USA. Electronic address: limmj@slu.edu.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lim
authors.affiliation: University of Southern California, 1510 San Pablo St, Suite 322, Los Angeles, CA 90033, USA. Electronic address: david.shavelle@med.usc.edu.
authors.forename: David M
authors.initials: DM
authors.lastname: Shavelle
authors.affiliation: Albert Einstein Medical Center, 5501 Old York Rd, Philadelphia, PA 19141, USA. Electronic address: morrisdl@einstein.edu.
authors.forename: D Lynn
authors.initials: DL
authors.lastname: Morris
authors.affiliation: University of Florida Health-Jacksonville, 655 West 8th St, Jacksonville, FL 32209, USA. Electronic address: dominick.angiolillo@jax.ufl.edu.
authors.forename: Dominick J
authors.initials: DJ
authors.lastname: Angiolillo
authors.affiliation: University of Florida Health-Jacksonville, 655 West 8th St, Jacksonville, FL 32209, USA. Electronic address: luis.guzman@jax.ufl.edu.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Guzman
authors.affiliation: Saint Luke's Mid America Heart Institute, 4401 Wornall Road, Kansas City, MO 64111, USA. Electronic address: kfkennedy@saint-lukes.org.
authors.forename: Kevin F
authors.initials: KF
authors.lastname: Kennedy
authors.affiliation: Saint Louis University, 3635 Vista Ave, St. Louis, MO 63110, USA. Electronic address: eweber1@slu.edu.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Weber
authors.affiliation: University of Southern California, 1510 San Pablo St, Suite 322, Los Angeles, CA 90033, USA. Electronic address: meena.zareh@med.usc.edu.
authors.forename: Meena
authors.initials: M
authors.lastname: Zareh
authors.affiliation: Mercy Heart and Vascular, 901 Patients First Drive, Washington, MO 63090, USA; Saint Louis University, 3635 Vista Ave, St. Louis, MO 63110, USA. Electronic address: robneumayr@gmail.com.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Neumayr
authors.affiliation: University of Florida Health-Jacksonville, 655 West 8th St, Jacksonville, FL 32209, USA. Electronic address: martin.zenni@jax.ufl.edu.
authors.forename: Martin M
authors.initials: MM
authors.lastname: Zenni
mesh_terms: D000241:Adenosine / Q000008:administration & dosage / Q000627:therapeutic use*; D000368:Aged; D002404:Catheterization / Q000379:methods; D003326:Coronary Circulation / Q000187:drug effects*; D023921:Coronary Stenosis / Q000175:diagnosis; D003331:Coronary Vessels / Q000187:drug effects; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000187:drug effects*; D006801:Humans; D006940:Hyperemia / Q000188:drug therapy; D007262:Infusions, Intravenous / Q000379:methods; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011687:Purines / Q000008:administration & dosage / Q000627:therapeutic use*; D011720:Pyrazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D011687:Purines; D011720:Pyrazoles; D014665:Vasodilator Agents; C430916:regadenoson; D000241:Adenosine
keywords: Adenosine; Fractional flow reserve; Myocardial ischemia; Regadenoson