title: Rapid detection of coronary artery stenoses with real-time perfusion echocardiography during regadenoson stress.
abstract: BACKGROUND
  Real-time myocardial contrast echocardiography permits the detection of myocardial perfusion abnormalities during stress echocardiography, which may improve the accuracy of the test in detecting coronary artery stenoses. We hypothesized that this technique could be used after a bolus injection of the selective A2A receptor agonist regadenoson to rapidly and safely detect coronary artery stenoses.
  
  
  RESULTS
  In 100 patients referred for quantitative coronary angiography, real-time myocardial contrast echocardiography was performed during a continuous intravenous infusion of 3% Definity at baseline and at 2-minute intervals for up to 6 minutes after a regadenoson bolus injection (400 μg). Myocardial perfusion was assessed by examination of myocardial contrast replenishment after brief high mechanical index impulses. A perfusion defect was defined as a delay (>2 seconds) in myocardial contrast replenishment in 2 contiguous segments. Wall motion was also analyzed. The overall sensitivity/specificity/accuracy for myocardial perfusion analysis in detecting a >50% diameter stenosis was 80%/74%/78%, whereas for wall motion analysis it was 60%/72%/66% (P<0.001 for differences in sensitivity). Sensitivity for myocardial perfusion analysis was highest on images obtained during the first 2 minutes after regadenoson bolus (P<0.001 compared with wall motion), whereas wall motion sensitivity was highest at the 4-to-6-minute period after the bolus. No significant side effects occurred after regadenoson bolus injection.
  
  
  CONCLUSIONS
  Regadenoson real-time myocardial contrast echocardiography appears to be a feasible, safe, and rapid noninvasive method for the detection of significant coronary artery stenoses.
authors.affiliation: University of Nebraska Medical Center, Omaha, NE 68198-8865, USA. trporter@unmc.edu
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Porter
authors.forename: Mary
authors.initials: M
authors.lastname: Adolphson
authors.forename: Robin R
authors.initials: RR
authors.lastname: High
authors.forename: Lynette M
authors.initials: LM
authors.lastname: Smith
authors.forename: Joan
authors.initials: J
authors.lastname: Olson
authors.forename: Michelle
authors.initials: M
authors.lastname: Erdkamp
authors.forename: Feng
authors.initials: F
authors.lastname: Xie
authors.forename: Edward
authors.initials: E
authors.lastname: O'Leary
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Wong
authors.forename: Susan
authors.initials: S
authors.lastname: Eifert-Rain
authors.forename: Mary E
authors.initials: ME
authors.lastname: Hagen
authors.forename: Sahar S
authors.initials: SS
authors.lastname: Abdelmoneim
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Mulvagh
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010477:Perfusion / Q000379:methods*; D011687:Purines; D011720:Pyrazoles; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D003287:Contrast Media; D011687:Purines; D011720:Pyrazoles; C430916:regadenoson