title: Comparison of 3- versus 6-minute infusions of adenosine in thallium-201 myocardial perfusion imaging.
abstract: Adenosine thallium stress testing has a demonstrated utility in the detection of coronary artery disease. The optimal dose for diagnostic efficacy with minimal side effects has not been critically evaluated. A randomized 3- and 6-minute infusion of adenosine (140 micrograms/kg/min) was performed in 11 subjects. Subjects reported more side effects during the 6-minute infusion protocol (p < 0.05). Hemodynamic changes were not different during either infusion duration. All dysrhythmias began within 2 minutes and therefore the duration of the infusion did not influence their occurrence. Segmental comparison of the stress images demonstrated an 89% agreement. Delayed scans demonstrated a 79% agreement. There was a higher incidence of redistribution following the 6-minute infusion (p = 0.014). We conclude that when side effects necessitate the discontinuation of a 6-minute adenosine infusion, a diagnostic test can still be achieved if 2 to 3 minutes of adenosine have been administered before the thallium injection; however, the amount of viable myocardium may be underestimated.
authors.affiliation: Myocardial Isotope Research Laboratory, University of Massachusetts Medical Center, Worcester 01655.
authors.forename: B J
authors.initials: BJ
authors.lastname: Villegas
authors.forename: R C
authors.initials: RC
authors.lastname: Hendel
authors.forename: S T
authors.initials: ST
authors.lastname: Dahlberg
authors.forename: B A
authors.initials: BA
authors.lastname: McSherry
authors.forename: J A
authors.initials: JA
authors.lastname: Leppo
mesh_terms: D000241:Adenosine / Q000008:administration & dosage*; D000368:Aged; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004334:Drug Administration Schedule; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes
chemical_list: D013794:Thallium Radioisotopes; D000241:Adenosine