Comparison of exercise, dipyridamole, adenosine, and dobutamine stress with the use of Tc-99m tetrofosmin tomographic imaging.
OBJECTIVE
The purpose of this study was to compare defect extent and severity and myocardial uptake with exercise and pharmacologic stress with technetium-99m (Tc-99m) tetrofosmin tomographic myocardial perfusion imaging.


BACKGROUND
Detection of stress-induced myocardial perfusion defects depends on both a disparity in blood flow between normal and stenotic vessels and the extraction fraction and linearity of myocardial uptake of the tracer. There are limited clinical data for exercise or pharmacologic stress with Tc-99m tetrofosmin tomographic myocardial perfusion imaging.


METHODS
Thirty-one patients with coronary artery disease and 7 with a < 5% likelihood of coronary artery disease underwent on separate days Tc-99m tetrofosmin single-photon emission computed tomographic imaging at rest and after exercise, dipyridamole, adenosine, and dobutamine stress. Images were interpreted by a blinded consensus of 3 experienced readers with a 17-segment model and 5-point scoring system.


RESULTS
Compared with exercise, the summed stress score was smaller with dipyridamole (P < .01), and the reversibility score was smaller with both dipyridamole (P < .01) and dobutamine (P < .05), whereas the number of abnormal and reversible segments was less with both dipyridamole (P < .01 and P < .001, respectively) and dobutamine (both P < .05). No significant differences were found in the summed stress or reversibility scores and the number of abnormal or reversible segments between exercise and adenosine.


CONCLUSIONS
Compared with exercise, defect extent, severity, and reversibility are less with dipyridamole and dobutamine with Tc-99m tetrofosmin single photon emission computed tomographic imaging.
Levine
M G
MG
Nuclear Cardiology Laboratory, Hartford Hospital, Conn. 06102-5037, USA.
Ahlberg
A W
AW
Mann
A
A
White
M P
MP
McGill
C C
CC
Mendes de Leon
C
C
Piriz
J M
JM
Waters
D
D
Heller
G V
GV
D000241:Adenosine; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D018592:Cross-Over Studies; D004176:Dipyridamole; D004280:Dobutamine; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000209:etiology; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D004280:Dobutamine; C078700:technetium tc-99m tetrofosmin; D004176:Dipyridamole; D000241:Adenosine