Adenosine technetium-99m-methoxy isobutyl isonitrile myocardial tomography in patients with coronary artery disease: comparison with exercise.
We compared the results of adenosine and bicycle exercise 99mTc-methoxy isobutyl isonitrile (MIBI) myocardial SPECT in 22 patients (18 males and 4 females, mean age 51 +/- 11 yr) with angiographically documented coronary artery disease (CAD).


METHODS
All patients were submitted on separate days to three intravenous injections of 99mTc-MIBI (20 mCi); one at rest, one during exercise and one during adenosine (140 micrograms/kg per min for 6 min with injection of 99mTc-MIBI at 4 min). A total of 484 myocardial segments were quantitatively analyzed.


RESULTS
Adenosine induced a significant increase of heart rate (94 +/- 16 bpm at peak versus 70 +/- 13 bpm at rest, p < 0.01). Systolic and diastolic blood pressure were not significantly different after adenosine infusion compared to rest. In all segments, a significant relationship between exercise and adenosine 99mTc-MIBI uptake was observed (r = 0.90, p < 0.0001). Concordance between the two studies for identification of perfusion status was observed in 438 (90%) of the 484 segments (kappa value of 0.81). Agreement on localization of the perfusion defect to a specific vascular territory was 92%.


CONCLUSIONS
Despite different hemodynamic effects, adenosine and exercise 99mTc-MIBI SPECT imaging provide similar information in the diagnosis and localization of CAD.
Department of Nuclear Medicine, University Federico II, Napoli, Italy.
A
A
Cuocolo
A
A
Soricelli
L
L
Pace
E
E
Nicolai
L
L
Castelli
A
A
Nappi
M
M
Imbriaco
C
C
Morisco
P J
PJ
Ell
M
M
Salvatore
D000241:Adenosine / Q000009:adverse effects; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003327:Coronary Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
D017256:Technetium Tc 99m Sestamibi; D000241:Adenosine