Comparison of myocardial washout rate of thallium-201 between rest, dipyridamole with and without aminophylline, and exercise states in normal subjects.
The myocardial washout rate of thallium-201 was studied in 85 subjects with a less than 5% likelihood of coronary artery disease undergoing rest (group I, n = 12), dipyridamole (group II, n = 24) and exercise (group III, n = 49) stress thallium-201 scintigraphy. Subjects receiving dipyridamole were subdivided into group IIA (n = 11), who received an aminophylline injection 10 minutes after dipyridamole infusion, and group IIB (n = 13), who did not. The mean and highest washout rate values in each of 3 segments in the anterior, 45 degrees and 85 degrees left anterior oblique views were calculated. In group II the mean washout rate of thallium-201 was similar in all segments of each view and the overall mean washout rate did not differ between the 3 views studied. There was a good correlation between the mean and highest washout rate values in individual subjects (r = 0.98, p less than 0.001). The mean +/- standard deviation myocardial 4-hour washout rate of thallium-201 (anterior view) was 10 +/- 6% in group I compared with 40 +/- 14% in group IIA (p less than 0.05 vs group I), 31 +/- 13% in group IIB (p less than 0.05 vs group I) and 54 +/- 11% in group III (p less than 0.05 each vs group IIA and group IIB, respectively). There was a wide variation in mean washout rate values in group II (range 12 to 58%), and this variation was not altered by aminophylline administration.(ABSTRACT TRUNCATED AT 250 WORDS)
O'Byrne
G T
GT
Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California 90048.
Rodrigues
E A
EA
Maddahi
J
J
Van Train
K F
KF
Wong
C
C
Resser
K
K
Friedman
J D
JD
Berman
D S
DS
D000328:Adult; D000628:Aminophylline / Q000008:administration & dosage*; D004176:Dipyridamole; D015444:Exercise; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012016:Reference Values; D013794:Thallium Radioisotopes
D013794:Thallium Radioisotopes; D000628:Aminophylline; D004176:Dipyridamole