Technetium-99m hexakis 2-methoxyisobutyl isonitrile: human biodistribution, dosimetry, safety, and preliminary comparison to thallium-201 for myocardial perfusion imaging.
The biodistribution, dosimetry, and safety of a new myocardial imaging agent, 99mTc-hexakis-2-methoxyisobutyl isonitrile (HEXAMIBI), was evaluated in 17 normal volunteers at rest and exercise (Phase I studies). Technetium-99m HEXAMIBI clears rapidly from the blood with good myocardial uptake and favorable myocardial-to-background ratios for myocardial imaging. Dosimetry allows for administration of up to 30 mCi (1, 110 Bq) of [99mTc]HEXAMIBI. The myocardial images were of good quality and appeared less granular with sharper myocardial walls compared to 201T1 images. The clinical efficacy of [99mTc]HEXAMIBI planar stress and rest imaging was evaluated in a multicenter Phase II clinical trial involving 38 patients. Of 36 patients with significant coronary artery disease, 35 patients (97%) had abnormal 201T1 stress images, and 32 (89%) had abnormal [99mTc]HEXAMIBI stress images (P = N.S.). Technetium-99m HEXAMIBI images correlated in 31/35 patients (86%) who had either scar or ischemia on 201T1 images. By segmental myocardial analysis, exact concordance was obtained in 463/570 myocardial segments (81%). This multicenter Phase I and II study indicates that planar [99mTc]HEXAMIBI stress imaging is safe and compares well with 201T1 stress imaging for detection of coronary artery disease.
Wackers
F J
FJ
Dept. of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06510.
Berman
D S
DS
Maddahi
J
J
Watson
D D
DD
Beller
G A
GA
Strauss
H W
HW
Boucher
C A
CA
Picard
M
M
Holman
B L
BL
Fridrich
R
R
D000328:Adult; D000368:Aged; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009942:Organometallic Compounds / Q000493:pharmacokinetics; D005082:Physical Exertion; D011829:Radiation Dosage; D011877:Radionuclide Imaging; D017256:Technetium Tc 99m Sestamibi; D013794:Thallium Radioisotopes; D014018:Tissue Distribution
D009942:Organometallic Compounds; D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi