[Clinical value of rapid clearance in resting sestamibi cardiac SPECT in patients with acute myocardial infarction].
Resting 99mTc sestamibi (MIBI) SPECT and exercise-reinjection thallium-201 (T1) SPECT were performed in fourteen patients with acute myocardial infarction (AMI). MIBI SPECT were obtained 90 min (MIBI-90) and 300 min (MIBI-300) after injection of 370 MBq of MIBI at rest. MIBI-90 and MIBI-300 were compared with exercise T1 imaging (T1-EX) and T1 reinjection imaging (REINJ). Each SPECT image was divided into 22 segments and myocardial uptake was scored visually. Abnormal perfusion defects were observed in 94 myocardial regions. Worsening of the score was observed in 79 segments (84%) on MIBI-300 compared with MIBI-90. Total MIBI-300 uptake score per person was significantly greater than that at MIBI-90 (14.8 +/- 8.6 vs. 7.7 +/- 7.9, p = 0.001). The concordance rate of defect score between MIBI-90 and REINJ was significantly higher than that between MIBI-300 and REINJ (55% vs. 17%, p = 0.001). In nine patients without recanalization of an infarct-related artery, perfusion defects were seen in 74 segments. The concordance rate of defect scores between MIBI-300 and T1-EX was significantly higher than that between MIBI-90 and T1-EX (45% vs. 16%, p = 0.001). In conclusion, rapid clearance of MIBI was observed frequently in patients with AMI. MIBI-90 and MIBI-300 may reflect myocardial viability and areas at risk for AMI, respectively.
Itagane
H
H
Department of Cardiology, Osaka City General Hospital, Japan.
Yamagishi
H
H
Otsuka
M
M
Minami
S
S
Suto
Y
Y
Hato
K
K
Tojo
O
O
Okumachi
F
F
Haze
K
K
D003287:Contrast Media; D005080:Exercise Test; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
D003287:Contrast Media; D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi