Taillefer R, Lambert R, Bisson G, Benjamin C, Phaneuf D C
Department of Nuclear Medicine, Hotel-Dieu de Montreal, Canada.
J Nucl Cardiol. 1994 Sep-Oct;1(5 Pt 1):441-8. doi: 10.1007/BF02961598.
Previous studies have demonstrated that there is a "partial" myocardial redistribution of 99mTc-labeled sestamibi (MIBI) between 1 and 3 hours after intravenous injection at stress. The purpose of this prospective study was to compare MIBI single-photon emission computed tomographic (SPECT) imaging performed 15 and 60 minutes after the injection at stress in the detection of coronary artery disease.
Thirty-five patients with coronary artery disease (26 underwent coronary angiography and 23 had a positive 201Tl study result) were included in this study. SPECT imaging started 15 minutes after the injection of 25 to 30 mCi MIBI at peak stress (180-degree arc, 32 angles, 25 sec/view, and high-resolution collimator). Patients underwent reimaging at 60 minutes according to the same protocol and with the same gamma camera. A rest study was obtained 75 minutes after the injection of MIBI (25 to 30 mCi) at rest, 48 hours later. Images (divided for a total of 19 segments per patient) were interpreted by two blinded observers for patient diagnosis and segmental comparison. The patient diagnosis was the same for the two protocols: normal = 3, ischemia = 27, and scar = 5. The segmental agreement (kappa = 0.90) was 632/665 (95.0%). The imaging performed at 15 minutes detected normal, ischemia, and scar in 413, 189, and 63 segments, respectively, whereas the imaging performed at 60 minutes detected 422, 180, and 63 segments, respectively (difference not significant). The early and delayed images were placed side by side for subjective comparison of the extent of the defect. Early imaging showed slightly larger defects in six patients, equal defects in 24 patients, and slightly smaller defects in five patients. Ischemic/normal wall ratios were 0.67 +/- 0.16 at 15 minutes and 0.68 +/- 0.15 at 60 minutes.
There is no clinically significant difference between SPECT imaging performed at 15 minutes or 60 minutes after the injection of MIBI at stress. Furthermore, this study showed that it is feasible to obtain good-quality MIBI images even 15 minutes after the injection at stress.
先前的研究表明，静脉注射应激剂量的99mTc标记的甲氧基异丁基异腈（MIBI）后1至3小时，心肌存在“部分”再分布。这项前瞻性研究的目的是比较应激状态下注射后15分钟和60分钟进行的MIBI单光子发射计算机断层扫描（SPECT）成像在检测冠状动脉疾病方面的效果。
本研究纳入了35例冠状动脉疾病患者（26例行冠状动脉造影，23例201Tl检查结果呈阳性）。在峰值应激状态下注射25至30 mCi MIBI后15分钟开始SPECT成像（180度弧，32个角度，每视角25秒，使用高分辨率准直器）。患者按照相同方案并使用同一台γ相机在60分钟时再次成像。在静息状态下注射MIBI（25至30 mCi）48小时后，于75分钟时进行静息状态下的检查。图像（每位患者共分为19个节段）由两名不知情的观察者解读，用于患者诊断和节段比较。两种方案对患者的诊断相同：正常 = 3例，缺血 = 27例，瘢痕 = 5例。节段一致性（kappa = 0.90）为632/665（95.0%）。15分钟时进行的成像分别检测到正常、缺血和瘢痕节段413、189和63个，而60分钟时进行的成像分别检测到422、180和63个节段（差异无统计学意义）。将早期和延迟图像并列以主观比较缺损范围。早期成像显示6例患者的缺损略大，24例患者的缺损相等，5例患者的缺损略小。15分钟时缺血/正常心肌壁比值为0.67±0.16，60分钟时为0.68±0.15。
应激状态下注射MIBI后15分钟或60分钟进行的SPECT成像在临床上无显著差异。此外，本研究表明即使在应激状态下注射后15分钟也能获得高质量的MIBI图像。
