Najm Y C, Maisey M N, Clarke S M, Fogelman I, Curry P V, Sowton E
Division of Radiological Sciences, United Medical School, Guy's Hospital, London, U.K.
Int J Cardiol. 1990 Jan;26(1):93-102. doi: 10.1016/0167-5273(90)90252-z.
The evaluation of technetium-99m methoxy isobutylisonitrile for the diagnosis of coronary artery disease requires comparative validation against thallium-201, the established perfusion imaging agent. We have compared myocardial and lung uptake of both radiotracers following maximal exercise in 52 patients: 40 with angiographically proven coronary disease. Qualitative and quantitative image analysis showed the diagnostic sensitivity of technetium-99m methoxy isobutylisonitrile to compare favourably with that of thallium-201 as reflected by the mean number of ischaemic segments identified: 5.6 +/- 2.5 vs 4.8 +/- 2.1 by qualitative analysis, and 5.7 +/- 3.2 vs 5.0 +/- 2.6 segments by quantitative analysis. More reversibly ischaemic segments per patient were identified with technetium-99m methoxy isobutylisonitrile than with thallium-201: 3.6 +/- 2.3 vs 1.8 +/- 1.9. There was a higher exercise myocardial to background count ratio with technetium-99m methoxy isobutylisonitrile: 3.16:1 vs 2.58:1, and the mean exercise lung uptake normalised to left ventricular uptake ('lung index'), was lower for technetium-99m methoxy isobutylisonitrile than for thallium-201 (36 +/- 8% vs 40 +/- 10%). Five of the six patients with abnormal elevation of the thallium-201 exercise lung index also had elevation of the technetium-99m methoxy isobutylisonitrile exercise lung index, and all had extensive coronary artery disease. These results indicate that technetium-99m methoxy isobutylisonitrile is at least as effective as thallium-201 for detecting exercise induced myocardial ischaemia. However, technetium-99m methoxy isobutylisonitrile provides a better image quality and may be a more sensitive marker of defect reversibility. For both radiotracers lung uptake is increased with extensive coronary artery disease and measurement of this variable provides prognostic information.
评估锝-99m甲氧基异丁基异腈用于诊断冠状动脉疾病需要与已确立的灌注显像剂铊-201进行对比验证。我们比较了52例患者在最大运动后两种放射性示踪剂在心肌和肺部的摄取情况：其中40例经血管造影证实患有冠状动脉疾病。定性和定量图像分析显示，锝-99m甲氧基异丁基异腈的诊断敏感性与铊-201相当，定性分析确定的缺血节段平均数可反映这一点：分别为5.6±2.5节段和4.8±2.1节段；定量分析分别为5.7±3.2节段和5.0±2.6节段。与铊-201相比，使用锝-99m甲氧基异丁基异腈发现每位患者有更多可逆性缺血节段：分别为3.6±2.3节段和1.8±1.9节段。锝-99m甲氧基异丁基异腈运动心肌与本底计数比更高：分别为3.16:1和2.58:1，并且锝-99m甲氧基异丁基异腈相对于左心室摄取的平均运动肺部摄取（“肺指数”）低于铊-201（分别为36±8%和40±10%）。铊-201运动肺指数异常升高的6例患者中有5例锝-99m甲氧基异丁基异腈运动肺指数也升高，且均患有广泛冠状动脉疾病。这些结果表明，锝-99m甲氧基异丁基异腈在检测运动诱发的心肌缺血方面至少与铊-201一样有效。然而，锝-99m甲氧基异丁基异腈提供了更好的图像质量，并且可能是缺损可逆性的更敏感标志物。对于两种放射性示踪剂，广泛冠状动脉疾病时肺部摄取增加，测量这一变量可提供预后信息。
