201铊、99m锝-替曲膦与多巴酚丁胺磁共振成像用于识别冬眠心肌的比较

Comparison of 201Tl, 99mTc-tetrofosmin, and dobutamine magnetic resonance imaging for identifying hibernating myocardium.

作者信息

Gunning M G, Anagnostopoulos C, Knight C J, Pepper J, Burman E D, Davies G, Fox K M, Pennell D J, Ell P J, Underwood S R

机构信息

Departments of Cardiac Imaging, Cardiology, and Cardiac Surgery, Royal Brompton Hospital, and the Institute of Nuclear Medicine, University College London Medical School, London, UK.

出版信息

Circulation. 1998 Nov 3;98(18):1869-74. doi: 10.1161/01.cir.98.18.1869.

DOI:10.1161/01.cir.98.18.1869

PMID:9799206

Abstract

BACKGROUND

Both radionuclide perfusion tracers and contractile response to dobutamine have been used to identify hibernating myocardium. The aim was to compare 201Tl (thallium) single photon emission CT (SPECT), 99mTc-tetrofosmin (tetrofosmin) SPECT, and dobutamine cine MRI for identifying regions of reversible myocardial dysfunction.

METHODS AND RESULTS

Thirty patients with 3-vessel coronary artery disease and impaired left ventricular function (mean LVEF, 24.0%; SD, 8.3%) scheduled for coronary bypass grafting were recruited. All underwent rest/dobutamine stress (5 to 10 microg . kg-1 . min-1) cine MRI, stress/rest tetrofosmin SPECT, and stress/redistribution and separate-day rest/redistribution thallium SPECT before surgery. Stress/redistribution thallium SPECT and resting MRI were repeated after surgery. In a 9-segment model, SPECT images were scored visually for tracer uptake, which was also measured from a polar plot of myocardial counts. MRI was scored visually for endocardial motion, myocardial thickening, and thickness. Five patients died before follow-up, and 2 declined postoperative investigation. In the remaining 23 patients, mean LVEF increased from 24.0% (SD, 8.3%) to 29.7% (SD, 11.1%) (P<0.05). Of 207 segments analyzed, 145 had significantly abnormal wall motion before surgery, and 82 of these improved function after revascularization. The criteria for predicting recovery of severely hypokinetic segments on preoperative imaging were tracer uptake graded "moderately reduced" or better, or positive inotropic response on dobutamine MRI. Late-rest thallium images showed the highest sensitivity (76%), compared with stress-redistribution thallium (68%) and rest tetrofosmin (66%) (P<0.05). All 3 tracer techniques were nonspecific (44%, 51%, and 49%, respectively). Redistribution of thallium after the resting injection was insensitive (18%) but highly specific (83%). Inotropic response to dobutamine was also insensitive (50%) but specific (81%).

CONCLUSIONS

Radionuclide uptake is a sensitive but nonspecific predictor of myocardial functional recovery, whereas dobutamine MRI is specific but insensitive.

摘要

背景

放射性核素灌注示踪剂和对多巴酚丁胺的收缩反应均已用于识别冬眠心肌。目的是比较201Tl（铊）单光子发射计算机断层扫描（SPECT）、99mTc-替曲膦（替曲膦）SPECT和多巴酚丁胺电影磁共振成像用于识别可逆性心肌功能障碍区域。

方法与结果

招募了30例计划进行冠状动脉搭桥术的三支血管冠状动脉疾病且左心室功能受损（平均左心室射血分数，24.0%；标准差，8.3%）的患者。所有患者在手术前均接受静息/多巴酚丁胺负荷（5至10μg·kg-1·min-1）电影磁共振成像、负荷/静息替曲膦SPECT以及负荷/再分布和隔日静息/再分布铊SPECT检查。术后重复进行负荷/再分布铊SPECT和静息磁共振成像检查。在一个9节段模型中，对SPECT图像进行视觉评分以评估示踪剂摄取情况，也从心肌计数的极坐标图中进行测量。对磁共振成像进行视觉评分以评估心内膜运动、心肌增厚和厚度。5例患者在随访前死亡，2例拒绝术后检查。在其余23例患者中，平均左心室射血分数从24.0%（标准差，8.3%）增加至29.7%（标准差，11.1%）（P<0.05）。在分析的207个节段中，145个节段在手术前有明显异常的壁运动，其中82个节段在血运重建后功能改善。术前成像预测严重运动减弱节段恢复的标准为示踪剂摄取分级为“中度降低”或更好（即摄取较好），或多巴酚丁胺磁共振成像上有正性变力反应。延迟静息铊图像显示出最高的敏感性（76%），相比之下，负荷-再分布铊（68%）和静息替曲膦（66%）（P<0.05）。所有3种示踪剂技术均缺乏特异性（分别为44%、51%和49%）。静息注射后铊的再分布敏感性较低（18%）但特异性较高（83%）。对多巴酚丁胺的变力反应敏感性也较低（50%）但特异性较高（81%）。