Lakkis N M, Mahmarian J J, Verani M S
Department of Medicine, Baylor College of Medicine, Methodist Hospital, Houston, Texas 77030, USA.
Am J Cardiol. 1995 Jul 15;76(3):107-11. doi: 10.1016/s0002-9149(99)80039-3.
Thallium-201 single photon emission computed tomography (SPECT) is superior to planar imaging for localizing native coronary stenoses, but has not yet been studied for assessing graft patency late after coronary artery bypass graft surgery (CABG). Accordingly, we studied 50 patients (40 males), aged 58 +/- 9 years (mean +/- SD), who presented for evaluation of angina (30 patients), atypical chest pain (20 patients), and other symptoms (9 patients), late after CABG (51 +/- 47 months). Patients with prior myocardial infarction were excluded. The mean ejection fraction was 58 +/- 17%. All patients underwent coronary angiography within 3 weeks of symptom-limited exercise thallium-201 SPECT. There were 119 grafts, of which 48 had > 50% stenosis by angiography. Thallium-201 SPECT detected 40 of these 48 (83%) stenosed grafts. The sensitivity of thallium-201 SPECT for detecting any graft stenosis was higher than that of the exercise electrocardiogram in patients with typical recurrent angina (84% vs 24%, p < 0.0001), as well as in those with atypical symptoms (70% vs 50%, p = 0.0039). The sensitivity of thallium-201 SPECT for correctly localizing the graft stenosis site was 82% for the left anterior descending, 92% for the right coronary, and 75% for the circumflex coronary artery. In conclusion, exercise thallium-201 SPECT is an excellent method to detect and localize graft stenosis late after CABG; it is far superior to the exercise electrocardiogram alone, both in patients with and without typical recurrent angina.
铊-201单光子发射计算机断层扫描（SPECT）在定位自身冠状动脉狭窄方面优于平面成像，但尚未用于评估冠状动脉旁路移植术（CABG）术后晚期的移植血管通畅情况。因此，我们研究了50例患者（40例男性），年龄58±9岁（均值±标准差），这些患者在CABG术后晚期（51±47个月）因心绞痛（30例患者）、非典型胸痛（20例患者）及其他症状（9例患者）前来评估。排除既往有心肌梗死的患者。平均射血分数为58±17%。所有患者在症状受限的运动铊-201 SPECT检查后3周内接受冠状动脉造影。共有119条移植血管，其中48条经血管造影显示狭窄>50%。铊-201 SPECT检测出这48条狭窄移植血管中的40条（83%）。铊-201 SPECT检测任何移植血管狭窄的敏感性在典型复发性心绞痛患者中高于运动心电图（84%对24%，p<0.0001），在非典型症状患者中也是如此（70%对50%，p = 0.0039）。铊-201 SPECT正确定位移植血管狭窄部位的敏感性，左前降支为82%，右冠状动脉为92%，回旋支冠状动脉为75%。总之，运动铊-201 SPECT是检测和定位CABG术后晚期移植血管狭窄的极佳方法；无论有无典型复发性心绞痛，它都远比单独的运动心电图优越。
