Fragasso G, Rossetti E, Dosio F, Gianolli L, Pizzetti G, Cattaneo N, Fazio F, Chierchia S L
Division of Cardiology, University of Milan, Instituto Scientifico H San Raffaele, Italy.
Eur Heart J. 1996 Oct;17(10):1482-7. doi: 10.1093/oxfordjournals.eurheartj.a014710.
To evaluate the stress-myocardial perfusion pattern in patients with angina, positive exercise test and angiographically smooth coronary arteries (syndrome X).
Prospective study.
Twenty-five consecutive patients (seven males, mean age 54 +/- 8 years) with typical angina, positive exercise test, normal coronary arteries and no inducible spasm, underwent stress-redistribution thallium-201 myocardial perfusion scintigraphy. Thirty-two consecutive patients (14 males, mean age 49 +/- 7 years) with atypical chest pain and negative exercise test, undergoing stress-redistribution thallium scan, served as controls.
Exercise was discontinued for angina and/or ST-segment depression after 12 +/- 3 min. Thallium stress images revealed 40 hypoperfused segments in 27 patients (77%); after 4 h, 16 of these segments had completely normalized, 10 remained unchanged, six exhibited partial reperfusion and eight worsened. Twenty-four patients (69%) exhibited thallium reverse redistribution in 33 segments. Thirty-four patients (97%) had at least one hypoperfused segment in one of the two scintigraphic phases. Of the 24 patients with reverse redistribution, eight also underwent stress-rest 99m Tc-MIBI SPECT: six exhibited reduced tracer uptake that was present at rest, but not on stress images, in the same segments showing thallium reverse redistribution. Thallium stress images revealed four hypoperfused segments in three controls (9%); at redistribution, one segment normalized, two remained unchanged and one exhibited partial reperfusion. Additionally, there were four new underperfused segments appearing on redistribution in four patients (13%). Overall, there were seven controls (22%) with at least one hypoperfused myocardial segment in one of the two scintigraphic phases.
Our study confirms that perfusion abnormalities are present in most syndrome X patients. Additionally, the data show that reverse redistribution (a perfusion defect that develops or becomes more evident on delayed imaging) is a common finding in these patients. The mechanisms of the phenomenon remain obscure: we suggest that it is due to inhomogeneous perfusion, and the hyperaemic response induced by exercise masks resting underperfusion of certain areas.
评估心绞痛、运动试验阳性且冠状动脉造影显示血管光滑（X综合征）患者的应激 - 心肌灌注模式。
前瞻性研究。
连续25例患者（7例男性，平均年龄54±8岁），有典型心绞痛、运动试验阳性、冠状动脉正常且无诱发痉挛，接受了静息 - 再分布铊 - 201心肌灌注闪烁显像。连续32例患者（14例男性，平均年龄49±7岁），有非典型胸痛且运动试验阴性，接受静息 - 再分布铊扫描，作为对照。
运动12±3分钟后因心绞痛和/或ST段压低而终止。铊应激显像显示27例患者（77%）有40个灌注减低节段；4小时后，其中16个节段完全恢复正常，10个节段无变化，6个节段部分再灌注，8个节段病情恶化。24例患者（69%）在33个节段出现铊反向再分布。34例患者（97%）在两个闪烁显像阶段中的一个阶段至少有一个灌注减低节段。在24例有反向再分布的患者中，8例还接受了静息 - 负荷99m锝 - 甲氧基异丁基异腈单光子发射计算机断层显像（SPECT）：6例在显示铊反向再分布的相同节段出现静息时示踪剂摄取减少，但负荷显像时无此表现。铊应激显像显示3例对照患者（9%）有4个灌注减低节段；再分布时，1个节段恢复正常，2个节段无变化，1个节段部分再灌注。此外，4例患者（13%）在再分布时有4个新的灌注减低节段出现。总体而言，7例对照患者（22%）在两个闪烁显像阶段中的一个阶段至少有一个心肌灌注减低节段。
我们的研究证实大多数X综合征患者存在灌注异常。此外，数据显示反向再分布（在延迟显像时出现或变得更明显的灌注缺损）在这些患者中是常见表现。该现象的机制仍不清楚：我们认为这是由于灌注不均匀，运动诱发的充血反应掩盖了某些区域的静息灌注减低。
