de Vries Jessica, DeJongste Mike J L, Jessurun Gillian A J, Jager Pieter L, Staal Michiel J, Slart Riemer H J A
Faculty of Medicine, University Medical Center Groningen and University of Groningen, the Netherlands.
Nucl Med Commun. 2006 Oct;27(10):791-4. doi: 10.1097/01.mnm.0000237984.46844.42.
The combination of angina pectoris, angiographically normal coronary arteries, and a positive exercise stress test (EST) is referred to as cardiac syndrome X. However, a large group of patients suspected of syndrome X reveals a normal exercise stress test and weakens the diagnosis of syndrome X. Previous studies demonstrated an impaired coronary flow reserve on ammonia positron emission tomography (PET) in patients with syndrome X.
To evaluate the coronary flow reserve in patients suspected of syndrome X with positive and negative EST findings, using [(13)N]ammonia PET as the diagnostic aid.
Forty-two patients with chest pain and a normal coronary angiography, were analysed by exercise stress testing (EST) and the dypyridamole stress test (DST) on [(13)N]ammonia PET. Two subgroups were predefined, based on outcome of EST: an EST positive and negative group. A normal control group was used as the reference method.
A total of 24 (57%) out of 42 patients had significant ST-T changes (EST positive). [(13)N]ammonia PET showed a significantly lower rest flow in the EST positive and EST negative group compared to controls (P<0.001 and P=0.0028, respectively). DST [(13)N]ammonia PET perfusion was significantly reduced in flow in both the EST positive and EST negative groups (P<0.001 both), as was the DST/rest [(13)N]ammonia perfusion reserve (P<0.001 for both), compared to normal controls.
PET demonstrates a reduced coronary flow reserve in patients suspected of syndrome X, irrespective of the EST findings.
心绞痛、冠状动脉造影正常以及运动负荷试验（EST）阳性同时出现被称为心脏X综合征。然而，一大群疑似X综合征的患者运动负荷试验结果正常，这削弱了X综合征的诊断。先前的研究表明，X综合征患者在氨正电子发射断层扫描（PET）上存在冠状动脉血流储备受损的情况。
使用[（13）N]氨PET作为诊断辅助手段，评估运动负荷试验结果为阳性和阴性的疑似X综合征患者的冠状动脉血流储备。
对42例胸痛且冠状动脉造影正常的患者进行运动负荷试验（EST）和双嘧达莫负荷试验（DST），并采用[（13）N]氨PET进行分析。根据EST结果预先定义两个亚组：EST阳性组和EST阴性组。使用正常对照组作为参考方法。
42例患者中共有24例（57%）出现显著的ST-T改变（EST阳性）。与对照组相比，[（13）N]氨PET显示EST阳性组和EST阴性组的静息血流均显著降低（分别为P<0.001和P=0.0028）。与正常对照组相比，EST阳性组和EST阴性组的DST[（13）N]氨PET灌注血流均显著降低（均为P<0.001），DST/静息[（13）N]氨灌注储备也显著降低（均为P<0.001）。
无论EST结果如何，PET均显示疑似X综合征患者的冠状动脉血流储备降低。
