Tc-99m Glucarate for chest pain triage in emergency room.

描述(由申请人提供)：区分急性冠脉综合征(ACS)和非心源性胸痛是急诊科临床医生面临的主要诊断挑战。心肌灌注成像的研究已经证明了对急性冠脉综合征患者进行风险分层的重要信息。然而，这种方法在有冠心病(CAD)病史的患者中的价值有限，因为这些患者通常会有异常的静息血流灌注模式，从而无法区分陈旧性脑梗塞和新的缺血事件。99mTc-葡萄糖酸盐不能发现陈旧性心脏病发作，因此，对有冠心病病史的疑似急性冠脉综合征患者，99mTc-葡萄糖酸盐在特异性方面具有优势。~(99m)Tc-葡萄糖酸盐作为放射性药物诊断显像剂用于诊断急性心肌梗死已有十多年的历史。以前，这种药物被认为是针对坏死性心肌梗死的。然而，最近的临床前研究表明，在缺血的情况下，即使在没有坏死的情况下，99mTc-葡萄糖摄取也会增加。这种扩展的特异性导致了这样的假设，即这种显像剂可以用于准确评估诊断不明确的胸痛患者中是否存在急性冠脉综合征。拟议的II期临床试验的主要目的是证明，候选核成像产品99mTC-葡萄糖酸盐可以用于急诊科设置的有冠心病病史的胸痛患者的ACS诊断。通过与临床出院诊断的比较，得出99mTc-葡萄糖酸盐在急诊科诊断急性冠脉综合征的准确性。该建议的具体目的是：1.对100例疑似急性冠脉综合征但无明显心肌梗死征象且有冠状动脉疾病史的胸痛患者进行99mTc-葡萄糖酸盐心脏显像的多点临床试验。2.以临床标准出院诊断为对照，确定99mTc-葡萄糖酸盐显像的准确性。这项研究的结果可以为明确诊断冠心病患者的急性冠脉综合征提供技术进步。这不仅应该导致对这些患者的早期诊断和分类，而且应该导致更好的卫生保健资源管理。

DESCRIPTION (provided by applicant): Differentiating acute coronary syndrome (ACS) from noncardiac chest pain is the primary diagnostic challenge for clinicians in the emergency department. Studies of myocardial perfusion imaging have demonstrated important information for risk- stratifying stable post-ACS patients. However, this method is of limited value in patients with prior history of coronary heart disease (CAD), since these patients will often have abnormal resting perfusion patterns precluding the ability to differentiate old infarcts from new ischemic events. 99m Tc-glucarate does not detect old heart attacks, and thus, should provide an advantage in the specificity for imaging suspected ACS patients with previous CAD. 99m Tc-glucarate has been in development as a radiopharmaceutical diagnostic imaging agent for the diagnosis of acute myocardial infarct (AMI) for more than a decade. Previously the agent was thought to be specific for necrotic myocardium or MI. However, more recent preclinical studies suggested that 99m Tc-glucarate uptake is increased in the setting of ischemia, even in the absence of necrosis. This expanded specificity has led to the hypothesis that this imaging agent could be used to accurately assess the presence of ACS in the chest-pain patient with equivocal diagnosis. The broad aim of the proposed phase II clinical trial is to demonstrate that the nuclear imaging product candidate, 99mTc-glucarate, can be used in the diagnosis of ACS in chest pain patients with prior history of coronary heart disease in the setting of the emergency department. The accuracy of diagnosis of ACS in the emergency department with 99mTc-glucarate will be obtained by comparison to the clinical discharge diagnosis. Specific aims of the proposal are: 1. Conduct a multi-site clinical trial of cardiac imaging with 99mTc-glucarate in 100 chest pain patients suspected of ACS, but with no obvious signs of MI and having prior coronary artery disease. 2. Determine the accuracy of 99m Tc-glucarate imaging compared to standard clinical discharge diagnosis. Results from this research could provide a technological advancement in definitive diagnosis of acute coronary syndrome in patients with know coronary heart disease. This should not only lead to early diagnosis and triage of these patients but also should lead to better health care resource management.