Department of Cardiology, Rambam Health Care Campus and the B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Eur J Nucl Med Mol Imaging. 2011 Oct;38(10):1917-25. doi: 10.1007/s00259-011-1856-3. Epub 2011 Jun 18.
Early risk stratification in patients with non-ST elevation acute coronary syndromes (NSTE-ACS) is important since the benefit from more aggressive and costly treatment strategies is proportional to the risk of adverse clinical events. In the present study we assessed whether hybrid single photon emission computed tomography (SPECT)/coronary computed tomography angiography (CCTA) technology could be an appropriate tool in stratifying patients with NSTE-ACS.
SPECT/CCTA was performed in 90 consecutive patients with NSTE-ACS. The Thrombolysis in Myocardial Infarction risk score (TIMI-RS) was used to classify patients as low- or high-risk. Imaging was performed using SPECT/CCTA to identify haemodynamically significant lesions defined as >50% stenosis on CCTA with a reversible perfusion defect on SPECT in the corresponding territory.
CCTA demonstrated at least one lesion with >50% stenosis in 35 of 40 high-risk patients (87%) as compared to 14 of 50 low-risk patients (35%; TIMI-RS<3; p<.0001). Of the 40 high-risk and 50 (16%) low-risk TIMI-RS patients, 16 (40%) and 8 (16%), respectively, had haemodynamically significant lesions (p=0.01). Patients defined as high-risk by a high TIMI-RS, a positive CCTA scan or both (n=45) resulted in a sensitivity of 95%, specificity of 49%, PPV of 35% and NPV of 97% for having haemodynamically significant coronary lesions. Those with normal perfusion were spared revascularization procedures, regardless of their TIMI-RS.
Noninvasive assessment of coronary artery disease by SPECT/CCTA may play an important role in risk stratification of patients with NSTE-ACS by better identifying the subgroup requiring intervention.
非 ST 段抬高型急性冠状动脉综合征（NSTE-ACS）患者的早期风险分层很重要，因为更积极和昂贵的治疗策略的获益与不良临床事件的风险成正比。在本研究中，我们评估了混合单光子发射计算机断层扫描（SPECT）/冠状动脉计算机断层血管造影（CCTA）技术是否可作为 NSTE-ACS 患者分层的合适工具。
对 90 例连续 NSTE-ACS 患者进行 SPECT/CCTA 检查。采用血栓形成溶栓治疗风险评分（TIMI-RS）将患者分为低危或高危。使用 SPECT/CCTA 进行影像学检查，以确定血流动力学显著病变，定义为 CCTA 上 >50%的狭窄和相应区域 SPECT 上的可逆灌注缺损。
与低危 TIMI-RS 患者（TIMI-RS<3）相比，40 例高危患者中至少有一个 >50%狭窄病变的患者有 35 例（87%），而 50 例低危患者中有 14 例（35%）（p<.0001）。在 40 例高危和 50 例（16%）低危 TIMI-RS 患者中，分别有 16 例（40%）和 8 例（16%）患者存在血流动力学显著病变（p=0.01）。根据 TIMI-RS 高、CCTA 扫描阳性或两者均阳性而定义为高危的患者（n=45），其对存在血流动力学显著冠状动脉病变的敏感性为 95%、特异性为 49%、阳性预测值为 35%、阴性预测值为 97%。那些灌注正常的患者无论其 TIMI-RS 如何，均可避免血运重建。
SPECT/CCTA 对冠状动脉疾病的非侵入性评估可能在 NSTE-ACS 患者的风险分层中发挥重要作用，通过更好地识别需要干预的亚组。
