Departments of Cardiology and Nuclear Medicine, Isala Klinieken, Groot Wezenland 20, 8011 JW Zwolle, the Netherlands.
Radiology. 2013 Oct;269(1):77-83. doi: 10.1148/radiol.13122529. Epub 2013 Jun 20.
To assess the capability of a zero coronary artery calcium (CAC) score to help exclude flow-limiting coronary artery disease (CAD) in a homogeneous population with stable anginal complaints and a low-to-intermediate pretest likelihood.
The study protocol had institutional ethics committee approval, with written informed consent from all patients. Between 2009 and 2011, a total of 3501 consecutive stable patients without known CAD underwent prospectively simultaneous myocardial perfusion imaging and CAC scoring on a hybrid, 64-section single photon emission computed tomography (SPECT)/computed tomography (CT) scanner. In 868 (25%) of 3501 patients, the CAC score was zero, and these patients constituted the current study population. When feasible, additional coronary CT angiography was performed in those with abnormal SPECT findings. Clinical follow-up was recorded with regard to invasive coronary angiography, coronary revascularization, nonfatal myocardial infarction, or death. Results were analyzed by using descriptive statistics.
In 868 patients (mean age, 54 years ± 11 [standard deviation]; 610 [70%] female, 258 [30%] male), SPECT findings were normal in 766 (88%) and abnormal in 102 (12%), with equivocal results in 41 (5%), persistent defect in 35 (4%), and ischemia in 26 (3%). In the group with abnormal SPECT findings, additional coronary CT angiography was performed in 93 patients (91%), showing nonobstructive CAD in eight patients (9%) and normal coronary arteries in 85 patients (91%). In the other nine patients (9%), invasive angiography was used to exclude obstructive CAD. At a median follow-up of 17 months (25th percentile, 11; 75th percentile, 24 months), no coronary events were recorded.
A CAC score of zero in stable patients at low or intermediate risk excludes flow-limiting CAD. These findings support the possibility of CAC scoring as a simple and safe tool to select patients for additional testing or discharge, as recommended in the literature.
评估零冠状动脉钙评分（CAC）在具有稳定型心绞痛症状和低至中度术前可能性的同质人群中帮助排除限制血流的冠状动脉疾病（CAD）的能力。
该研究方案获得了机构伦理委员会的批准，并获得了所有患者的书面知情同意。在 2009 年至 2011 年期间，共有 3501 例连续的稳定型、无已知 CAD 的患者在一台混合式、64 层单光子发射计算机断层扫描（SPECT）/计算机断层扫描（CT）扫描仪上前瞻性地同时进行心肌灌注成像和 CAC 评分。在 3501 例患者中，868 例（25%）的 CAC 评分为零，这些患者构成了当前的研究人群。对于 SPECT 结果异常的患者，当可行时，还进行了额外的冠状动脉 CT 血管造影检查。记录了临床随访情况，包括侵入性冠状动脉造影、冠状动脉血运重建、非致死性心肌梗死或死亡。结果采用描述性统计进行分析。
在 868 例患者中（平均年龄 54 岁±11 岁[标准差]；610 例[70%]女性，258 例[30%]男性），766 例（88%）的 SPECT 结果正常，102 例（12%）异常，41 例（5%）结果不确定，35 例（4%）持续存在缺陷，26 例（3%）有缺血。在 SPECT 结果异常的患者中，93 例（91%）进行了额外的冠状动脉 CT 血管造影检查，其中 8 例（9%）有非阻塞性 CAD，85 例（91%）有正常的冠状动脉。在其他 9 例（9%）患者中，采用了有创血管造影术排除了阻塞性 CAD。在中位随访 17 个月（25%分位数，11；75%分位数，24 个月）时，没有发生冠状动脉事件。
稳定型低危或中危患者的 CAC 评分为零可排除限制血流的 CAD。这些发现支持 CAC 评分作为一种简单、安全的工具，用于选择患者进行额外的检查或出院，这与文献中的建议一致。
