Department of Cardiology, The Heart Center, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
Eur Radiol. 2018 Oct;28(10):4077-4085. doi: 10.1007/s00330-018-5418-y. Epub 2018 Apr 25.
Diagnostic accuracy of conventional coronary CT angiography (CCTA) may be compromised by blooming artifacts from calcifications or stents. Blooming artifacts may be reduced by subtraction coronary CT angiography (CCTA) in which non-contrast and contrast CT data sets are subtracted digitally. We tested whether CCTA in patients with severe coronary calcification or stents reduces the number of false-positive stenosis evaluations compared with CCTA.
In this study, 180 symptomatic patients scheduled for invasive coronary angiography (ICA) were prospectively enrolled and CT scanned (2013-2016) at three international centers. CCTA, and CCTA data sets were reconstructed. Target segments were defined as motion-free coronary segments with a suspected stenosis (> 50% of lumen) potentially due to blooming of either calcium or stents. Target segments were evaluated with respect to misregistration artifacts from the CCTA reconstruction process, in which case evaluation was omitted. CCTA and CCTA were compared with ICA. Primary outcome measure was the frequency of false positives by CCTA versus CCTA to identify > 50% coronary stenosis by ICA on a per-segment level.
After exclusion of 76 patients, 104 (14% females) with mean age 67 years and median Agatston score 852 were included. There were 136 target segments with misregistration and 121 target segments without. Accuracy calculations in target segments without misregistration showed a reduction of the false positives from 72% [95% confidence interval (CI): 63-80%] in CCTA to 33% (CI:25-42%) in CCTA, at the expense of 7% (CI:3-14%) false negatives in CCTA.
In severely calcified coronary arteries or stents, CCTA reduces the false-positive rate in well-aligned, calcified or stent segments suspected of significant stenosis on CCTA. Nevertheless, misregistration artifacts are frequent in CCTA.
• A high calcium-score reduces the diagnostic accuracy in patients scanned with cardiac CT. • These patients would normally need an invasive angiogram for diagnosis. • In this prospective, multicenter study, subtraction CT, when evaluable, reduces false-positive stenosis evaluations. • Subtraction coronary CT angiography may, when evaluable, reduce excessive downstream testing.
常规冠状动脉 CT 血管造影（CCTA）的诊断准确性可能因钙化或支架的 blooming 伪影而受到影响。通过数字减去非对比和对比 CT 数据集，可以减少 blooming 伪影。我们测试了在严重冠状动脉钙化或支架的患者中，与 CCTA 相比，减去冠状动脉 CT 血管造影（CCTA）是否减少了假阳性狭窄评估的数量。
本研究前瞻性纳入了 180 名因疑似狭窄（> 50%管腔）而计划行有创冠状动脉造影（ICA）的症状性患者，并在三个国际中心进行了 CT 扫描（2013-2016 年）。重建 CCTA 和 CCTA 数据集。靶段定义为运动无狭窄的冠状动脉段，因钙或支架的 blooming 而可能存在狭窄（> 50%管腔）。靶段评估了 CCTA 重建过程中的配准伪影，如果存在这种情况，则省略评估。比较了 CCTA 和 CCTA 与 ICA。主要观察指标是 CCTA 与 CCTA 相比，在每段水平上识别出> 50%冠状动脉狭窄的假阳性率。
排除 76 例患者后，纳入了 104 例（14%为女性）患者，平均年龄 67 岁，中位 Agatston 评分 852。有 136 个靶段存在配准伪影，121 个靶段不存在。在不存在配准伪影的靶段中，计算出的准确性显示，CCTA 的假阳性率从 72%（95%置信区间[CI]：63-80%）降至 CCTA 的 33%（CI：25-42%），但 CCTA 的假阴性率增加了 7%（CI：3-14%）。
在严重钙化的冠状动脉或支架中，在 CCTA 上怀疑存在严重狭窄的钙化或支架的对准良好的靶段中，CCTA 减少了假阳性率。然而，在 CCTA 中，配准伪影很常见。
·高钙评分会降低接受心脏 CT 扫描的患者的诊断准确性。·这些患者通常需要进行有创血管造影术进行诊断。·在这项前瞻性、多中心研究中，当可评估时，减去 CT 可减少假阳性狭窄评估。·当可评估时，减去冠状动脉 CT 血管造影术可能会减少过度的下游检查。
