Coronary Artery Disease and Structural Heart Disease Department, Institute of Cardiology, Alpejska 42 St, 04-628 Warsaw, Poland.
Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St, 29425 Charleston, SC, USA.
J Cardiovasc Comput Tomogr. 2017 Sep-Oct;11(5):397-403. doi: 10.1016/j.jcct.2017.08.004. Epub 2017 Aug 15.
CT-FFR is an area of growing interest in the field of cardiac imaging. However, the specific anatomic location distal to a lesion of interest where CT-FFR should be computed to yield the most valid results has not been examined. This study investigated the most appropriate anatomic location distal to a coronary artery stenosis for obtaining CT-FFR measurements.
73 patients (60 ± 9 years; 58% male) with at least one coronary lesion with 40-90% stenosis on coronary CTA (either a 2 × 128 slice or a 2 × 192 slice dual-source CT scanner) underwent stress cardiac magnetic resonance (CMR) perfusion imaging for inducible ischemia. 133 coronary arteries and corresponding myocardial territories were analyzed. The most appropriate anatomic location for predicting lesion-specific ischemia via CT-FFR (cFFR version 1.4, Siemens) was determined as either the distance from the lesion of interest or as a multiple of the reference vessel diameter distal to the minimum lumen area (MLA).
Inducible myocardial ischemia was found on MRI in 24 (18.1%) vessels/corresponding myocardial territories. The area under the ROC curve was A) 0.866 for CT-FFR measurement locations distal to the MLA expressed as a multiple of the reference diameter, B) 0.854 when expressed as a distance (mm) distal to the MLA, C) 0.803 for CT-FFR values measured in the distal vessel, and D) 0.725 according to stenosis severity on coronary CTA (A vs B p = 0.093; A vs D p = 0.003; A vs C p = 0.019; B vs D p = 0.006; B vs C p = 0.061; C vs D p = 0.082). The most optimal thresholds for agreement of CT-FFR with the reference CMR perfusion were at 41 mm or 10.9 times the proximal reference diameter distal to the MLA.
Our results suggest that the best agreement of CT-FFR with the reference CMR perfusion study is provided when CT-FFR values are computed at 41 mm or 10.9 times the proximal reference diameter distal to the MLA.
CT-FFR 是心脏成像领域日益关注的领域。然而，在计算最有效的 CT-FFR 结果时，尚不清楚感兴趣的病变远端的具体解剖位置。本研究调查了获得 CT-FFR 测量值时冠状动脉狭窄远端最合适的解剖位置。
73 例患者（60±9 岁；58%为男性），至少有一处冠状动脉狭窄程度为 40-90%的病变，这些病变通过冠状动脉 CTA（2×128 层或 2×192 层双源 CT 扫描仪）检测。对所有患者行应激心脏磁共振（CMR）灌注成像，以评估是否存在缺血。共分析了 133 支冠状动脉及其相应的心肌区域。通过 CT-FFR（cFFR 版本 1.4，西门子）预测特定病变缺血的最佳解剖位置，被确定为距感兴趣病变的距离或距最小管腔面积（MLA）的参考血管直径的倍数。
在 24 个（18.1%）血管/相应的心肌区域中发现了 MRI 诱导的心肌缺血。ROC 曲线下面积为 A）MLA 远端以参考直径倍数表示的 CT-FFR 测量位置为 0.866，B）MLA 远端以距离（mm）表示的 CT-FFR 测量位置为 0.854，C）远端血管内测量的 CT-FFR 值为 0.803，D）冠状动脉 CTA 上的狭窄严重程度为 0.725（A 与 B 的 p 值=0.093；A 与 D 的 p 值=0.003；A 与 C 的 p 值=0.019；B 与 D 的 p 值=0.006；B 与 C 的 p 值=0.061；C 与 D 的 p 值=0.082）。与参考 CMR 灌注最一致的 CT-FFR 值的最佳阈值为 MLA 远端 41mm 或近端参考直径的 10.9 倍。
我们的结果表明，当在 MLA 远端距离近端参考直径 41mm 或 10.9 倍处计算 CT-FFR 值时，CT-FFR 与参考 CMR 灌注研究的一致性最佳。
