Department of Imaging and Medicine and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Centre for Cardiovascular Science, University of Edinburgh, Scotland, UK.
Department of Imaging and Medicine and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
J Cardiovasc Comput Tomogr. 2018 Sep-Oct;12(5):379-384. doi: 10.1016/j.jcct.2018.05.003. Epub 2018 May 7.
Non-invasive fractional flow reserve derived from coronary CT angiography (FFR) has been shown to be predictive of lesion-specific ischemia as assessed by invasive fractional flow reserve (FFR). However, in practice, clinicians are often faced with an abnormal distal FFR in the absence of a discrete obstructive lesion. Using quantitative plaque analysis, we sought to determine the relationship between an abnormal whole vessel FFR (V-FFR) and quantitative measures of whole vessel atherosclerosis in coronary arteries without obstructive stenosis.
FFR was calculated in 155 consecutive patients undergoing coronary CTA with ≥25% but less than 70% stenosis in at least one major epicardial vessel. Semi-automated software was used to quantify plaque volumes (total plaque [TP], calcified plaque [CP], non-calcified plaque [NCP], low-density non-calcified plaque [LD-NCP]), remodeling index [RI], maximal contrast density difference [CDD] and percent diameter stenosis [%DS]. Abnormal V-FFR was defined as a minimum value of ≤0.75 across the vessel (at the most distal region where FFR was computed).
Vessels with abnormal V-FFR had higher per-vessel TP (554 vs 331 mm), CP (59 vs 25 mm), NCP (429 vs 295 mm), LD-NCP (65 vs 35 mm) volume and maximum CDD (21 vs 14%) than those with normal V-FFR (median, p < 0.05 for all). Using a multivariate analysis to adjust for CDD and %DS, all measures of plaque volume were predictive of abnormal V-FFR (OR 2.09, 1.36, 1.95, 1.95 for TP, CP, NCP and LD-NCP volume, respectively; p < 0.05 for all).
Abnormal V-FFR in vessels without obstructive stenosis is associated with multiple markers of diffuse non-obstructive atherosclerosis, independent of stenosis severity. Whole vessel FFR may represent a novel measure of diffuse coronary plaque burden.
从冠状动脉 CT 血管造影（FFRCT）得出的无创性分流量比（FFR）已被证明可预测通过有创性分流量比（FFR）评估的特定病变的缺血。然而，在实践中，临床医生经常在没有离散阻塞性病变的情况下遇到异常的远端 FFR。我们使用定量斑块分析，旨在确定在没有阻塞性狭窄的情况下，整个血管 FFR（V-FFR）异常与整个血管动脉粥样硬化的定量测量之间的关系。
在至少一个主要心外膜血管中存在≥25%但<70%狭窄的 155 例连续接受冠状动脉 CTA 的患者中计算 FFR。使用半自动软件来定量斑块体积（总斑块[TP]、钙化斑块[CP]、非钙化斑块[NCP]、低密度非钙化斑块[LD-NCP]）、重塑指数[RI]、最大对比度密度差[CDD]和直径狭窄百分比[%DS]。异常 V-FFR 定义为血管中最低值≤0.75（在计算 FFR 的最远端区域）。
V-FFR 异常的血管具有更高的每血管 TP（554 比 331mm）、CP（59 比 25mm）、NCP（429 比 295mm）、LD-NCP（65 比 35mm）体积和最大 CDD（21 比 14%）比 V-FFR 正常的血管（中位数，p<0.05 所有）。使用多元分析调整 CDD 和%DS，所有斑块体积指标均预测 V-FFR 异常（TP、CP、NCP 和 LD-NCP 体积的 OR 分别为 2.09、1.36、1.95 和 1.95；p<0.05 所有）。
在没有阻塞性狭窄的血管中，异常的 V-FFR 与弥漫性非阻塞性动脉粥样硬化的多个标志物相关，与狭窄严重程度无关。整个血管 FFR 可能代表弥漫性冠状动脉斑块负担的新指标。
