Abstract：
BACKGROUND: Cardiac computed tomography quantification of extracellular volume fraction (CT-ECV) is an emerging biomarker of myocardial fibrosis which has demonstrated high reproducibility, diagnostic and prognostic utility. However, there has been wide variation in the CT-ECV protocol in the literature and useful disease cut-offs are yet to be established. The objectives of this meta-analysis were to describe mean CT-ECV estimates and to estimate the effect of CT-ECV protocol parameters on between-study variation.
METHODS: We conducted a meta-analysis of studies assessing CT-ECV in healthy and diseased participants. We used meta-analytic methods to pool estimates of CT-ECV and performed meta-regression to identify the contribution of protocol parameters to CT-ECV heterogeneity.
RESULTS: Thirteen studies had a total of 248 healthy participants who underwent CT-ECV assessment. Studies of healthy participants had high variation in CT-ECV protocol parameters. The pooled estimate of CT-ECV in healthy participants was 27.6% (95%CI 25.7%-29.4%) with significant heterogeneity (I2 = 93%) compared to 50.2% (95%CI 46.2%-54.2%) in amyloidosis, 31.2% (28.5%-33.8%) in severe aortic stenosis and 36.9% (31.6%-42.3%) in non-ischaemic dilated cardiomyopathies. Meta-regression revealed that CT protocol parameters account for approximately 25% of the heterogeneity in CT-ECV estimates.
CONCLUSIONS: CT-ECV estimates for healthy individuals vary widely in the literature and there is significant overlap with estimates in cardiac disease. One quarter of this heterogeneity is explained by differences in CT-ECV protocol parameters. Standardization of CT-ECV protocols is necessary for widespread implementation of CT-ECV assessment for diagnosis and prognosis.
METHODS: We conducted a meta-analysis of studies assessing CT-ECV in healthy and diseased participants. We used meta-analytic methods to pool estimates of CT-ECV and performed meta-regression to identify the contribution of protocol parameters to CT-ECV heterogeneity.
RESULTS: Thirteen studies had a total of 248 healthy participants who underwent CT-ECV assessment. Studies of healthy participants had high variation in CT-ECV protocol parameters. The pooled estimate of CT-ECV in healthy participants was 27.6% (95%CI 25.7%-29.4%) with significant heterogeneity (I2 = 93%) compared to 50.2% (95%CI 46.2%-54.2%) in amyloidosis, 31.2% (28.5%-33.8%) in severe aortic stenosis and 36.9% (31.6%-42.3%) in non-ischaemic dilated cardiomyopathies. Meta-regression revealed that CT protocol parameters account for approximately 25% of the heterogeneity in CT-ECV estimates.
CONCLUSIONS: CT-ECV estimates for healthy individuals vary widely in the literature and there is significant overlap with estimates in cardiac disease. One quarter of this heterogeneity is explained by differences in CT-ECV protocol parameters. Standardization of CT-ECV protocols is necessary for widespread implementation of CT-ECV assessment for diagnosis and prognosis.
摘要：
背景：细胞外体积分数的心脏计算机断层扫描定量（CT-ECV）是心肌纤维化的新兴生物标志物，已证明具有高可重复性，诊断和预后效用。然而,文献中的CT-ECV方案差异很大,有用的疾病界限尚未确定.这项荟萃分析的目的是描述平均CT-ECV估计值，并估计CT-ECV方案参数对研究间变异的影响。
方法：我们对健康和患病参与者的CT-ECV评估研究进行了荟萃分析。我们使用荟萃分析方法汇集CT-ECV的估计值，并进行荟萃回归以确定方案参数对CT-ECV异质性的贡献。
结果：13项研究共有248名健康参与者接受了CT-ECV评估。健康参与者的研究在CT-ECV方案参数上有很大差异。健康参与者的CT-ECV的汇总估计值为27.6%（95CI25.7%-29.4%），具有显著的异质性（I2=93%），而淀粉样变性为50.2%（95CI46.2%-54.2%）。重度主动脉瓣狭窄占31.2％（28.5％-33.8％），非缺血性扩张型心肌病占36.9％（31.6％-42.3％）。Meta回归显示，CT方案参数约占CT-ECV估计异质性的25％。
结论：文献中健康个体的CT-ECV估计值差异很大，与心脏病的估计值存在显著重叠。这种异质性的四分之一由CT-ECV协议参数的差异解释。CT-ECV方案的标准化对于广泛实施CT-ECV评估以进行诊断和预后是必要的。
方法：我们对健康和患病参与者的CT-ECV评估研究进行了荟萃分析。我们使用荟萃分析方法汇集CT-ECV的估计值，并进行荟萃回归以确定方案参数对CT-ECV异质性的贡献。
结果：13项研究共有248名健康参与者接受了CT-ECV评估。健康参与者的研究在CT-ECV方案参数上有很大差异。健康参与者的CT-ECV的汇总估计值为27.6%（95CI25.7%-29.4%），具有显著的异质性（I2=93%），而淀粉样变性为50.2%（95CI46.2%-54.2%）。重度主动脉瓣狭窄占31.2％（28.5％-33.8％），非缺血性扩张型心肌病占36.9％（31.6％-42.3％）。Meta回归显示，CT方案参数约占CT-ECV估计异质性的25％。
结论：文献中健康个体的CT-ECV估计值差异很大，与心脏病的估计值存在显著重叠。这种异质性的四分之一由CT-ECV协议参数的差异解释。CT-ECV方案的标准化对于广泛实施CT-ECV评估以进行诊断和预后是必要的。
