基于冠状动脉CT血管成像定量钙化负荷的可行性研究

目的 探讨冠状动脉CT血管成像（CCTA）一站式计算冠状动脉钙化积分（CCTA-CS）和体积积分（CCTA-VS）的可行性,并分析其与心电门控CT平扫测得标准积分（CACS、VS）的相关性。 方法 本研究回顾性连续纳入1 075例受试者,男447例,女628例,平均年龄（56.79±9.49）岁。全部受试者均行包括门控CT平扫和CCTA的常规冠状动脉CT检查,测量CACS、VS、CCTA-CS和CCTA-VS。选择CACS与CCTA-CS均不为0的影像数据进行分析。采用组内相关系数（ICC）评估2名观察者间及观察者内测量CCTA-CS和CCTA-VS的一致性。采用线性相关分析与Bland-Altman检验分析CCTA与门控CT平扫所测评分的相关性与一致性。根据CACS对受试者进行心血管病危险度分层,并采用Kruskal-Wallis H检验比较多组间的CCTA-CS与CCTA-VS。采用二元Logistic回归分析影响钙化积分的危险因素。采用独立样本t检验比较CCTA和常规冠状动脉CT检查的有效辐射剂量（ED）。 结果 CACS和CCTA-CS不为0的受试者共437例。2名观察者间和观察者内测量的CCTA-CS和CCTA-VS的一致性均较好（均ICC>0.960）。CCTA-CS与CACS、CCTA-VS与VS均呈较好的正相关（r²=0.98、0.96,均P<0.05）。Bland-Altman检验结果显示CCTA与门控CT平扫所测评分间的一致性较高。不同危险分层病人的CCTA-CS和CCTA-VS差异均有统计学意义（均P<0.05）。Logistic回归分析显示高血压、糖尿病、高脂血症、吸烟史、脑血管病均为CACS、CCTA-CS的危险因素。CCTA检查的ED低于常规冠状动脉CT检查,Flash扫描可减少21.2%,Sequence扫描可减少18.6%。 结论 CCTA一站式测量可以精确定量钙化,测得的CCTA-CS、CCTA-VS与标准积分有较好的相关性,且能有效降低辐射剂量。

Feasibility study of calcium score quantitation based on coronary CT angiography

Objective To explore the feasibility of coronary CT angiography (CCTA) for calcium score (CCTA-CS) and volume score (CCTA-VS) one-stop quantitation, and to test the correlations between the measurements obtained from CCTA and the ECG gated non-enhanced CT. Methods All of 1 075 consecutive subjects were enrolled in this study retrospectively, 447 males and 628 females, average age 56.79±9.49 years. All subjects underwent routine coronary artery CT examinations, including gated non-enhanced CT and CCTA. These parameters of coronary artery calcium score (CACS), volume score (VS), CCTA-CS and CCTA-VS were measured. The image data with neither CACS nor CCTA-CS of 0 were selected and analyzed. The intra-class correlation coefficient (ICC) was used to evaluate the inter-group and intra-group consistency of CCTA-CS and CCTA-VS measured by 2 observers. Linear correlation analysis and Bland-Altman test were used to compare the correlation and consistency between the measurements obtained from CCTA and gated non-enhanced CT. The subjects were stratified for cardiovascular risk according to CACS, and the Kruskal-Wallis H test was used to compare CCTA-CS and CCTA-VS among multiple groups. Binary logistic regression was used to analyze the risk factors affecting the calcium score, and the independent sample t test was used to compare the effective dose(ED) between CCTA and routine coronary artery CT examination. Results There were 437 patients with neither CACS nor CCTA-CS of 0. The measurement of CCTA-CS and CCTA-VS between two observers and within the observers had a high degree of consistency (all ICC> 0.960). CCTA-CS and CACS, CCTA-VS and VS were all positively correlated(r²=0.98 and 0.96, both P<0.05). The Bland-Altman test showed high consistency between the scores measured by CCTA and gated non-enhanced CT. There were significant differences in CCTA-CS and CCTA-VS among the low,medium,and high risk stratification(all P<0.05). The logistic regression analysis showed the risk factors of CACS and CCTA-CS were hypertension, diabetes, hyperlipidemia, smoking history and cerebrovascular disease. The ED of CCTA examination was lower than routine coronary artery CT examination, Flash examination can reduce 21.2%, Sequence examination can reduce 18.6%. Conclusions CCTA one-stop examination can accurately quantify calcium plaques, and CCTA-CS and CCTA-VS showed good correlation with standard scores. This method can effectively reduce radiation dose.