Department of Radiology, Kaohsiung Veterans General Hospital, No. 386, Ta-Chung Dazhong 1st Road, Kaohsiung City, 813414, Taiwan.
Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, No.155, Sec.2, Linong Street, Taipei, 11221, Taiwan.
BMC Cardiovasc Disord. 2023 Mar 27;23(1):158. doi: 10.1186/s12872-023-03162-6.
Coronary artery calcification (CAC) burden assessed by Agatston score (AS) is currently recommended to stratify patients at risk for future acute coronary syndrome (ACS). Besides the CAC burden, the biostructure of CAC may also play a vital role in the vulnerability of CAC, which CT radiomics could reveal. Propensity-score matching of the traditional risk factors and CAC burden between the ACS and asymptomatic groups could radically remove biases and allow the exploration of characteristic features of CAC in ACS.
We retrospectively identified 77 patients with ACS who had a CAC scan before percutaneous coronary intervention between 2016 and 2019. These 77 patients were one-to-two propensity-score matched for traditional risk factors of ACS and AS ranks to select 154 subjects from 2890 asymptomatic subjects. A validation cohort of 30 subjects was also enrolled. Radiomics features of each plaque were extracted and averaged in each person. Conditional logistic regression and area-under-curve analysis were used for statistical analysis.
A higher number of coronary segments involved, lower mean, median, first quartile, and standard deviation of attenuation, and increased kurtosis of attenuation of CAC were associated with the ACS group compared to the control group (p < 0.05 for all). Multivariable analysis showed that the lower median attenuation (OR = 0.969, p < 0.001) and higher Kurtosis (OR = 18.7, p < 0.001) were associated with the ACS group. The median attenuation and kurtosis significantly increase across AS ranks 1 to 4 (p = 0.001). The AUC of kurtosis (0.727) and median attenuation (0.66) were both significantly higher than that of the standard AS (AUC = 0.502) and the number of TRF (AUC = 0.537). The best cut-off of kurtosis at 2.74 yielded an accuracy of 74%, and the cut-off of median attenuation at 196 yielded an accuracy of 68%. The accuracy of kurtosis was 64%, and the accuracy of median attenuation was 55% in the validation cohort.
After propensity-matching traditional risk factors and CAC burden, CT radiomics highlighted that lower median attenuation and higher kurtosis were the CAC characteristics of vulnerable plaques. These features improve the understanding of the biomechanics of CAC evolution and enhance the value of CAC scan in ACS risk assessment.
目前，通过 Agatston 评分（AS）评估冠状动脉钙化（CAC）负担，用于对未来急性冠状动脉综合征（ACS）风险患者进行分层。除 CAC 负担外，CAC 的生物结构也可能在 CAC 的易损性中发挥重要作用，而 CT 放射组学可以揭示这一点。在 ACS 组和无症状组之间，通过传统危险因素和 CAC 负担的倾向评分匹配，可以从根本上消除偏差，并可以探索 ACS 中 CAC 的特征。
我们回顾性地确定了 2016 年至 2019 年间接受经皮冠状动脉介入治疗前 CAC 扫描的 77 名 ACS 患者。这些患者根据 ACS 的传统危险因素和 AS 等级进行一对一的倾向评分匹配，以从 2890 名无症状患者中选择 154 名患者。还纳入了一个 30 名患者的验证队列。提取并平均了每个人的每个斑块的放射组学特征。采用条件逻辑回归和曲线下面积分析进行统计分析。
与对照组相比，ACS 组的受累冠状动脉节段数更多，平均、中位数、第一四分位数和衰减的标准差更低，以及 CAC 衰减的峰度增加（所有 p 值均<0.05）。多变量分析表明，中位衰减值较低（OR=0.969，p<0.001）和峰度较高（OR=18.7，p<0.001）与 ACS 组相关。中位衰减值和峰度随着 AS 等级 1 到 4 的升高而显著增加（p=0.001）。峰度的 AUC（0.727）和中位衰减的 AUC（0.66）均显著高于标准 AS（AUC=0.502）和 TRF 数量（AUC=0.537）。峰度的最佳截断值为 2.74，准确率为 74%，中位衰减的截断值为 196，准确率为 68%。验证队列中峰度的准确率为 64%，中位衰减的准确率为 55%。
在进行传统危险因素和 CAC 负担的倾向评分匹配后，CT 放射组学突出显示，较低的中位衰减值和较高的峰度是易损斑块 CAC 的特征。这些特征有助于了解 CAC 演变的生物力学，并增强 CAC 扫描在 ACS 风险评估中的价值。
