Prognostic value of semi-quantitative scoring systems for CCTA: a systematic review and meta-analysis

Semi-quantitative coronary computed tomography angiography (CCTA) scoring systems - including the Segment Involvement Score (SIS), Segment Stenosis Score (SSS), CT-adapted Leaman score (CT-LeSc), Leiden score, Coronary Artery Calcium Score (CACS) and the Coronary Artery Disease-Reporting and Data System (CAD-RADS);are used to quantify coronary atherosclerotic burden. However, their relative performance and suitability for standardized clinical application remain uncertain. We performed a systematic review and meta-analysis for studies reporting associations between semi-quantitative CCTA scores and major adverse cardiovascular events (MACE). Random-effects models were used to derive pooled hazard ratios (HRs) for SIS, SSS, CACS, CT-LeSc, and Leiden scores, and risk ratios (RRs) for CAD-RADS. Thirty-seven studies, examining 54,719 patients, were analysed, and all scoring systems were significantly associated with MACE. Among hard MACE predictors, SIS (HR 1.18, p ​< ​0.001) and SSS (HR 1.24, p ​< ​0.001) performed comparably, as did the anatomically weighted CT-LeSc (HR 1.10, p ​< ​0.001) and Leiden scores (HR 1.11, p ​< ​0.001). For broad MACE, both CAD-RADS (RR 1.71, p ​< ​0.001) and CACS (HR 1.73, p ​< ​0.001) categories showed similar stepwise gradients. Overall, all five semi-quantitative CCTA scoring systems demonstrated consistent and significant associations with hard cardiovascular events, and given broadly similar performance across metrics, simpler tools such as SIS or CAD-RADS may offer practical advantages for routine clinical use. Further within-cohort, head-to-head comparisons and evaluation of clinically actionable thresholds are warranted.