Redefining NSTE-ACS risk assessment: The synergistic power of CT-enhanced GRACE 2.0 score for advanced prognosis

The Global Registry of Acute Coronary Events (GRACE) 2.0 risk score has been recommended in guidelines to orient therapeutic strategy and risk assessment for non-ST-segment elevation acute coronary syndrome (NSTE-ACS). To evaluate the incremental value of computed tomography (CT)-based coronary atherosclerosis plaque burden to GRACE 2.0 score in refining the intermediate-term prognostic accuracy and risk stratification for emergency NSTE-ACS. In this prospective cohort study, from January 2017 to January 2021, NSTE-ACS individuals were enrolled and randomly divided into a developing and validation sets by 7:3. We estimated the correlations between GRACE 2.0 score and CT findings. The primary outcomes are the incremental prognostic value of CT for the GRACE 2.0 score's efficacy in predicting 3-year mortality or myocardial infarction (MI). A total of 1248 consecutive NSTE-ACS patients undergoing CT scans were prospectively included. The risk of 3-year mortality or MI was greater in the higher CACS category (HR, 2.31 [95% CI, 1.45-3.67]), SIS category (HR, 3.37 [95% CI, 2.36-4.82]) and luminal stenosis degree (HR, 1.69 [95% CI, 1.15-2.48]) stratified by CAD-RADS (coronary artery disease reporting and Data System) 2.0 than in the lower ones. The CT-GRACE model integrating CACS category, SSS and GRACE 2.0 risk score was compared with the GRACE 2.0 risk score to evaluate their discrimination and reclassification ability in predicting 3-year mortality or MI. The C-statistics were 0.889 (0.842, 0.937) and 0.742 (0.659, 0.826) in the validation set, respectively (ΔAUC=0.147, P < 0.001). Coronary atherosclerosis plaque burden features could provide more meaningful information for GRACE 2.0 risk score to evaluate the intermediate-term prognosis for emergency NSTE-ACS.