Given current pretest probability (PTP) estimations tend to overestimate patients' risk for obstructive coronary artery disease, evaluation of patients' coronary artery calcium (CAC) is more... Show moreGiven current pretest probability (PTP) estimations tend to overestimate patients' risk for obstructive coronary artery disease, evaluation of patients' coronary artery calcium (CAC) is more precise. The value of CAC assessment with the Agatston score on cardiac computed tomography (CT) for risk estimation has been well indicated in patients with stable chest pain. CAC can be equally well assessed on routine non-gated chest CT, which is often available. This study aims to determine the clinical applicability of CAC assess- ment on non-gated CT in patients with stable chest pain compared with the classic Agat- ston score on gated CT. Consecutive patients referred for evaluation of the Agatston score, who had a previously performed non-gated chest CT for evaluation of noncardiac diseases, were included. CAC on non-gated CT was ordinally scored. Subsequently, patients were stratified according to CAC severity and PTP. The agreement and correla- tion between the classic Agatston score and CAC on non-gated CT were evaluated. The discriminative power for risk reclassification of both CAC assessment methods was assessed. Invasive coronary angiography was used as the gold standard, when available. A total of 140 patients aged between 30 and 88 years were included. The agreement between ordinally scored CAC and the Agatston score was excellent (k=0.82) and the correlation strong (r=0.94). Most patients (80%) with an intermediate PTP had no or mild CAC on non-gated CT. They were reclassified at low risk with 100% accuracy compared with invasive coronary angiography. Similarly, 86% of patients had an Agatston score <300. These patients were reclassified with 98% accuracy. In patients with high PTP, the accu- racy remained substantial and comparable, 94% and 89%, respectively. In conclusion, we believe this is the first study to assess the clinical applicability of CAC on non-gated CT in patients with stable chest pain, compared with the classic Agatston score. The agree- ment between methods was excellent and the correlation strong. Furthermore, CAC assessment on non-gated CT could reclassify patients' risk for obstructive coronary artery disease as accurately as could the classic Agatston score.(c) 2023 The Author(s). Published by Elsevier Inc.This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/) (Am J Cardiol 2023;208:92-100) Show less
BackgroundElevated coronary artery calcium (CAC) scores in subjects without prior atherosclerotic cardiovascular disease (ASCVD) have been shown to be associated with increased cardiovascular risk... Show moreBackgroundElevated coronary artery calcium (CAC) scores in subjects without prior atherosclerotic cardiovascular disease (ASCVD) have been shown to be associated with increased cardiovascular risk.ObjectivesThe authors sought to determine at what level individuals with elevated CAC scores who have not had an ASCVD event should be treated as aggressively for cardiovascular risk factors as patients who have already survived an ASCVD event.MethodsThe authors performed a cohort study comparing event rates of patients with established ASVCD to event rates in persons with no history of ASCVD and known calcium scores to ascertain at what level elevated CAC scores equate to risk associated with existing ASCVD. In the multinational CONFIRM (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter) registry, the authors compared ASCVD event rates in persons without a history of myocardial infarction (MI) or revascularization (as categorized on CAC scores) to event rates in those with established ASCVD. They identified 4,511 individuals without known coronary artery disease (CAC) who were compared to 438 individuals with established ASCVD. CAC was categorized as 0, 1 to 100, 101 to 300, and >300. Cumulative major adverse cardiovascular events (MACE), MACE plus late revascularization, MI, and all-cause mortality incidence was assessed using the Kaplan-Meier method for persons with no ASCVD history by CAC level and persons with established ASCVD. Cox proportional hazards regression analysis was used to calculate HRs with 95% CIs, which were adjusted for traditional cardiovascular risk factors.ResultsThe mean age was 57.6 ± 12.4 years (56% male). In total, 442 of 4,949 (9%) patients experienced MACEs over a median follow-up of 4 years (IQR: 1.7-5.7 years). Incident MACEs increased with higher CAC scores, with the highest rates observed with CAC score >300 and in those with prior ASCVD. All-cause mortality, MACEs, MACE + late revascularization, and MI event rates were not statistically significantly different in those with CAC >300 compared with established ASCVD (all P > 0.05). Persons with a CAC score <300 had substantially lower event rates.ConclusionsPatients with CAC scores >300 are at an equivalent risk of MACE and its components as those treated for established ASCVD. This observation, that those with CAC >300 have event rates comparable to those with established ASCVD, supplies important background for further study related to secondary prevention treatment targets in subjects without prior ASCVD with elevated CAC. Understanding the CAC scores that are associated with ASCVD risk equivalent to stable secondary prevention populations may be important for guiding the intensity of preventive approaches more broadly. Show less
