ABSTRACT
BACKGROUND: Direct coronary arterial evaluation via computed tomography (CT) angiography is the most accurate noninvasive test for the diagnosis of coronary artery disease (CAD). However, diagnostic accuracy is limited in the setting of severe coronary calcification or stents. Ultra-high-resolution CT (UHR-CT) may overcome this limitation, but no rigorous study has tested this hypothesis. METHODS: The CORE-PRECISION is an international, multicenter, prospective diagnostic accuracy study testing the non-inferiority of UHR-CT compared to invasive coronary angiography (ICA) for identifying patients with hemodynamically significant CAD. The study will enroll 150 patients with history of CAD, defined as prior documentation of lumen obstruction, stenting, or a calcium score ≥400, who will undergo UHR-CT before clinically prompted ICA. Assessment of hemodynamically significant CAD by UHR-CT and ICA will follow clinical standards. The reference standard will be the quantitative flow ratio (QFR) with <0.8 defined as abnormal. All data will be analyzed in independent core laboratories. RESULTS: The primary outcome will be the comparative diagnostic accuracy of UHR-CT vs. ICA for detecting hemodynamically significant CAD on a patient level. Secondary analyses will focus on vessel level diagnostic accuracy, quantitative stenosis analysis, automated contour detection, in-depth plaque analysis, and others. CONCLUSION: CORE-PRECISION aims to investigate if UHR-CT is non-inferior to ICA for detecting hemodynamically significant CAD in high-risk patients, including those with severe coronary calcification or stents. We anticipate this study to provide valuable insights into the utility of UHR-CT in this challenging population and for its potential to establish a new standard for CAD assessment.
ABSTRACT
Resumo Fundamento A avaliação do Escore de Cálcio Coronariano (ECC) pode ser realizada por tomografia computadorizada sem contraste para prever eventos cardiovasculares, mas tem menor valor na estratificação de risco em pacientes sintomáticos. Objetivo Identificar e validar preditores de obstrução coronariana significativa (OCS) em pacientes sintomáticos sem calcificação da artéria coronária. Métodos Um total de 4258 participantes foram rastreados dos estudos CORE64 e CORE 320, nos quais foram avaliados pacientes encaminhados para angiografia invasiva, e do Quanta Registry que incluiu pacientes encaminhados para angiotomografia. Modelos de regressão logística avaliaram associações entre fatores de risco cardiovascular, ECC e OCS. Um nível de significância de 5% foi usado nas análises. Resultados Dos 509 participantes do estudo CORE, 117 (23%) apresentaram um ECC igual a zero; 13 (11%) pacientes sem cálcio coronariano apresentaram OCS. A ausência de cálcio coronariano correlacionou-se com idade mais jovem, sexo feminino, índice de massa corporal mais baixo, ausência de diabetes, e ausência de dislipidemia. O fato de ser fumante atual aumentou em 3,5 vezes a probabilidade de OCS e outros fatores de risco cardiovasculares não apresentaram associação significativa. Considerando os achados clínicos, um algoritmo para estratificar os pacientes com ECC igual a zero foi proposto, e tiveram desempenho limitado na coorte de validação (AUC 58; IC95% 43, 72). Conclusão Um perfil de risco cardiovascular mais baixo está associado a um ECC igual a zero em pacientes de alto risco. Tabagismo é o preditor mais forte de OCS em pacientes com ausência de cálcio coronariano.
Abstract Background Coronary artery calcium (CAC) scanning can be performed using non-contrast computed tomography to predict cardiovascular events, but has less value for risk stratification in symptomatic patients. Objective To identify and validate predictors of significant coronary obstruction (SCO) in symptomatic patients without coronary artery calcification. Methods A total of 4,258 participants were screened from the CORE64 and CORE320 studies that enrolled patients referred for invasive angiography, and from the Quanta Registry that included patients referred for coronary computed tomography angiography (CTA). Logistic regression models evaluated associations between cardiovascular risk factors, CAC, and SCO. An algorithm to assess the risk of SCO was proposed for patients without CAC. Significance level of 5% was used in the analyses. Results Of the 509 participants of the CORE study, 117 (23%) had zero coronary calcium score; 13 (11%) patients without CAC had SCO. Zero calcium score was related to younger age, female gender, lower body mass index, no diabetes, and no dyslipidemia. Being a current smoker increased ~3.5 fold the probability of SCO and other CV risk factors were not significantly associated. Considering the clinical findings, an algorithm to further stratify zero calcium score patients was proposed and had a limited performance in the validation cohort (AUC 58; 95%CI 43, 72). Conclusion A lower cardiovascular risk profile is associated with zero calcium score in a setting of high-risk patients. Smoking is the strongest predictor of SCO in patients without CAC.