ABC | Volume 110, Nº5, May 2018

Original Article Atherosclerotic Plaque in Patients with Zero Calcium Score at Coronary Computed Tomography Angiography Fabíola Santos Gabriel, 1,3 Luiz Flávio Galvão Gonçalves, 2,3 Enaldo Vieira de Melo, 1 Antônio Carlos Sobral Sousa, 1,4,5 Ibraim Masciarelli Francisco Pinto, 6 Sara Melo Macedo Santana, 3 Carlos José Oliveira de Matos, 1,4 Maria Júlia Silveira Souto, 1,4 Flávio Mateus do Sacramento Conceição, 1,4 Joselina Luzia Menezes Oliveira 1,4,5,6,7 Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS), 1 São Cristóvão, SE - Brazil Centro de Pesquisas da Fundação São Lucas, 2 Aracaju, SE - Brazil Clínica de Medicina Nuclear de Diabetes – CLIMEDI, 3 Aracaju, SE - Brazil Departamento de Medicina - Universidade Federal de Sergipe (UFS), 4 São Cristóvão, SE - Brazil Centro de Ensino e Pesquisa e Laboratório de Ecocardiografia (ECOLAB) do Hospital e Fundação São Lucas, 5 Aracaju, SE - Brazil Instituto Dante Pazzanese de Cardiologia, 6 São Paulo, SP - Brazil Centro de Ensino e Pesquisa da Fundação São Lucas, 7 Aracaju, SE - Brazil Mailing Address: Fabíola Santos Gabriel • Av. Dr. Francisco Moreira, 220, Bl. F, Apt. 04. Postal Code 49047-335, Ponto novo, Aracaju, SE – Brazil E-mail: fabiola.s.gabriel@gmail.com Manuscript received May 01, 2017, revised manuscript November 12, 2017, accepted November 22, 2017 DOI: 10.5935/abc.20180063 Abstract Background: In view of the high mortality for cardiovascular diseases, it has become necessary to stratify the main risk factors and to choose the correct diagnostic modality. Studies have demonstrated that a zero calcium score (CS) is characteristic of a low risk for cardiovascular events. However, the prevalence of individuals with coronary atherosclerotic plaques and zero CS is conflicting in the specialized literature. Objective: To evaluate the frequency of patients with coronary atherosclerotic plaques, their degree of obstruction and associated factors in patients with zero CS and indication for coronary computed tomography angiography (CCTA). Methods: This is a cross-sectional, prospective study with 367 volunteers with zero CS at CCTA in four diagnostic imaging centers in the period from 2011 to 2016. A significance level of 5% and 95% confidence interval were adopted. Results: The frequency of atherosclerotic plaque in the coronary arteries in 367 patients with zero CS was 9.3% (34 individuals). In this subgroup, mean age was 52 ± 10 years, 18 (52.9%) were women and 16 (47%) had significant coronary obstructions (> 50%), with involvement of two or more segments in 4 (25%) patients. The frequency of non‑obese individuals (90.6% vs 73.9%, p = 0.037) and alcohol drinkers (55.9% vs 34.8%, p = 0.015) was significantly higher in patients with atherosclerotic plaques, with an odds ratio of 3.4 for each of this variable. Conclusions: The frequency of atherosclerotic plaque with zero CS was relatively high, indicating that the absence of calcification does not exclude the presence of plaques, many of which obstructive, especially in non-obese subjects and alcohol drinkers. (Arq Bras Cardiol. 2018; 110(5):420-427) Keywords: Cardiovascular Diseases/mortality; Plaque, Atherosclerotic; Coronary Artery Disease/diagnosis; Calcium Signaling; Coronary, Angiotomography; Risk Factors. Introduction Coronary artery disease (CAD) are the leading cause of death in the world, including in Brazil. Many methods for CAD diagnosis, risk stratification of patients and indication of revascularization are currently available. 1 One of the greatest challenges of routine cardiology practice is to determine the best method to detect subclinical CAD. Coronary computed tomography angiography (CCTA) is a predominantly anatomical test with excellent diagnostic accuracy in detecting obstructive and nonobstructive lesions as compared with coronary angiography, which is considered the gold standard method for this purpose. Also, CCTA may provide relevant information regarding atheroma composition according to radiological density. 2,3 The role of coronary calcification, identified by calcium score (CS), used for classification of patients into a higher risk for cardiovascular events, is well known. Although individuals with a zero CS may also have atherosclerotic plaques, 4,5 its presence has not been associated with increased risk for future cardiovascular events. 4 Nevertheless, despite these results reported in international studies, we have not found Brazilian studies published on this specific subject. In fact, studies’ results may not be replicated in different sociodemographic or anthropometric contexts, or even in different healthcare conditions. Reproducibility of a study is a sine qua non for an extensive validation of its results. 420