SPC365

Influence of Age on the Diagnostic Value of Coronary Artery Calcium Score for Ruling Out Coronary Stenosis in Symptomatic Patients

Session: Comunicações Orais - Sessão 29 - Score cálcio coronário
Speaker: Francisco Albuquerque

Congress: CPC 2023
Topic: B. Imaging
Theme: 03. Imaging
Subtheme: 03.2 Computed Tomography
Session Type: Comunicações Orais
FP Number: ---
Authors: Francisco Albuquerque; Pedro Lopes; Pedro Freitas; Pedro de Araújo Gonçalves; João Presume; Sara Guerreiro; João Abecasis; Ana Coutinho Santos; Carla Saraiva; Miguel Mendes; Hugo Marques; António Ferreira

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong>Background: </strong>The 2021 Guideline for the Evaluation of Chest Pain supports the use of coronary artery calcium (CAC) score as a reasonable first-line test to identify patients with a low likelihood of obstructive coronary artery disease (CAD) who may not require additional testing (class IIa, LOE B). However, a recent study from a large cohort of Northern European patients raised concerns about the added diagnostic value of CAC=0 in younger patients. The aim of this study was to assess the influence of age on the value of CAC=0 in symptomatic patients undergoing coronary computed tomography angiography (CCTA).</span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong>Methods: </strong><span style="color:black">We conducted a two-center cross-sectional study assessing symptomatic patients with suspected CAD who underwent CAC score and CCTA. </span><span style="color:black">Key exclusion criteria were age </span><span style="color:black">&lt; 30 years, known CAD, suspected acute coronary syndrome, or symptoms other than chest pain or dyspnea</span><span style="color:black">. </span><span style="color:black">Pretest probability of obstructive CAD was calculated based on age, sex and symptom typicality, according to the guideline-recommended method</span>. <span style="color:black">Obstructive CAD was defined as any luminal stenosis </span>&ge;50% on CCTA. The diagnostic likelihood ratios and negative predictive values (NPV) were used to assess the diagnostic value of a CAC score of 0 to rule out obstructive CAD.</span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="color:black">Results:</span></strong><span style="color:black"> A total of 2043 patients (mean age 60 </span><span style="font-family:Symbol"><span style="color:black">&plusmn;</span></span><span style="color:black"> 11 years, 60% women) of whom 990 (48.5%) had a CAC score of 0 were included in the analysis. Symptom</span> <span style="color:black">characteristics were: 38% non-anginal chest pain, 30% atypical angina, 19% dyspnea, and 13% typical chest pain. Overall, the </span><span style="color:black">prevalence of obstructive CAD was 12.8% (n=262). Pretest probability of obstructive CAD increased progressively with age, from 6.0% in patients young than 50 years to 20.7% in those 70 years or older. Contrariwise, the prevalence of patients with a CAC score = 0 decreased from 77% in patients younger than 50 years, to 26% in those who where 70 years or older. </span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:black">The added diagnostic value of a CAC score = 0 was lower in younger patients, with negative likelihood ratios ranging from 0.36 (64% decrease in the likelihood of CAD) in patients younger than 50 years, to 0.09 and 0.10 (~90% decrease in the likelihood of CAD) in those aged 60-69 years and 70 years or older, respectively &ndash; Figure.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:black">Despite this, the prevalence of obstructive CAD among patients with a CAC score = 0 was low across all age groups: 2.4% (i.e., NPV = 97.6%) in those younger than 50 years, 3.0% (NPV = 97.0%) among those aged 50-59 years, 1.5% (NPV = 98.5%) in patients between 60-69 years, and 2.0% (NPV = 98.0%) among those 70 years or older.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="color:black">Conclusions: </span></strong><span style="color:black">In a cohort of symptomatic patients </span><span style="color:black">undergoing CCTA for suspected CAD, the added diagnostic value of a CAC score of zero decreases significantly at younger ages. However, this &ldquo;diminishing return&rdquo; of CAC in younger patients if offset by their lower pretest probabilities, yielding high negative predictive values independently of age.</span></span></span></p>