Coronary computed tomography angiography in the evaluation of intermediate risk asymptomatic individuals

Cardiovascular disease is still one of the main causes of death and an early identification of coronary artery disease (CAD) remains the primary step in clinical management of patients with cardiovascular risk factor. Coronary computed tomography angiography (CCTA) has shown high sensitivity in CAD detection and could be helpful as screening method. The purpose of this study was to assess the prevalence of coronary artery disease detected by CCTA in asymptomatic patients with an intermediate risk of CAD.

We retrospectively selected 185 asymptomatic patients with an intermediate Framingan Risk Score (mean age was 62.3 ± 12.4 years); all patients underwent CCTA, using 640-slice CT.

Atherosclerotic plaques were present in 112 out of 185 patients (60.5%); 56 subjects (30.2%) had mild stenosis, 49 (26.5%) moderate stenosis, only 3 patients (1.6%) had severe stenosis and in 4 cases (2.2%) the "blooming effect" did not allow for evaluation of the degree of stenosis. Among the positive cases, a high number of patients (44.6%) [50] showed coronary artery disease in one vessel, 33 patients (29.4%) in two vessels, 22 patients (19.6%) in three vessels and 5 patients in four vessels or more (4.5%). Patients with moderate stenosis were older, had hypertension in most cases, higher total cholesterol levels and more often were smokers. The radiation dose (mSv) dispensed to the patients was 3.7 ± 1.6 mSv.

High prevalence of coronary stenosis detected by low-dose CCTA in patients not properly classified by the traditional methods of risk stratification commonly used in clinical practice emphasizes the need to extend the risk stratification to other diagnostic tools with higher capability to detect CAD.