60 kVp Coronary CT Angiography as a Screening Tool on Asymptomatic Patients: An Initial Experience

To investigate the feasibility of using 60 kVp coronary CT angiography (CCTA) combined with deep learning-based CT reconstruction as a screening tool on asymptomatic patients.

A total of 156 asymptomatic patients (body mass index, 24.4 ± 2.2 kg/m 2 ) with at least one coronary artery disease (CAD) risk factor were prospectively enrolled for taking an experimental ultra-low dose 60 kVp CCTA followed by a routine 120 kVp CCTA. Stenosis detection, plaque analysis, and image quality assessment were performed on both scans, with 120 kVp CCTA serving as the reference.

The mean effective dose and mean contrast medium (CM) dosage were 0.4 ± 0.1 mSv and 27.0 ± 3.2 mL, respectively, for 60 kVp CCTA, corresponding to a 91.5% and 50.0% reduction as compared with 120 kVp CCTA. In both analyses for all plaque types and noncalcific plaques, the sensitivity, specificity, and accuracy in stenosis detection were >92% with 60 kVp CCTA on per-segment, per-vessel, and per-patient basis, and in particular, the negative predictive value was ≥ 97%. However, compared to 120 kVp CCTA, 60 kVp CCTA led to a significant overestimation in plaque volume and stenosis severity ( P <0.01), as well as inferior subjective scores regarding vessel and lumen delineation ( P <0.05).

Despite overestimation in plaque volume and stenosis severity, 60 kVp CCTA showed excellent stenosis detection capability with ultra-low radiation dose and reduced CM dosage that may potentially be adopted as a screening tool for asymptomatic patients in routine practice.