Application of Low Tube Potentials in CCTA

Objectives The aim of this study was to assess the use of low tube potentials for coronary computed tomography angiography (CCTA) in worldwide clinical practice and its influence on radiation exposure, contrast agent volume, and image quality. Background CCTA is frequently used in clinical practice. Lowering of tube potential is a potent method to reduce radiation exposure and to economize contrast agent volume. Methods CCTAs of 4,006 patients from 61 international study sites were analyzed regarding very-low (≤80 kVp), low (90 to 100 kVp), conventional (110 to 120 kVp), and high (≥130 kVp) tube potentials. The impact on dose-length product (DLP) and contrast agent volume was analyzed. Image quality was determined by evaluation of the diagnostic applicability and assessment of the objective image parameters signal-to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR). Results When compared with conventional tube potentials, low tube potentials were used in 56% of CCTAs (≤80 kVp: 9%; 90 to 100 kVp: 47%), which varied among sites from 0% to 100%. Tube potential reduction was associated with low–cardiovascular risk profile, low body mass index (BMI), and new-generation scanners. Median radiation exposure was lowered by 68% or 50% and median contrast agent volume by 25% or 13% for tube potential protocols of ≤80 kVp or 90 to 100 kVp when compared with conventional tube potentials, respectively (all p Conclusions This large international registry confirms the feasibility of tube potential reduction in clinical practice leading to lower radiation exposure and lower contrast volumes. The current registry also demonstrates that this strategy is still underused in daily practice. (PROspective multicenter registry on radiaTion dose Estimates of cardiac CT angIOgraphy iN daily practice in 2017 [PROTECTION-VI]; NCT02996903)