Low kilovolt “prospective ECG-triggering” vs. “retrospective ECG-gating” coronary CTA: comparison of image quality and radiation dose

Background: to compare image quality and radiation doses of low kilovolt (kv) “prospective ecg-triggering” (pt) and standard “retrospective ecg-gating” (rg) coronary computed tomography (ct) angiography. materials and methods: a total of 101 consecutive patients (76 males, 25 females; mean age: 55.44 ± 8.28 years) with low-to-intermediate risk status for coronary artery disease and with a body mass index (bmi) of <30 kg/m² were prospectively included in the study. the images were acquired with a 64-detector (128-slice) ct using the tube current modulation technique. the pt ct technique (100 kv, heart rate [hr]<70) was applied in 59 patients, while the rg ct technique (120 kv, hr≥70-90) was applied in 42 patients. the study was approved by the ethics committee. all patients provided informed written consent. results: no significant difference was found between age, sex and bmi of both groups (p > 0.05). the mean image quality score was 2.87 ± 0.25 for the low kv pt ct technique and 2.73 ± 0.31 for the rg ct technique, which was statistically significant (p < 0.05). no statistically significant difference was found between groups for signal-noise and contrast -noise ratios (p > 0.05). the mean effective dose was 1.43 ± 0.3 msv for low kv pt ct technique and 8.20±2.36 msv for the rg ct technique (p < 0.001). conclusion: in the low kv pt ct technique, the radiation dose is significantly reduced without loss of image quality. this technique can reliably be used in patients with bmi<30 kg/m² and hr less than 70 bpm.