Prospectively ECG-triggered high-pitch coronary angiography with third-generation dual-source CT at 70 kVp tube voltage: Feasibility, image quality, radiation dose, and effect of iterative reconstruction

Abstract Background Low tube voltage reduces radiation exposure in coronary CT angiography (CTA). Using 70 kVp tube potential has so far not been possible because CT systems were unable to provide sufficiently high tube current with low voltage. Objective We evaluated feasibility, image quality (IQ), and radiation dose of coronary CTA using a third-generation dual-source CT system capable of producing 450 mAs tube current at 70 kVp tube voltage. Methods Coronary CTA was performed in 26 consecutive patients with suspected coronary artery disease, selected for body weight Results Mean age was 62 ± 9 years (46% males; mean body mass index, 27.7 ± 3.8 kg/m 2 ; mean heart rate, 54 ± 5 beats/min). Mean dose-length product was 20.6 ± 1.9 mGy × cm; mean estimated effective radiation dose was 0.3 ± 0.03 mSv. Diagnostic IQ was found in 365 of 367 (FBP) and 366 of 367 (IR) segments ( P nonsignificant). IQ was rated “excellent” in 53% (FBP) and 86% (IR) segments ( P  = .001) and “nondiagnostic” in 2 (FBP) and 1 segment (IR) ( P nonsignificant). Mean IQ score was lesser in FBP vs IR (1.5 ± 0.4 vs 1.1 ± 0.2; P P Conclusion In patients