The importance of end-systole for optimal reconstruction protocol of coronary angiography with 16-slice multidetector computed tomography

Objectives: Multidetector-row computed tomography coronary images are usually analyzed in mid-diastole (MD). Because of slow coronary motion also in end-systole (ES), we evaluated the impact on image quality of including ES images and defined an efficient reconstruction protocol. Material and Methods: In 50 coronary multidetector-row computed tomography studies, 9 reconstructions (at 10% increments of I the RR interval) were graded for image quality. Multiple combinations of reconstructions were compared. Results: MD (60-70% of the RR interval) offered the best image quality. In 44% patients, the best reconstruction for ≥ 1 coronary was found in ES (20-30%). Their heart rate was higher (68.2 ± 9.9 bpm vs. 59.2 ± 8.8 bpm, P = 0.0014). Combining ES and MD consistently offered superior image quality and less nonevaluable vessels than even larger numbers of diastolic reconstructions alone. A combination of 2-3 reconstructions was most efficient. Adding more reconstructions did not significantly improve results. Conclusions: Combining ES and MD reconstructions reduces non-evaluable coronary arteries, particularly with higher heart rates. A protocol including 2-3 reconstructions is the most efficient.