Comparison Between Prospectively Electrocardiogram-Gated High-Pitch Mode and Retrospectively Electrocardiogram-Gated Mode for Dual-Source CT Coronary Angiography

Abstract

SummaryBackgroundWe aimed to report the image quality, relationship between heart rate and image quality, amount of contrast agent given to the patients and radiation doses in coronary CT angiography (CTA) obtained by using high-pitch prospectively ECG-gated “Flash Spiral” technique (method A) or retrospectively ECG-gated technique (method B) using 128×2-slice dual-source CT.Material/MethodsA total of 110 patients who were evaluated with method A and method B technique with a 128×2-detector dual-source CT device were included in the study. Patients were divided into three groups based on their heart rates during the procedure, and a relationship between heart rate and image quality were evaluated. The relationship between heart rate, gender and radiation dose received by the patients was compared.ResultsA total of 1760 segments were evaluated in terms of image quality. Comparison of the relationship between heart rate and image quality revealed a significant difference between heart rate <60 beats/min group and >75 beats/min group whereas <60 beats/min and 60–75 beats/min groups did not differ significantly. The average effective dose for coronary CTA was calculated as 1.11 mSv (0.47–2.01 mSv) for method A and 8.22 mSv (2.19–12.88 mSv) for method B.ConclusionsMethod A provided high quality images with doses as low as <1 mSv in selected patients who have low heart rates with a high negative predictive value to rule out coronary artery disease. Although method B increases the amount of effective dose, it provides high diagnostic quality images for patients who have a high heart rate and arrhythmia which makes it is difficult to obtain images.

Estimation and comparison of the radiation effective dose during coronary computed tomography angiography examinations on single-source 64-MDCT and dual-source 128-MDCT

“…This might be due to the use of a lower pitch (3.2 versus 3.4) and the use of a different conversion factor (0.017 mSv mGy -1 cm -1 ). In another study Koplay et al [37] reported the effective dose from a prospectively ECG-triggered high-pitch mode from dual-source 128-MDCT of 1.11 mSv (0.47-2.01 mSv). They used a pitch of 3.4 and a Somatom Technology Care kV with automatic mAs.…”

Anatomical Evaluation of the Pulmonary Veins and the Left Atrium Using Computed Tomography Before Catheter Ablation: Reproducibility of Measurements

“…Apart from imaging of the coronary arteries in various clinical scenarios [ 9 , 10 ], current applications of cardiac computed tomography can be extended onto coronary calcium scoring, planning of electrophysiological procedures, and, recently, to functional analysis of the myocardium [ 11 – 13 ]. CTA of the left atrium and pulmonary veins is easily tolerated by patients as the scanning time is usually less than 10 s when using the latest generation of scanners.…”