Marked Reduction of Effective Radiation Dose in Patients Undergoing CT Coronary Angiography using Prospective ECG Gating

This is an initial report on the use of the recently introduced whole-heart 320-slice computed tomography (CT) scanner for noninvasive coronary angiography compared with conventional coronary angiography (CCA). Whole-heart CT avoids overscanning and overranging as necessary for helical coronary CT acquisitions thereby significantly reducing the effective radiation dose. Twelve patients with suspected coronary artery disease (4 women, 8 men; mean age 64.6 ± 11 years) have undergone coronary CT angiography using a 320-slice scanner (Aquilion ONE, Toshiba; 0.35 s gantry rotation time, 120 kV, and 350 – 450 mA) prior to clinically indicated CCA. CT images were manually reconstructed in motion-free phases with 0.5-mm slice thickness and 0.25-mm slice increment. Independent blinded assessment of CT and CCA (using quantitative analysis) was performed to detect significant (at least 50%) diameter stenoses. Of the 12 patients, in 8 patients, single-heart beat CT acquisition was performed, resulting in an effective dose of 5.6 ± 1.1 mSv and an image reconstruction window length of 175 msec. In the other 4 patients, because of higher heart rates, 2 or 3 heart beats were used for acquisition, resulting in higher radiation exposure (on average 17 mSv) and the possibility to perform multisegment reconstruction with improved temporal resolution (88 and 58 msec image reconstruction windows, respectively). Per-patient sensitivity and specificity for CT compared to CCA were 100%. Per-vessel sensitivity and specificity were 88% and 95%, respectively. Intraindividual comparison of CT with CCA revealed a nonsignificantly smaller effective radiation dose (9.4 ± 7.2 mSv vs. 10.5 ± 5.3 mSv, p<0.69) but significantly smaller contrast agent amount (80 ±0 ml vs. 107.3 ± 17.8 ml, p<0.01) for 320-slice CT. Whole-heart CT significantly reduces the contrast agent amount compared to CCA while radiation exposure is reduced in patients with slow heart rates. This initial report also indicates that diagnostic accuracy of coronary CT angiography using up to 320 simultaneous detector rows remains high as compared with CCA as the reference standard.

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First head-to-head comparison of effective radiation dose from low-dose 64-slice CT with prospective ECG-triggering versus invasive coronary angiography

Heart ◽

10.1136/hrt.2008.162420 ◽

2009 ◽

Vol 95 (20) ◽

pp. 1656-1661 ◽

Cited By ~ 71

Author(s):

B A Herzog ◽

C A Wyss ◽

L Husmann ◽

O Gaemperli ◽

I Valenta ◽

...

Keyword(s):

Radiation Dose ◽

Coronary Angiography ◽

Low Dose ◽

Invasive Coronary Angiography ◽

Effective Radiation Dose ◽

Effective Radiation ◽

Prospective Ecg Triggering

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How Can an Updated 320 Multi Detector Computed Tomography Low Dose Protocol Help in Assessment of Coronary Heart Disease

QJM ◽

10.1093/qjmed/hcab106.048 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Ahmed Samir Ibrahim ◽

Asst. Emad Hamed Abd-Eldayem ◽

Mostafa Mohammed Osman

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Radiation Dose ◽

Radiation Doses ◽

Ecg Gating ◽

Coronary Ct ◽

Prospective Ecg Gating ◽

The Difference ◽

Artery Disease ◽

Effective Radiation

Abstract Background Coronary artery disease (CAD) is the single most common cause of death in the developed world, responsible for about I in every 5 deaths. The morbidity, mortality, and socioeconomic importance of this disease make timely accurate diagnosis and cost-effective management of CAD of the utmost importance. The recent years showed an overall increase in the use of CT for imaging of the heart and coronary arteries, coronary CT angiography is a rapidly growing technique that offers distinct advantages over traditional imaging techniques. However, because of rapid growth of this technique, radiation dose safety has been placed under the spotlight. Integration of dosesaving techniques will go a long way in maintaining diagnostic image quality and improving patient safety. Objectives The purpose of our study is the assessment of coronary artery disease by 320 MDCT and its capabilities of maintaining the quality of images and dose reduction improving patient safety. Patients and Methods This study was performed at New Cairo Police Hospital (Radiology department) and at Center in East Cairo, From October 2018 to October 2019, a total of 39 patients who had referred for CTCA for suspicion of coronary artery disease enrolled in our prospective study. Results In this study we used MDCT 64 with retrospective ECG-gating in 25.6% of patients (10 patients) and MDCT 320 with Retrospective ECG-gating was used in 25.6% (10 patients) and with Prospective ECG-gating in 48.8% (19 patients).we compared the radiation dose between prospective ECG-gating and retrospective ECG-gating acquisition techniques among all study population by the effective dose (ED) which is calculated from the DLP of the coronary scan. The effective radiation dose (ED) median was significantly lower in the prospective ECG-gating technique (7 msv) in comparison to retrospective ECG-gating technique (23 msv). We also compared the difference in radiation dose between MDCT 320 and 64 using retrospective ECG gating acquisition technique, the median (ED) was significantly lower in the 320 MI)CT technique (20 msv) in comparison to 64 MDCT (26 msv). The last comparison was the difference Of radiation dose between patients who underwent through MDCT 320 using two different techniques (prospective and retrospective), the median effective dose was lower in the prospective ECG-gating technique (7 msv) in comparison to retrospective ECG-gating technique (20 msv) this difference is also of high statistical significant value. Conclusion Prospective ECG-Gated CT coronary angiography protocol impressively reduces effective radiation doses in comparison to retrospective ECG-gated technique on 320 MDCT and is still sensitive for diagnosing significant coronary stenosis for patients with suspected CAD. Retrospective Coronary CT angiography can be performed with 320-MDCT with less radiation doses compared to 64-MDCT.

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