Purpose
Coronary computed tomography angiography (CCTA) has evolved to an unprecedented rate during the last decade.
It has become an effective and accurate tool for cardiac imaging with a growing list of clinical indications [1].
The detection of coronary disease in the investigation of atypical chest pain patients at low and intermediate risk with non-contributory functional tests is one of the main indications.
CCTA is also useful for acute chest pain patients at low risk with normal electrocardiogram (ECG) and enzymatic cycle (Fig.1).
Cardiac CT has...
Methods and materials
A retrospective survey was carried out in 2013 within 8 academic and non–academic French hospitals specialized in cardiac imaging.
460 CCTA performed in a 3 months period were collected.
The CT scanners of these centres were 64 to 320-detectors CT scanners from different manufacturers using different routine protocols,
taking differently into account the patient BMI (Table 1).
Prospective ECG-gating mode and iterative reconstruction algorithm were available on six of them.
Table 1. CT scanners of the 8 centres included in this study
Centre
CT Scanner...
Results
The large gap in dose between the prospective and the retrospective ECG gating modes required to analyse separately the CTDIvol and DLP for the two modes.
Mean values are presented in table 2 for each centre.
Table 2.
Mean values of CTDIvol and DLP per centre,
for CCTA performed with prospective and retrospective ECG-gating modes
Centre
A
B
C
D
E
F
G
H
Retrospective mode
n
16
49
49
49
49
49
mean CTDIvol ± SD (mGy)
34±13
64±9
25±7
38±14
21±11
26±15
mean...
Conclusion
Prospective ECG gating and IR are efficient dose reduction techniques in CCTA but they do not exempt the centres from a more global optimization approach.
Whatever the brand and the generation of CT scanner,
a significant dose optimization is possible,
using simple methods such as tube current and voltage adaptation to the BMI.
This study confirms the large variability in patient doses in CCTA,
underlining the need for cardiac acquisition protocols optimization.
The availability of National DRLs should be mandatory in this setting.
Personal information
F.
Mafalanka.
Master Degree in Medical Physics.
Institut de Radioprotection et de Sûreté Nucléaire.
Fontenay-aux-Roses.
France
JL.
Réhel.
Radiation Protection Ingenieer.Institut de Radioprotection et de Sûreté Nucléaire.
Fontenay-aux-Roses.
France
D.
Pesenti-Rossi (MD).
Clinique Ambroise Paré.
Neuilly-sur-Seine.
France
LP.
Christiaens (Med.
Prof).
Service de cardiologie.
CHU Poitiers.
France
R.
Convers-Domart (MD).
Service de cardiologie.
Hopital Mignot.
Le Chesnay.
France
P.
Ou (MD).
Service d'imagerie médicale.
CHU Bichat.
Paris.
France
E.
Schouman-Clayes (Med.
Prof).Service d'imagerie médicale.
CHU Bichat.
Paris.
France
M.
Sirol (MD).
Service de cardiologie.
Hôpital...
References
[1] Lin EC,
Bredeweg RP,
Sicuro PL et al.
Coronary CTAngiography. http://emedicine.medscape.com/article/1603072-overview#showall.
Achieved 27 December 2013.
[2] Hammas S,
Amato A,Amabile N,Pesenti Rossi D andCaussin C.
Use of multislice computed tomography angiography in percutaneous coronary intervention.
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Cardiol.
2011;3(4):417-419.
[3] Pesenti Rossi D,
Chouli M,
Gharbi M,
Habib Y,
Brenot P,
Angel CY,
Paul JF,
Capderou A,
Lancelin B,
Caussin C.
Coronary aorto-ostial analysed by Multi-Slice Computed Tomography: A new tool for PCI?” EuroIntervention.
2011; 6(6):717-21.
[4] Pesenti Rossi D,
Baron N,
Georges J-L,
Livarek...