Coronary computed tomography angiography with a consistent dose below 1 mSv using prospectively electrocardiogram-triggered high-pitch spiral acquisition.
OBJECTIVE
We evaluated the feasibility and image quality of a new scan mode for coronary computed tomography angiography (CTA) with an effective dose of less than 1 mSv.


RESULTS
In 50 consecutive patients (body weight <or= 100 kg, sinus rhythm <or=60 b.p.m. after pre-medication, coronary CTA was performed using a dual-source CT system with 2 x 128 x 0.6 mm collimation, 0.28 s rotation time, a pitch of 3.2 or 3.4, 100 kV tube voltage and current of 320 mA s. Data acquisition was prospectively triggered at 60% of the R-R interval and completed within one cardiac cycle. Image quality was evaluated using a four-point scale (1 = absence of any artefacts to 4 = uninterpretable). In all 50 patients, imaging was successful. Mean duration of data acquisition was 258 +/- 20 ms. Mean dose-length product was 62 +/- 5 mGy cm, the effective dose was 0.87 +/- 0.07 mSv (0.78-0.99 mSv). Of the 742 coronary artery segments, 94% had an image quality score of 1, 5.0% a score of 2, 0.9% a score of 3, and 4 segments (0.5%) were 'uninterpretable'.


CONCLUSIONS
In non-obese patients with a low and stable heart rate, prospectively ECG-triggered high-pitch spiral coronary CTA provides excellent image quality at a consistent dose below 1.0 mSv.
Achenbach
Stephan
S
Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany. stephan.achenbach@uk-erlangen.de
Marwan
Mohamed
M
Ropers
Dieter
D
Schepis
Tiziano
T
Pflederer
Tobias
T
Anders
Katharina
K
Kuettner
Axel
A
Daniel
Werner G
WG
Uder
Michael
M
Lell
Michael M
MM
D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000188:drug therapy; D017023:Coronary Angiography / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D011829:Radiation Dosage; D036542:Tomography, Spiral Computed / Q000379:methods*
D000889:Anti-Arrhythmia Agents