title: Image quality on dual-source computed-tomographic coronary angiography.
abstract: Multi-detector CT reliably permits visualization of coronary arteries, but due to the occurrence of motion artefacts at heart rates >65 bpm caused by a temporal resolution of 165 ms, its utilisation has so far been limited to patients with a preferably low heart rate. We investigated the assessment of image quality on computed tomography of coronary arteries in a large series of patients without additional heart rate control using dual-source computed tomography (DSCT). DSCT (Siemens Somatom Definition, 83-ms temporal resolution) was performed in 165 consecutive patients (mean age 64 +/- 11.4 years) after injection of 60-80 ml of contrast. Data sets were reconstructed in 5% intervals of the cardiac cycle and evaluated by two readers in consensus concerning evaluability of the coronary arteries and presence of motion and beam-hardening artefacts using the AHA 16-segment coronary model. Mean heart rate during CT was 65 +/- 10.5 bpm; visualisation without artefacts was possible in 98.7% of 2,541 coronary segments. Only two segments were considered unevaluable due to cardiac motion; 30 segments were unassessable due to poor signal-to-noise ratio or coronary calcifications (both n = 15). Data reconstruction at 65-70% of the cardiac cycle provided for the best image quality. For heart rates >85 bpm, a systolic reconstruction at 45% revealed satisfactory results. Compared with earlier CT generations, DSCT provides for non-invasive coronary angiography with diagnostic image quality even at heart rates >65 bpm and thus may broaden the spectrum of patients that can be investigated non-invasively.
authors.affiliation: Department of Cardiology, Kerckhoff Heart Center, Benekestrasse 2 - 8, 61231, Bad Nauheim, Germany. j.rixe@kerckhoff-klinik.de
authors.forename: Johannes
authors.initials: J
authors.lastname: Rixe
authors.forename: Andreas
authors.initials: A
authors.lastname: Rolf
authors.forename: Guido
authors.initials: G
authors.lastname: Conradi
authors.forename: Albrecht
authors.initials: A
authors.lastname: Elsaesser
authors.forename: Helge
authors.initials: H
authors.lastname: Moellmann
authors.forename: Holger M
authors.initials: HM
authors.lastname: Nef
authors.forename: Georg
authors.initials: G
authors.lastname: Bachmann
authors.forename: Christian W
authors.initials: CW
authors.lastname: Hamm
authors.forename: Thorsten
authors.initials: T
authors.lastname: Dill
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*