title: High-pitch dual-source CT angiography of the aortic valve-aortic root complex without ECG-synchronization.
abstract: OBJECTIVE
  To compare image quality and radiation dose of high-pitch computed tomography angiography(CTA) of the aortic valve-aortic root complex with and without prospective ECG-gating compared to a retrospectively ECG-gated standard-pitch acquisition.
  
  
  METHODS
  120 patients (mean age 68±13 years) were examined using a 128-slice dual-source CT system using prospectively ECG-gated high-pitch (group A; n=40), non-ECG-gated high-pitch (group B; n=40) or retrospectively ECG-gated standard-pitch (C; n=40) acquisition techniques. Image quality of the aortic root, valve and ascending aorta including the coronary ostia was assessed by two independent readers. Image noise was measured, radiation dose estimates were calculated.
  
  
  RESULTS
  Interobserver agreement was good(κ=0.64-0.78). Image quality was diagnostic in 38/40 patients (group A), 37/40(B) and 38/40(C) with no significant difference in number of patients with diagnostic image quality among all groups (p=0.56). Significantly more patients showed excellent image quality in group A compared to groups B and C (each, p<0.01). Average image noise was significantly different between all groups (p<0.05). Mean radiation dose estimates in groups A and B (each; 2.4±0.3 mSv) were significantly lower compared to group C (17.5±4.4 mSv; p<0.01).
  
  
  CONCLUSIONS
  High-pitch dual-source CTA provides diagnostic image quality of the aortic valve-aortic root complex even without ECG-gating at 86% less radiation dose when compared to a standard-pitch ECG-gated acquisition.
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland. christoph.karlo@usz.ch
authors.forename: Christoph
authors.initials: C
authors.lastname: Karlo
authors.forename: Sebastian
authors.initials: S
authors.lastname: Leschka
authors.forename: Robert Paul
authors.initials: RP
authors.lastname: Goetti
authors.forename: Gudrun
authors.initials: G
authors.lastname: Feuchtner
authors.forename: Lotus
authors.initials: L
authors.lastname: Desbiolles
authors.forename: Paul
authors.initials: P
authors.lastname: Stolzmann
authors.forename: Andre
authors.initials: A
authors.lastname: Plass
authors.forename: Volkmar
authors.initials: V
authors.lastname: Falk
authors.forename: Borut
authors.initials: B
authors.lastname: Marincek
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.forename: Stephan
authors.initials: S
authors.lastname: Baumüller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging*; D001027:Aortography; D055424:Cardiac-Gated Imaging Techniques; D017023:Coronary Angiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed