title: Impact of a new motion-correction algorithm on image quality of low-dose coronary CT angiography in patients with insufficient heart rate control.
abstract: OBJECTIVE
  Prospective electrocardiogram (ECG) triggering allows coronary computed tomography angiography (CCTA) scanning with low radiation dose but requires heart rates below 63 beats/min. We assessed the impact of a novel vendor-specific motion-correction algorithm on image quality and interpretability of low-dose CCTA acquired despite insufficient heart rate control.
  
  
  METHODS
  In 40 patients undergoing CCTA for the assessment of known or suspected coronary artery disease who did not reach the target heart rate below 63 beats/min despite β-blockade before prospective low-dose scanning, the temporal acquisition window was increased (80 ms additional padding). The new algorithm detects and integrates vessel path and velocity from adjacent cardiac phases for motion correction. Two blinded observers assessed image quality on a 4-point Likert scale (1, nonevaluative; 2, reduced but evaluative; 3, good; and 4, excellent) and the fraction of interpretable segments (score 2 or more) using motion correction versus standard reconstruction.
  
  
  RESULTS
  Image reconstruction with motion correction resulted in an increased median coronary artery image quality score (excellent interobserver agreement, κ = 0.85) compared to standard reconstruction (3.4 vs. 3.0, P < .001). Consequently, motion-corrected reconstruction significantly improved the overall interpretability of coronary arteries (from 78% to 88%, P < .001). Estimated mean effective radiation dose was 2.3 ± 0.8 mSv.
  
  
  CONCLUSIONS
  A novel, vendor-specific, motion-corrected, reconstruction algorithm improves image quality and interpretability of prospectively ECG-triggered low-dose CCTA despite insufficient heart rate control.
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Tobias A
authors: TA
authors: Fuchs
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Julia
authors: J
authors: Stehli
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Svetlana
authors: S
authors: Dougoud
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Michael
authors: M
authors: Fiechter
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Bert-Ram
authors: BR
authors: Sah
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Ronny R
authors: RR
authors: Buechel
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Sacha
authors: S
authors: Bull
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland.
authors: Oliver
authors: O
authors: Gaemperli
authors: Department of Nuclear Medicine and Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, NUK C 42, CH-8091, Zurich, Switzerland. Electronic address: pak@usz.ch.
authors: Philipp A
authors: PA
authors: Kaufmann
mesh_terms: D000465:Algorithms; D016477:Artifacts; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009038:Motion; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011856:Radiographic Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Coronary CT angiography (CCTA); insufficient heart rate control; motion correction