title: Ventricular short-axis measurements in patients with pulmonary embolism: effect of ECG-gating on variability, accuracy, and risk prediction.
abstract: OBJECTIVE
  To assess prospectively the intra- and interobserver variability, accuracy, and prognostic value of right and left ventricular short-axis diameter (RVd and LVd) measurements for risk stratification in patients with pulmonary embolism (PE) using ECG-gated compared to non-gated CT.
  
  
  METHODS
  Sixty consecutive patients (33 women; mean age 58.7±10.3 years) with suspicion of PE underwent both non-gated and ECG-gated chest CT. RVd and LVd on four-chamber views and intra- and interobserver agreements were calculated for both protocols. RVd/LVd ratios were calculated and were related to 30-days adverse clinical events using receiver operating characteristics with area-under-the-curve (AUC) analyses.
  
  
  RESULTS
  Both inter- and intraobserver variability showed narrower limits of agreement for all measurements with ECG-gated as compared to non-gated CT. Diameter measurements were significantly lower using non-ECG-gated CT as compared to ECG-gated CT for RVd and LVd (both p<.05). The AUC for the RVd/LVd ratio from ECG-gated CT was significantly larger than that from non-gated CT (0.956, 95% CI: 0.768-0.999 versus 0.675, 95% CI: 0.439-0.860; p=.048).
  
  
  CONCLUSIONS
  RVd and LVd measurements from ECG-gated chest CT show less intra- and interobserver variability and more accurately reflect ventricular function. In our patient cohort ECG-gated chest CT allows better prediction of short-term outcome of patients with acute PE that needs to be validated in a larger outcome study.
authors: Institute of Diagnostic Radiology, University Hospital Zurich, Switzerland. hscheffel@partners.org
authors: Hans
authors: H
authors: Scheffel
authors: Paul
authors: P
authors: Stolzmann
authors: Sebastian
authors: S
authors: Leschka
authors: Lotus
authors: L
authors: Desbiolles
authors: Burkhardt
authors: B
authors: Seifert
authors: Borut
authors: B
authors: Marincek
authors: Hatem
authors: H
authors: Alkadhi
mesh_terms: D000368:Aged; D000792:Angiography / Q000379:methods; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011655:Pulmonary Embolism / Q000150:complications* / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology*