title: Reproducibility of left and right ventricular mass measurements with cardiac CT.
abstract: BACKGROUND
  Cardiac CT provides volumetric data that enables characterization of the myocardium.
  
  
  OBJECTIVE
  We evaluated intraobserver, interobserver, and interstudy reproducibility of left ventricular (LV) and right ventricular (RV) mass quantification with cardiac CT.
  
  
  METHODS
  Thirty-eight patients who underwent cardiac CT twice within 365 days were included in this analysis. Functional reconstructions in 10% steps throughout the R-R interval and axial 1.5-mm sections were used. Semiautomatic contour detection was used to trace epicardial and endocardial borders in all cardiac phases for calculation of LV and RV ejection fraction, end-diastolic volume, end-systolic volume, cardiac output, stroke volume, and ventricular mass. For each study 2 observers measured LV and RV mass twice.
  
  
  RESULTS
  LV mass parameters derived from semiautomatic contour detection algorithm had excellent intraobserver (r = 1.00), interobserver (r = 0.99), and interstudy (r = 0.99) reproducibility (P < 0.0001). Average end-diastolic LV mass was 146.2 ± 42.9 g at the first CT study and 146.8 ± 44.4 g at the second study. For measuring RV mass, reproducibility was good on all levels (r = 0.78, r = 0.78, and r = 0.68, respectively, with an average end-diastolic mass of 25.7 ± 5.8 g at the first study and 24.4 ± 4.8 g at the second study.
  
  
  CONCLUSIONS
  Quantification of LV mass at cardiac CT with the threshold-based, region-growing semiautomatic segmentation analysis software evaluated here is highly observer independent and reproducible. This largely holds true for the estimation of RV mass as well; however, further improvements are needed to optimize reproducibility for RV mass quantification.
authors.affiliation: Heart and Vascular Center, Medical University of South Carolina, Charleston, SC 29401, USA.
authors.forename: Florian
authors.initials: F
authors.lastname: Schwarz
authors.forename: Richard
authors.initials: R
authors.lastname: Takx
authors.forename: U Joseph
authors.initials: UJ
authors.lastname: Schoepf
authors.forename: Yeong Shyan
authors.initials: YS
authors.lastname: Lee
authors.forename: Balazs
authors.initials: B
authors.lastname: Ruzsics
authors.forename: Eva Maria
authors.initials: EM
authors.lastname: Gassner
authors.forename: Salvatore
authors.initials: S
authors.lastname: Chiaramida
authors.forename: Thomas
authors.initials: T
authors.lastname: Henzler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002302:Cardiac Output; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017380:Hypertrophy, Right Ventricular / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012984:Software; D013318:Stroke Volume; D014057:Tomography, X-Ray Computed; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right