title: Automated quantification of mitral inflow and aortic outflow stroke volumes by three-dimensional real-time volume color-flow Doppler transthoracic echocardiography: comparison with pulsed-wave Doppler and cardiac magnetic resonance imaging.
abstract: BACKGROUND
  The aim of this study was to compare the feasibility, accuracy, and reproducibility of automated quantification of mitral inflow and aortic stroke volumes (SVs) using real-time three-dimensional volume color-flow Doppler transthoracic echocardiography (RT-VCFD), with cardiac magnetic resonance (CMR) imaging as the reference method.
  
  
  METHODS
  In 44 patients (86% of the screened patients) without valvular disease, RT-VCFD, CMR left ventricular short-axis cines and aortic phase-contrast flow measurement and two-dimensional (2D) transthoracic echocardiography (TTE) were performed. Dedicated software was used to automatically measure mitral inflow and aortic SVs with RT-VCFD. CMR total SV was calculated using planimetry of short-axis slices and aortic SV by phase-contrast imaging. SVs by 2D TTE were computed in the conventional manner.
  
  
  RESULTS
  The mean age of the included patients was 40 ± 16 years, and the mean left ventricular ejection fraction was 61 ± 9%. Automated flow measurements were feasible in all study patients. Mitral inflow SV by 2D TTE and RT-VCFD were 85.0 ± 21.5 and 94.5 ± 22.0 mL, respectively, while total SV by CMR was 95.6 ± 22.7 mL (P < .001, analysis of variance). On post hoc analysis, mitral inflow SV by RT-VCFD was not different from the CMR value (P = .99), while SV on 2D TTE was underestimated (P = .001). The respective aortic SVs were 82.8 ± 22.3, 94.2 ± 22.3, and 93.4 ± 24.6 mL (P < .001). On post hoc analysis, aortic SV by RT-VCFD was not different from the CMR value (P = .99), while SV on 2D TTE was underestimated (P = .006). The interobserver variability for SV measurements was significantly worse for 2D TTE compared with RT-VCFD.
  
  
  CONCLUSIONS
  RT-VCFD imaging with an automated quantification algorithm is feasible, accurate, and reproducible for the measurement of mitral inflow and aortic SVs and is superior to manual 2D TTE-based measurements. The rapid and automated measurements make this technique practical in the clinical setting to measure and report SVs routinely where the acoustic window will allow it, which was 86% in our study.
authors: The Ohio State University, Columbus, Ohio 43210, USA.
authors: Paaladinesh
authors: P
authors: Thavendiranathan
authors: Shizhen
authors: S
authors: Liu
authors: Saurabh
authors: S
authors: Datta
authors: Michael
authors: M
authors: Walls
authors: Adrien
authors: A
authors: Nitinunu
authors: Thomas
authors: T
authors: Van Houten
authors: Nicholas A
authors: NA
authors: Tomson
authors: Laura
authors: L
authors: Vidmar
authors: Bogdan
authors: B
authors: Georgescu
authors: Yang
authors: Y
authors: Wang
authors: Seshadri
authors: S
authors: Srinivasan
authors: Nathalie
authors: N
authors: De Michelis
authors: Subha V
authors: SV
authors: Raman
authors: Thomas
authors: T
authors: Ryan
authors: Mani A
authors: MA
authors: Vannan
mesh_terms: D000328:Adult; D000465:Algorithms; D001011:Aorta / Q000000981:diagnostic imaging; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D018619:Echocardiography, Doppler, Pulsed / Q000379:methods*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*