title: Right ventricle three-dimensional echography in corrected tetralogy of fallot: accuracy and variability.
abstract: OBJECTIVE
  To evaluate right ventricular (RV) volume and ejection fraction (EF) in adult normal subjects and repaired tetralogy of Fallot (ToF) with 3D trans-thoracic echocardiography (3DE) and a semi-automatic border detection algorithm.
  
  
  RESULTS
  Fourteen healthy volunteers and 20 patients with repaired ToF (mean age 31 +/- 14) underwent 3DE and MRI within the same day. Right ventricular end-systolic volume (ESV) and end-diastolic volume (EDV) and EF were measured by two observers using 3DE and compared with MRI measurements. Intra- and interobserver variability of 3DE and agreement between both methods were evaluated using Bland-Altman analysis. Over or underestimation of 3DE in comparison to MRI was assessed using paired t-test. Intra- and interobserver variability of 3DE was excellent with intraclass coefficient of correlation (ICC) ranging from 0.85 to 0.99 and from 0.85 to 0.98, respectively. Three-dimensional echocardiography underestimated ESV and EDV (P < 0.001) but agreement between 3DE and MRI was excellent (ICC = 0.88 and 0.87, respectively). Ejection fraction was 47.7 +/- 7.8 with 3DE and 47.9 +/- 6.7 with MRI, agreement between both methods was good (ICC = 0.72).
  
  
  CONCLUSIONS
  Three-dimensional echocardiography combined to semi-automated quantification software shows fair agreement with MRI for RV volumes and EF measurement in patients with repaired ToF and adequate intra- and interobserver variability. These results suggest applicability for serial follow-up of patients with right heart congenital disease. However, the accuracy of 3DE echo diminishes with larger RV volumes, in part due to current difficulty to include the entire RV in the imaged sector. Technical progress in transducers beam geometry is likely to address this issue.
authors.affiliation: Service des Cardiopathies Congénitales de l'Enfant et de l'Adulte, CHU de Bordeaux, Pessac, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Iriart
authors.forename: Michel
authors.initials: M
authors.lastname: Montaudon
authors.forename: Stéphane
authors.initials: S
authors.lastname: Lafitte
authors.forename: Julie
authors.initials: J
authors.lastname: Chabaneix
authors.forename: Patricia
authors.initials: P
authors.lastname: Réant
authors.forename: Thomas
authors.initials: T
authors.lastname: Balbach
authors.forename: Helene
authors.initials: H
authors.lastname: Houle
authors.forename: François
authors.initials: F
authors.lastname: Laurent
authors.forename: Jean-Benoît
authors.initials: JB
authors.lastname: Thambo
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000502:physiology; D013771:Tetralogy of Fallot / Q000000981:diagnostic imaging* / Q000503:physiopathology