title: Right ventricular mechanics in adults after surgical repair of tetralogy of fallot: insights from three-dimensional speckle-tracking echocardiography.
abstract: BACKGROUND
  The clinical relevance of evaluating right ventricular (RV) myocardial deformation in congenital heart disease is increasingly recognized. The aim of this study was to explore, using three-dimensional (3D) speckle-tracking echocardiography, RV mechanics in terms of 3D global area strain and mechanical dyssynchrony in adults with repaired tetralogy of Fallot.
  
  
  METHODS
  Twenty patients (12 men) aged 24.7 ± 8.6 years and 22 age-matched controls (11 men) were studied. Global RV peak area strain and area strain-derived systolic dyssynchrony index (SDI) were determined using 3D speckle-tracking echocardiography. RV end-diastolic volume and end-systolic volume, ejection fraction (EF), and pulmonary regurgitation fraction were measured in patients using cardiac magnetic resonance.
  
  
  RESULTS
  Coefficients of variation for intraobserver and interobserver measurements of RV global area strain were 6.1% and 7.9%, respectively, and those for SDI were 7.6% and 10.1%, respectively. Compared with controls, patients had significantly lower global area strain (P = .005) and greater SDI (P = .008). The prevalence of RV mechanical dyssynchrony (SDI > control mean + 2 SDs) in patients was 30%. In patients, global area strain correlated inversely with SDI (r = -0.42, P = .04), RV end-diastolic volume (r = -0.48, P = .032), and RV end-systolic volume (r = -0.48, P = .031) and positively with EF (r = -0.51, P = .02), while RV SDI correlated positively with RV end-systolic volume (r = 0.55, P = .012), pulmonary regurgitation fraction (r = 0.54, P = .031), and QRS duration (r = 0.51, P = .022) and negatively with RV EF (r = -0.62, P = .004). Multivariate analysis showed that RV EF (β = 0.22, P = .048) was a significant correlate of global area strain in patients.
  
  
  CONCLUSIONS
  In adults after tetralogy of Fallot repair, 3D RV deformation is impaired in association with RV dyssynchrony, volume overloading, and reduced EF.
authors: Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors: Hong-kui
authors: HK
authors: Yu
authors: Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors: Shu-juan
authors: SJ
authors: Li
authors: Department of Radiology, Queen Mary Hospital, Hong Kong, China.
authors: Janice J K
authors: JJ
authors: Ip
authors: Department of Radiology, Queen Mary Hospital, Hong Kong, China.
authors: Wendy W M
authors: WW
authors: Lam
authors: Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors: Sophia J
authors: SJ
authors: Wong
authors: Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. Electronic address: xfcheung@hkucc.hku.hk.
authors: Yiu-fai
authors: YF
authors: Cheung
mesh_terms: D000328:Adult; D006348:Cardiac Surgical Procedures; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D019651:Plastic Surgery Procedures; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013318:Stroke Volume; D013771:Tetralogy of Fallot / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D016896:Treatment Outcome; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D055815:Young Adult
keywords: 3D speckle-tracking; Mechanics; Right ventricle; Tetralogy of Fallot