title: Ventricular interaction in children after repair of tetralogy of Fallot: a longitudinal echocardiographic study.
abstract: OBJECTIVE
  Progressive right ventricular (RV) dilation due to pulmonary regurgitation (PR) after repair of tetralogy of Fallot (TOF) may impair left ventricular (LV) filling. Our aim was to analyse long-term time courses of M-mode LV and RV measurements and to relate these to the degree of PR.
  
  
  RESULTS
  Retrospective longitudinal cohort of children (n = 88) after repair of TOF followed by serial echocardiography over 9 years. LV and RV diameters were expressed by z-scores based on normal paediatric reference values. Time courses of LV and RV diameter z-scores, degree of PR, and influence of co-variables were analysed using mixed regression models. LV diameter z-scores were significantly lowered before repair, increased after surgery, but fell again over time; thus, mean LV diameters were significantly lower than normal population means at all times. LV diameter z-scores correlated negatively with RV dilation and degree of PR. Notably, they were significantly higher in patients with previous shunts. After pulmonary valve replacement, LV diameter z-scores recovered to normal, whereas RV diameter z-scores remained abnormal.
  
  
  CONCLUSIONS
  Our results confirm progressive adverse RV-LV interaction in the long-term post-operative follow-up of TOF. The use of z-scores facilitated the analysis of time courses of LV and RV diameters.
authors.affiliation: Division of Paediatric Cardiology, Department of Paediatric and Adolescent Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
authors.forename: Katarina
authors.initials: K
authors.lastname: Zervan
authors.forename: Christoph
authors.initials: C
authors.lastname: Male
authors.forename: Thomas
authors.initials: T
authors.lastname: Benesch
authors.forename: Ulrike
authors.initials: U
authors.lastname: Salzer-Muhar