title: Right ventricular outflow tract enlargement prior to pulmonary valve replacement is associated with poorer structural and functional outcomes, in adults with repaired Tetralogy of Fallot.
abstract: BACKGROUND
  Pulmonary valve replacement (PVR) is commonly performed late after Tetralogy of Fallot (TOF) repair. We examined the effects of PVR on cardiac structure, function and exercise capacity in adults with repaired TOF.
  
  
  METHODS
  Eighteen adult patients with repaired TOF and severe pulmonary regurgitation (PR) with right ventricular (RV) dilatation requiring PVR for clinical reasons (age; 25±8 years) were recruited to undergo cardiac MRI (1.5T) and cardiopulmonary exercise testing before and 14±3 months after PVR.
  
  
  RESULTS
  Reduced indexed RV end-diastolic volume (RVEDVi; 186±32mL/m(2) pre-op vs 114±20mL/m(2) post-op, p<0.001) was observed after PVR. "Normalisation" of RVEDVi (≤108mL/m(2)) was achieved in only seven of 18 patients. Pre-PVR RVEDVi correlated with post-operative change in RVEDVi (change=-72.1±20.4mL/m(2), r=-0.815, p<0.001). Exercise capacity remained high-normal post-PVR (% predicted maximal workload: 93±16% vs 91±12%, p=0.5). Regional RV volumes were assessed; RV outflow tract (RVOT) volumes were compared to the RV muscular corpus. Large pre-PVR RVOT volumes correlated negatively with post-surgical RV ejection fraction, peak VO2 and delta VO2 at anaerobic threshold (p<0.05 for all).
  
  
  CONCLUSIONS
  Normalisation of RV volume is unlikely to be achieved above a pre-PVR RVEDVi of 165mL/m(2) or more. In particular, an enlarged RVOT prior to PVR predicts suboptimal structural and functional outcomes.
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Royal Prince Alfred Hospital, Department of Cardiology, Sydney, Australia. Electronic address: shamus.omeagher@sswahs.nsw.gov.au.
authors.forename: Shamus
authors.initials: S
authors.lastname: O'Meagher
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; The Children's Hospital at Westmead, Department of Cardiology, Sydney, Australia.
authors.forename: Madhusudan
authors.initials: M
authors.lastname: Ganigara
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Royal Prince Alfred Hospital, Department of Respiratory and Sleep Medicine, Sydney, Australia.
authors.forename: Phillip
authors.initials: P
authors.lastname: Munoz
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Westmead Hospital, Department of Cardiology, Sydney, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Tanous
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Westmead Hospital, Department of Cardiology, Sydney, Australia.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Chard
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Royal Prince Alfred Hospital, Department of Cardiology, Sydney, Australia.
authors.forename: David S
authors.initials: DS
authors.lastname: Celermajer
authors.affiliation: The University of Sydney, Faculty of Medicine, Sydney, Australia; Royal Prince Alfred Hospital, Department of Cardiology, Sydney, Australia.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Puranik
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011664:Pulmonary Valve / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D011665:Pulmonary Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D011859:Radiography; D013771:Tetralogy of Fallot / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery
keywords: Adult congenital heart disease; Cardiac magnetic resonance imaging; Cardiopulmonary exercise test; Pulmonary valve replacement; Right ventricular dilatation; Tetralogy of Fallot