title: Atrial Function after the Atrial Switch Operation for Transposition of the Great Arteries: Comparison with Arterial Switch and Normals by Cardiovascular Magnetic Resonance.
abstract: OBJECTIVE
  The atria serve as reservoir, conduit, and active pump for ventricular filling. The performance of the atrial baffles after atrial switch repair for transposition of the great arteries may be abnormal and impact the function of the systemic right ventricle. We sought to assess atrial function in patients after atrial repair in comparison to patients after arterial switch repair (ASO) and to controls.
  
  
  METHODS
  Using magnetic resonance imaging, atrial volumes and functional parameters were measured in 17 patients after atrial switch repair, 9 patients after ASO and 10 healthy subjects.
  
  
  RESULTS
  After the atrial switch operation, the maximum volume of the pulmonary venous atrium was significantly enlarged, but not of the systemic venous atrium. In both patients groups, independently from the surgical technique used, the minimum atrial volumes were elevated, which resulted in a decreased total empting fraction compared with controls (P < .01). The passive empting volume was diminished for right atrium, but elevated for left atrium after atrial switch and normal for left atrium after ASO; however, the passive empting fraction was diminished for both right atrium and left atrium after both operations (P < .01). The active empting volume was the most affected parameter in both atria and both groups and active empting fractions were highly significantly reduced compared with controls.
  
  
  CONCLUSIONS
  Atrial function is abnormal in all patients, after atrial switch and ASO repair. The cyclic volume changes, that is, atrial filling and empting, are reduced when compared with normal subjects. Thus, the atria have lost part of their capacity to convert continuous venous flow into a pulsatile ventricular filling. The function of the pulmonary venous atrium, acting as preload for the systemic right ventricle, after atrial switch is altered the most.
authors.affiliation: Division of Cardiology, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.|Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.
authors.forename: Francesca D
authors.initials: FD
authors.lastname: Franzoso
authors.affiliation: Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.|Department of Gynecology and Obstetrics, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Wohlmuth
authors.affiliation: Department of Cardiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Greutmann
authors.affiliation: Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.|Department of Diagnostic Imaging, University Children's Hospital Zurich, Zurich, Switzerland.
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Kellenberger
authors.affiliation: Division of Cardiology, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.|Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.|Department of Cardiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Angela
authors.initials: A
authors.lastname: Oxenius
authors.affiliation: Division of Cardiology, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.|Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Voser
authors.affiliation: Division of Cardiology, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland. Emanuela.valsangiacomo@kispi.uzh.ch.|Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland. Emanuela.valsangiacomo@kispi.uzh.ch.
authors.forename: Emanuela R
authors.initials: ER
authors.lastname: Valsangiacomo Buechel
mesh_terms: D000293:Adolescent; D000328:Adult; D000069278:Arterial Switch Operation / Q000379:methods*; D016280:Atrial Function, Right / Q000502:physiology*; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D011184:Postoperative Period; D012372:ROC Curve; D012039:Regional Blood Flow; D014188:Transposition of Great Vessels / Q000175:diagnosis / Q000601:surgery*; D016278:Ventricular Function, Right / Q000502:physiology; D055815:Young Adult
keywords: Atrial Function; Atrial Switch Operation; Systemic Right Ventricle; Transposition of the Great Arteries; Venous Baffle