title: Assessment of intracardiac flow and vorticity in the right heart of patients after repair of tetralogy of Fallot by flow-sensitive 4D MRI.
abstract: OBJECTIVE
  To comprehensively and quantitatively analyse flow and vorticity in the right heart of patients after repair of tetralogy of Fallot (rTOF) compared with healthy volunteers.
  
  
  METHODS
  Time-resolved flow-sensitive 4D MRI was acquired in 24 rTOF patients and 12 volunteers. Qualitative flow evaluation was based on consensus reading of two observers. Quantitative analysis included segmentation of the right atrium (RA) and ventricle (RV) in a four-chamber view to extract volumes and regional haemodynamic information for computation of regional mean and peak vorticity.
  
  
  RESULTS
  Right heart intra-atrial, intraventricular and outflow tract flow patterns differed considerably between rTOF patients and volunteers. Peak RA and mean RV vorticity was significantly higher in patients (p = 0.02/0.05). Significant negative correlations were found between patients' maximum and mean RV and RA vorticity and ventricular volumes (p < 0.05). The main pulmonary artery (MPA) regurgitant flow was associated with higher RA and RV vorticity, which was significant for RA maximum and RV mean vorticity (p = 0.01/0.03).
  
  
  CONCLUSIONS
  The calculation of vorticity based on 4D flow data is an alternative approach to assess intracardiac flow changes in rTOF patients compared with qualitative flow visualization. Alterations in intracardiac vorticity could be relevant with regard to the development of RV dilation and impaired function.
  
  
  CONCLUSIONS
  • 4D flow MRI with vorticity calculation enables a novel approach to assess intracardiac flow. • Significantly higher intracardiac vorticity occurred in patients after repair of tetralogy of Fallot. • Regurgitant flow in the main pulmonary artery is associated with higher right heart vorticity.
authors.affiliation: Department of Congenital Heart Defects and Pediatric Cardiology (Heart Center, University of Freiburg), University Hospital Freiburg, Mathildenstr. 1, 79106, Freiburg, Germany. Daniel.Hirtler@uniklinik-freiburg.de.
authors.forename: Daniel
authors.initials: D
authors.lastname: Hirtler
authors.affiliation: Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Julio
authors.initials: J
authors.lastname: Garcia
authors.affiliation: Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Alex J
authors.initials: AJ
authors.lastname: Barker
authors.affiliation: Department of Radiology, University Childrens' Hospital Zurich, Zurich, Switzerland.
authors.forename: Julia
authors.initials: J
authors.lastname: Geiger
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003326:Coronary Circulation / Q000502:physiology; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D013771:Tetralogy of Fallot / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D055815:Young Adult
keywords: 4D flow MRI; Intracardiac flow; Right heart; Tetralogy of Fallot; Vorticity