title: Doppler-derived flow pattern in the descending aorta does not predict systemic to pulmonary arterial collateral flow in patients with single ventricle palliation: a cross-sectional study.
abstract: BACKGROUND
  Children with single ventricle heart disease are at risk for developing systemic to pulmonary arterial collateral vessels that adversely impact short-term outcomes, although the effect on long-term outcomes remains unclear. Collateral flow (CollF) can be quantified using cardiac magnetic resonance (CMR) flow quantification. The velocity-time integral (VTI), obtained from spectral Doppler tracings, has been used in "runoff" lesions like aortic regurgitation to quantify insufficiency. We hypothesized that the VTI ratio of the proximal descending aorta (DAo) after cavopulmonary anastomosis (CPA) would estimate CollF.
  
  
  METHODS
  A retrospective cross-sectional study was conducted. Patients who had a superior CPA or total CPA and underwent CMR between April 2008 and December 2012 were included. Those with greater than trivial semilunar valve insufficiency or aortic arch obstruction were excluded. In a subset (n = 88), spectral Doppler tracings of the DAo were analyzed to determine the VTI ratio. In another subset (n = 112), CMR was used to determine the ratio of retrograde to antegrade flow in the DAo.
  
  
  RESULTS
  There was no linear correlation between VTI ratio and CollF (r (2) = .006, P = .46). There was a weakly positive correlation with CollF (r (2) = .07, P = .007) and the CMR measured ratio of retrograde to antegrade flow. Holodiastolic flow reversal by echo did not predict higher CollF (P = .40), but those with holodiastolic flow reversal by CMR had significantly higher CollF (P = .04).
  
  
  CONCLUSIONS
  The ratio of reverse to forward flow in the DAo as determined by Doppler echo does not accurately reflect CollF in children with single ventricle after CPA.
authors: Children's Hospital Colorado Heart Institute, University of Colorado School of Medicine, Aurora, CO, USA michael.dimaria@childrenscolorado.org.
authors: Michael V
authors: MV
authors: Di Maria
authors: Division of Pediatric Cardiology, The Cardiac Center, The Children's Hospital of Philadelphia, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors: Meryl S
authors: MS
authors: Cohen
authors: Division of Pediatric Cardiology, The Cardiac Center, The Children's Hospital of Philadelphia, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors: Matthew A
authors: MA
authors: Harris
authors: Division of Pediatric Cardiology, The Cardiac Center, The Children's Hospital of Philadelphia, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors: Mark A
authors: MA
authors: Fogel
authors: Division of Pediatric Cardiology, The Cardiac Center, The Children's Hospital of Philadelphia, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors: Kevin K
authors: KK
authors: Whitehead
mesh_terms: D000293:Adolescent; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000502:physiology* / Q000601:surgery; D001022:Aortic Valve Insufficiency / Q000503:physiopathology / Q000601:surgery; D001783:Blood Flow Velocity / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D003097:Collateral Circulation / Q000502:physiology; D003430:Cross-Sectional Studies; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D018610:Heart Bypass, Right / Q000379:methods; D006352:Heart Ventricles / Q000002:abnormalities* / Q000601:surgery; D006801:Humans; D007223:Infant; D008297:Male; D010166:Palliative Care / Q000379:methods; D011651:Pulmonary Artery / Q000002:abnormalities* / Q000601:surgery; D012189:Retrospective Studies
keywords: Fontan procedure; collateral circulation; congenital heart disease; velocity–time integral