title: Left atrial ligation alters intracardiac flow patterns and the biomechanical landscape in the chick embryo.
abstract: BACKGROUND
  Hypoplastic left heart syndrome (HLHS) is a major human congenital heart defect that results in single ventricle physiology and high mortality. Clinical data indicate that intracardiac blood flow patterns during cardiac morphogenesis are a significant etiology. We used the left atrial ligation (LAL) model in the chick embryo to test the hypothesis that LAL immediately alters intracardiac flow streams and the biomechanical environment, preceding morphologic and structural defects observed in HLHS.
  
  
  RESULTS
  Using fluorescent dye injections, we found that intracardiac flow patterns from the right common cardinal vein, right vitelline vein, and left vitelline vein were altered immediately following LAL. Furthermore, we quantified a significant ventral shift of the right common cardinal and right vitelline vein flow streams. We developed an in silico model of LAL, which revealed that wall shear stress was reduced at the left atrioventricular canal and left side of the common ventricle.
  
  
  CONCLUSIONS
  Our results demonstrate that intracardiac flow patterns change immediately following LAL, supporting the role of hemodynamics in the progression of HLHS. Sites of reduced WSS revealed by computational modeling are commonly affected in HLHS, suggesting that changes in the biomechanical environment may lead to abnormal growth and remodeling of left heart structures.
authors.forename: William J
authors.initials: WJ
authors.lastname: Kowalski
authors.forename: Nikola C
authors.initials: NC
authors.lastname: Teslovich
authors.forename: Prahlad G
authors.initials: PG
authors.lastname: Menon
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Tinney
authors.forename: Bradley B
authors.initials: BB
authors.lastname: Keller
authors.forename: Kerem
authors.initials: K
authors.lastname: Pekkan
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D002642:Chick Embryo; D003198:Computer Simulation; D003326:Coronary Circulation; D004195:Disease Models, Animal; D006325:Heart Atria / Q000196:embryology / Q000473:pathology; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000196:embryology* / Q000473:pathology; D008955:Models, Cardiovascular