title: Determining bronchial morphology for the purposes of segregating so-called heterotaxy.
abstract: Introduction Heterotaxy is a unique clinical entity in which lateralisation of the thoraco-abdominal organs is abnormal, typically with isomerism of the bronchial tree and atrial appendages. This study was carried out to determine whether routine clinical imaging such as chest radiographs, angiographic images, and CT/MRI can determine bronchial isomerism, and how sidedness of bronchial isomerism correlates with overall features anticipated in hearts with isomeric atrial appendages. Methods and results We identified 73 patients with heterotaxy, in whom imaging clearly demonstrated the bronchial tree, seen at our institution since 1998. We calculated bronchial angles and lengths using all the available imaging modalities to determine the presence and sidedness of bronchial isomerism. This was then compared with the anticipated presence of isomeric atrial appendages based on the overall clinical findings, as the appendages themselves had not specifically been imaged. The ratio of bronchial lengths revealed bronchial isomerism in all patients, with bronchial angles permitting distinction of right as opposed to left isomerism. We noted discordances between the identified bronchial isomerism and the presumed arrangement of the atrial appendages in nearly 20% of the patients in our cohort.
  
  
  CONCLUSIONS
  Routine clinical imaging with chest radiographs, angiographic imaging, and CT/MRI can determine the presence of bronchial isomerism in patients with so-called heterotaxy. Right as opposed to left isomerism can be distinguished based on bronchial angles. The finding of bronchial isomerism correlates well, but not totally, with the presumed isomerism of the atrial appendages as predicted from the identified intra-cardiac morphology.
authors.affiliation: 1Children's Hospital of Wisconsin,Division of Cardiology,Milwaukee,Wisconsin,United States of America.
authors.forename: Rohit S
authors.initials: RS
authors.lastname: Loomba
authors.affiliation: 1Children's Hospital of Wisconsin,Division of Cardiology,Milwaukee,Wisconsin,United States of America.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Pelech
authors.affiliation: 2Advocate Illinois Masonic Medical Center,Division of Radiology,Chicago, Illinois,United States of America.
authors.forename: Parinda H
authors.initials: PH
authors.lastname: Shah
authors.affiliation: 3Institute of Genetic Medicine,Newcastle University,Newcastle Upon Tyne,United Kingdom.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Anderson
mesh_terms: D001980:Bronchi / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D059446:Heterotaxy Syndrome / Q000000981:diagnostic imaging*; D006801:Humans; D007231:Infant, Newborn; D012189:Retrospective Studies
keywords: Bronchial morphology; CT; X-ray; heterotaxy; isomerism