title: Twin-twin transfusion syndrome, coarctation of the aorta and hypoplastic aortic arch: a case series report.
abstract: OBJECTIVE
  The twin-twin transfusion syndrome (TTTS) complicates 10-30% of monochorionic pregnancies. The incidence of pulmonary stenosis and endocardial fibroelastosis is especially high in the recipient twin. We report a novel finding of four cases of coarctation of the aorta and hypoplastic aortic arch in the donor to raise awareness of cardiac lesions in twins affected by TTTS.
  
  
  METHODS
  Retrospective review of both neonatal database and mortality data from 2002 to 2007 with cross-validation from the local tertiary cardiology unit data (1998-2006) to identify children presenting with coarctation who were also twins.
  
  
  RESULTS
  We identified four monochorionic twin pairs affected by the TTTS, delivered between 25 weeks and 36 weeks' gestation, where the donor was found to have coarctation of the aorta or a hypoplastic aortic arch. In addition, two of the four recipients also had cardiac abnormalities. There was a high mortality rate of 30% for both twins, and a high morbidity rate, especially for neurological sequelae.
  
  
  CONCLUSIONS
  We believe that the types of abnormalities seen may be explained by the altered fetal blood flow and haemodynamics in TTTS. Given the increased prevalence of congenital heart disease in TTTS, with an increased risk of coarctation in the donor twin and pulmonary stenosis in the recipient, intra-uterine surveillance and a post-natal comprehensive cardiac assessment for both twins is warranted.
authors.affiliation: Newborn Service, Auckland City Hospital, Auckland, New Zealand.
authors.forename: Jutta
authors.initials: J
authors.lastname: van den Boom
authors.forename: Malcolm
authors.initials: M
authors.lastname: Battin
authors.forename: Tim
authors.initials: T
authors.lastname: Hornung
mesh_terms: D001017:Aortic Coarctation / Q000453:epidemiology* / Q000209:etiology; D004374:Ductus Arteriosus, Patent / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005330:Fetofetal Transfusion / Q000453:epidemiology*; D006330:Heart Defects, Congenital / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D011247:Pregnancy; D015995:Prevalence; D011666:Pulmonary Valve Stenosis / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D014430:Twins, Monozygotic