title: Fetal stenting of the atrial septum: technique and initial results in cardiac lesions with left atrial hypertension.
abstract: BACKGROUND
  Hypoplastic left heart syndrome with a highly restrictive or intact atrial septum (HLHS-RAS) has a very high mortality. Fetal left atrial (LA) hypertension results in abnormal lung development with lymphangiectasia and pulmonary vein muscularization. We report our initial experience with percutaneous ultrasound-guided stenting of the fetal atrial septum to decompress the LA.
  
  
  METHODS
  Retrospective review of fetuses with HLHS-RAS or a variant that underwent active perinatal management from 2000 to 2012.
  
  
  RESULTS
  Ten fetuses were identified. Two died in utero (33, 29 weeks). Four required the urgent creation of an atrial communication immediately after birth but died subsequently (5-54 days). Four fetuses (28-36 weeks) underwent percutaneous stenting of the atrial septum, with ultrasound guidance and intravenous maternal sedation. Elevated LA pressure, pulmonary vein dilation and MRI estimated pulmonary perfusion all improved after stenting. Three of four stented fetuses were delivered vaginally. Atrial septectomy was performed within 48 h of delivery to ensure complete LA decompression, rather than for hypoxemia. Intraoperative lung biopsy demonstrated muscularized pulmonary veins and lymphangiectasia in all four. Two fetuses developed stent stenosis in utero and died after birth, from pulmonary hypertension and sepsis respectively. Two are alive, representing an improved outcome over our previous experience (p=0.03).
  
  
  CONCLUSIONS
  Fetal atrial septal stenting is feasible without maternal complications and allows vaginal delivery of a more stable neonate. Fetal LA decompression ameliorates rather than reverses lung injury, and is one component of an approach that may improve survival in HLHS-RAS.
authors.affiliation: Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, Canada. Electronic address: rajiv.chaturvedi@sickkids.ca.
authors.forename: Rajiv R
authors.initials: RR
authors.lastname: Chaturvedi
authors.forename: Greg
authors.initials: G
authors.lastname: Ryan
authors.forename: Michael
authors.initials: M
authors.lastname: Seed
authors.forename: Glen
authors.initials: G
authors.lastname: van Arsdell
authors.forename: Edgar T
authors.initials: ET
authors.lastname: Jaeggi
mesh_terms: D006328:Cardiac Catheterization; D006348:Cardiac Surgical Procedures / Q000379:methods*; D015150:Echocardiography, Doppler; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging / Q000601:surgery*; D005500:Follow-Up Studies; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000196:embryology / Q000601:surgery*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000196:embryology / Q000601:surgery*; D018636:Hypoplastic Left Heart Syndrome / Q000000981:diagnostic imaging / Q000196:embryology / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D015607:Stents; D016216:Ultrasonography, Prenatal
keywords: Fetal therapy; Hypoplastic left heart syndrome; Intact atrial septum; Pulmonary hypertension; Stents