title: Fetal trans-apical stent delivery into the pulmonary artery: prospects for prenatal heart-valve implantation.
abstract: OBJECTIVE
  The purpose of this study was to assess the technical feasibility of a fetal trans-apical stent delivery into the pulmonary artery using a novel hybrid-intervention technique as a possible route for prenatal minimally invasive heart-valve-implantation approaches.
  
  
  METHODS
  Pregnant Pre-Alp sheep between 122 and 128 days' gestation (n = 3) underwent a midline laparotomy. The fetus was left in utero or partially externalized and its chest was opened via a left-sided minithoracotomy. The fetal heart was cannulated and a guide wire was introduced through the ductus arteriosus into the aorta. A 14-French delivery system was then mounted onto the guide wire and advanced to the landing zone in the pulmonary artery, where the stent was deployed. The position of the stent was confirmed using echocardiography, angiography as well as computed tomography.
  
  
  RESULTS
  The trans-apical implantation was successful in all animals. However, at necropsy in one animal, the stent was found to partly occlude one of the pulmonary valvular leaflets. Bleeding at the antero-apical incision occurred in all animals but could be managed without fetal demise. No fetal cardiopulmonary bypass was performed. In all animals, contrast angiography displayed normal perfusion of the pulmonary vasculature as well as the ductus arteriosus.
  
  
  CONCLUSIONS
  Our study demonstrates the principal technical feasibility of a prenatal stent delivery into the pulmonary artery using a novel trans-apical hybrid-intervention technique. This approach demonstrates the first step towards possible future minimally invasive prenatal heart-valve-implantation procedures.
authors: Clinic for Cardiovascular Surgery and Department of Surgical Research, University Hospital of Zurich, Zurich, Switzerland.
authors: Benedikt
authors: B
authors: Weber
authors: Maximilian Y
authors: MY
authors: Emmert
authors: Luc
authors: L
authors: Behr
authors: Chad
authors: C
authors: Brokopp
authors: Thomas
authors: T
authors: Frauenfelder
authors: Oliver
authors: O
authors: Kretschmar
authors: Volkmar
authors: V
authors: Falk
authors: Simon P
authors: SP
authors: Hoerstrup
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D005315:Fetal Diseases / Q000601:surgery*; D005318:Fetal Heart / Q000000981:diagnostic imaging; D006330:Heart Defects, Congenital / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D011247:Pregnancy; D011651:Pulmonary Artery / Q000601:surgery*; D012756:Sheep; D015607:Stents; D014057:Tomography, X-Ray Computed