title: Percutaneous valve stent insertion to correct the pulmonary regurgitation: an animal feasibility study.
abstract: BACKGROUND
  Pulmonary regurgitation leads to progressive right ventricular dysfunction, susceptibility to arrhythmias, and sudden cardiac death. Percutaneous valve replacement has been developed in recent years, providing patients with an alternative option. Percutaneous pulmonary valve replacement has been recently introduced into clinical practice. The goal of this study was to evaluate the feasibility of percutaneous valve stent insertion to correct the pulmonary regurgitation in sheep using a cup-shaped valve stent.
  
  
  METHODS
  Pulmonary regurgitation was created by percutaneous cylindrical stent insertion in native pulmonary annulus of 8 sheep. One month after the initial procedure, the sheep with previous cylindrical stent implanted underwent the same implantation procedure of pulmonary valve stent. The valve stent consisted of a cup-shaped stent and pericardial valves. Hemodynamic assessments of the bioprosthetic pulmonary valve were obtained by echocardiography at immediately post-implant and at 2 months follow up.
  
  
  RESULTS
  Successful transcatheter cylindrical stent insertion was performed in 7 sheep but failed in 1 sheep because the cylindrical stent was released to right ventricle outflow tract. After one month the 7 sheep with pulmonary regurgitation underwent valve stent implantation successfully. Echocardiography confirmed the stents were in desired position during the follow-up. No evidence of pulmonary valve insufficiency occurred in any animals. Echocardiography showed all heart function markers were normal.
  
  
  CONCLUSIONS
  Percutaneous cylindrical stent insertion to induce significant pulmonary regurgitation in sheep was feasible, simple and reproducible. Percutaneous pulmonary valve stent implantation can reduce pulmonary regurgitation in a sheep model. Further development of animal model and clinical trials are warranted.
authors.affiliation: Department of Cardiology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Bai
authors.forename: Gang-Jun
authors.initials: GJ
authors.lastname: Zong
authors.forename: Hai-Bing
authors.initials: HB
authors.lastname: Jiang
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Wu
authors.forename: Xian-Xian
authors.initials: XX
authors.lastname: Zhao
authors.forename: Yong-Wen
authors.initials: YW
authors.lastname: Qin
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D008297:Male; D011665:Pulmonary Valve Insufficiency / Q000601:surgery*; D012756:Sheep