title: Melody transcatheter valve: Histopathology and clinical implications of nine explanted devices.
abstract: OBJECTIVE
  We examined interventionally implanted valved Melody conduits after surgical explantation by means of histology and immunohistochemistry and matched these findings with clinical data in order to assess in vivo biocompatibility and to identify risk factors for graft failure.
  
  
  METHODS
  9 Melody valves had been implanted in 8 patients (pulmonary n = 7, tricuspid position n = 1). Indication for explantation included significant obstruction in 7 patients and valve insufficiency in 1 patient. 4 of 8 patients had suffered from endocarditis. Mean interval between implantation and explantation was 3.2 (1.8-5.2) years. All explants were worked up using a uniform protocol with fixation in formalin and embedding in methylmethacrylate.
  
  
  RESULTS
  All but one valve of the explanted Melody grafts were thin and histologically intact without any pathological findings. Complete neo-endothelialization could be demonstrated by means of immunohistochemistry. All 4 Melody valves from patients with endocarditis showed dense granulocytic infiltrations, 3 of these showed thrombotic material within the valves.
  
  
  CONCLUSIONS
  This report covers the first series of explanted Melody valves from humans applying a uniform protocol for histopathological examination. Good biocompatibility of the Melody valves could be demonstrated after a mid-term follow-up. Factors for graft failure included endocarditis, outgrowth, and residual stenosis. These findings may have significant implications for the implant procedure as well as care of the patients during long-term follow-up.
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University, Goettingen, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Schneider
authors.affiliation: Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center at the Technische Universitaet Muenchen, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Vogt
authors.affiliation: Leiden University Medical Center, Department of Pediatric Cardiology, Netherlands.
authors.forename: Regina
authors.initials: R
authors.lastname: Boekenkamp
authors.affiliation: Department of Cardiovascular Surgery, German Heart Center at the Technische Universitaet Muenchen, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Hoerer
authors.affiliation: Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center at the Technische Universitaet Muenchen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Eicken
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University, Goettingen, Germany.
authors.forename: Rudi
authors.initials: R
authors.lastname: Foth
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University, Goettingen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kriebel
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University, Goettingen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Paul
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University, Goettingen, Germany. Electronic address: msigler@gwdg.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Sigler
mesh_terms: D000293:Adolescent; D000328:Adult; D001705:Bioprosthesis; D006328:Cardiac Catheterization / Q000379:methods; D002648:Child; D020878:Device Removal; D019544:Equipment Failure Analysis / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000473:pathology / Q000601:surgery; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D011475:Prosthesis Failure; D011665:Pulmonary Valve Insufficiency / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D012086:Reoperation; D012189:Retrospective Studies; D012494:Sampling Studies; D013997:Time Factors; D014463:Ultrasonography; D055815:Young Adult
keywords: Catheterization; Congenital heart defects; Histopathology; Implantable heart valves