title: Physiological Growth, Remodeling Potential, and Preserved Function of a Novel Bioprosthetic Tricuspid Valve: Tubular Bioprosthesis Made of Small Intestinal Submucosa-Derived Extracellular Matrix.
abstract: BACKGROUND
  Prosthetic valves currently used in children lack the ability to grow with the patient and often require multiple reoperations. Small intestinal submucosa-derived extracellular matrix (SIS-ECM) has been used successfully as a patch for repair in various tissues, including vessels, valves, and myocardium.
  
  
  OBJECTIVE
  This study sought to assess the remodeling potential of a tubular tricuspid valve (TV) bioprosthesis made of SIS-ECM by evaluating its growth, structure, and function in a growing ovine model.
  
  
  METHODS
  A total of 12 3-month-old lambs were studied for a period of 3 or 8 months. SIS-ECM TVs were placed in 8 lambs; conventional bioprosthetic valves and native valves (NV) were studied as controls. All lambs underwent serial echocardiography, measuring annulus diameter and valve and right ventricular function.
  
  
  RESULTS
  The SIS-ECM valves demonstrated an incremental increase in annular diameter similar to NV. SIS-ECM valve function was normal in 7 of 8; 1 valve had severe regurgitation due to a flail leaflet. Explanted SIS-ECM valves approximated native tissue in gross appearance. Histopathology demonstrated migration of resident mesenchymal cells into the scaffold and trilaminar ECM organization similar to an NV, without inflammation or calcification at 8 months. Ex vivo mechanical testing of SIS-ECM valve tissue showed normalization of the elastic modulus by 8 months.
  
  
  CONCLUSIONS
  In an ovine model, tubular SIS-ECM TV bioprostheses demonstrate "growth" and a cell-matrix structure similar to mature NVs while maintaining normal valve function. The SIS-ECM valve may provide a novel solution for TV replacement in children and adults.
authors: Division of Pediatric Cardiothoracic Surgery, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio. Electronic address: farhan.zafar@cchmc.org.
authors: Farhan
authors: F
authors: Zafar
authors: Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: Robert B
authors: RB
authors: Hinton
authors: Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: Ryan A
authors: RA
authors: Moore
authors: Division of Pediatric Cardiothoracic Surgery, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: R Scott
authors: RS
authors: Baker
authors: Division of Pediatric Cardiothoracic Surgery, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: Roosevelt
authors: R
authors: Bryant
authors: Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio.
authors: Daria A
authors: DA
authors: Narmoneva
authors: Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: Michael D
authors: MD
authors: Taylor
authors: Division of Pediatric Cardiothoracic Surgery, The Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio.
authors: David L
authors: DL
authors: Morales
mesh_terms: D000818:Animals; D001705:Bioprosthesis; D005109:Extracellular Matrix / Q000502:physiology; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D007421:Intestine, Small; D008297:Male; D012756:Sheep; D014261:Tricuspid Valve / Q000254:growth & development* / Q000473:pathology
keywords: extracellular matrix; pediatrics; surgery