Publications by authors named "Jay M Reimer"

2 Publications

  • Page 1 of 1

Pediatric tubular pulmonary heart valve from decellularized engineered tissue tubes.

Biomaterials 2015 Sep 16;62:88-94. Epub 2015 May 16.

Department of Biomedical Engineering, University of Minnesota, USA; Department of Chemical Engineering and Material Science, University of Minnesota, USA. Electronic address:

Pediatric patients account for a small portion of the heart valve replacements performed, but a pediatric pulmonary valve replacement with growth potential remains an unmet clinical need. Herein we report the first tubular heart valve made from two decellularized, engineered tissue tubes attached with absorbable sutures, which can meet this need, in principle. Engineered tissue tubes were fabricated by allowing ovine dermal fibroblasts to replace a sacrificial fibrin gel with an aligned, cell-produced collagenous matrix, which was subsequently decellularized. Previously, these engineered tubes became extensively recellularized following implantation into the sheep femoral artery. Thus, a tubular valve made from these tubes may be amenable to recellularization and, ideally, somatic growth. The suture line pattern generated three equi-spaced leaflets in the inner tube, which collapsed inward when exposed to back pressure, per tubular valve design. Valve testing was performed in a pulse duplicator system equipped with a secondary flow loop to allow for root distention. All tissue-engineered valves exhibited full leaflet opening and closing, minimal regurgitation (<5%), and low systolic pressure gradients (<2.5 mmHg) under pulmonary conditions. Valve performance was maintained under various trans-root pressure gradients and no tissue damage was evident after 2 million cycles of fatigue testing.
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http://dx.doi.org/10.1016/j.biomaterials.2015.05.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4490908PMC
September 2015

Tubular heart valves from decellularized engineered tissue.

Ann Biomed Eng 2013 Dec 30;41(12):2645-54. Epub 2013 Jul 30.

Department of Biomedical Engineering, University of Minnesota, 7-114 NHH, 312 Church St SE, Minneapolis, MN, 55455, USA.

A novel tissue-engineered heart valve (TEHV) was fabricated from a decellularized tissue tube mounted on a frame with three struts, which upon back-pressure cause the tube to collapse into three coapting "leaflets." The tissue was completely biological, fabricated from ovine fibroblasts dispersed within a fibrin gel, compacted into a circumferentially aligned tube on a mandrel, and matured using a bioreactor system that applied cyclic distension. Following decellularization, the resulting tissue possessed tensile mechanical properties, mechanical anisotropy, and collagen content that were comparable to native pulmonary valve leaflets. When mounted on a custom frame and tested within a pulse duplicator system, the tubular TEHV displayed excellent function under both aortic and pulmonary conditions, with minimal regurgitant fractions and transvalvular pressure gradients at peak systole, as well as well as effective orifice areas exceeding those of current commercially available valve replacements. Short-term fatigue testing of one million cycles with pulmonary pressure gradients was conducted without significant change in mechanical properties and no observable macroscopic tissue deterioration. This study presents an attractive potential alternative to current tissue valve replacements due to its avoidance of chemical fixation and utilization of a tissue conducive to recellularization by host cell infiltration.
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http://dx.doi.org/10.1007/s10439-013-0872-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847912PMC
December 2013