BACKGROUND: With the thrombogenic tendency and permanent implant nature of metallic stents, synthetic polymers have been proposed as candidate materials for stents and local drug delivery designs. We investigated the biocompatibility of several synthetic polymers after experimental placement in the coronary artery. METHODS AND RESULTS: Five different biodegradable polymers (polyglycolic acid/polylactic acid [PGLA], polycaprolactone [PCL], polyhydroxybutyrate valerate [PHBV], polyorthoester [POE], and polyethyleneoxide/polybutylene terephthalate [PEO/ PBTP]) and three nonbiodegradable polymers (polyurethane [PUR], silicone [SIL], and polyethylene terephthalate [PETP]) were tested as strips deployed longitudinally across 90 degrees of the circumferential surface of coil wire stents. Appropriately sized polymer-loaded stents were implanted in porcine coronary arteries of 2.5- to 3.0-mm diameter. Four weeks after implantation, stent patency was assessed by angiography followed by microscopic examination of the coronary arteries. The biodegradable PCL, PHBV, and POE and the nonbiodegradable PUR and SIL evoked extensive inflammatory responses and fibrocellular proliferation (thickness of tissue response: 0.79 +/- 0.22, 1.12 +/- 0.01, 2.36 +/- 0.60, 1.24 +/- 0.36, and 1.43 +/- 0.15 mm, respectively). Less but still severe responses were observed for the biodegradable PGLA and PEO/PBTP (0.46 +/- 0.18 and 0.61 +/- 0.23 mm, respectively) and for the nonbiodegradable PETP (0.46 +/- 0.11 mm). CONCLUSIONS: An array of both biodegradable and nonbiodegradable polymers has been demonstrated to induce a marked inflammatory reaction within the coronary artery with subsequent neointimal thickening, which was not expected on the basis of in vitro tests. The observed tissue response may be attributable to a combination of parent polymer compound, biodegradation products, and possibly implant geometry.
BACKGROUND: With the thrombogenic tendency and permanent implant nature of metallic stents, synthetic polymers have been proposed as candidate materials for stents and local drug delivery designs. We investigated the biocompatibility of several synthetic polymers after experimental placement in the coronary artery. METHODS AND RESULTS: Five different biodegradable polymers (polyglycolic acid/polylactic acid [PGLA], polycaprolactone [PCL], polyhydroxybutyrate valerate [PHBV], polyorthoester [POE], and polyethyleneoxide/polybutylene terephthalate [PEO/ PBTP]) and three nonbiodegradable polymers (polyurethane [PUR], silicone [SIL], and polyethylene terephthalate [PETP]) were tested as strips deployed longitudinally across 90 degrees of the circumferential surface of coil wire stents. Appropriately sized polymer-loaded stents were implanted in porcine coronary arteries of 2.5- to 3.0-mm diameter. Four weeks after implantation, stent patency was assessed by angiography followed by microscopic examination of the coronary arteries. The biodegradable PCL, PHBV, and POE and the nonbiodegradable PUR and SIL evoked extensive inflammatory responses and fibrocellular proliferation (thickness of tissue response: 0.79 +/- 0.22, 1.12 +/- 0.01, 2.36 +/- 0.60, 1.24 +/- 0.36, and 1.43 +/- 0.15 mm, respectively). Less but still severe responses were observed for the biodegradable PGLA and PEO/PBTP (0.46 +/- 0.18 and 0.61 +/- 0.23 mm, respectively) and for the nonbiodegradable PETP (0.46 +/- 0.11 mm). CONCLUSIONS: An array of both biodegradable and nonbiodegradable polymers has been demonstrated to induce a marked inflammatory reaction within the coronary artery with subsequent neointimal thickening, which was not expected on the basis of in vitro tests. The observed tissue response may be attributable to a combination of parent polymer compound, biodegradation products, and possibly implant geometry.
Authors: D M Whelan; W J van der Giessen; S C Krabbendam; E A van Vliet; P D Verdouw; P W Serruys; H M van Beusekom Journal: Heart Date: 2000-03 Impact factor: 5.994
Authors: M Peuster; P Wohlsein; M Brügmann; M Ehlerding; K Seidler; C Fink; H Brauer; A Fischer; G Hausdorf Journal: Heart Date: 2001-11 Impact factor: 5.994
Authors: A L Lewis; T A Vick; A C Collias; L G Hughes; R R Palmer; S W Leppard; J D Furze; A S Taylor; P W Stratford Journal: J Mater Sci Mater Med Date: 2001 Oct-Dec Impact factor: 3.896
Authors: Dayane B Tada; Surinder Singh; Dattatri Nagesha; Evan Jost; Craig O Levy; Evin Gultepe; Robert Cormack; G Mike Makrigiorgos; Srinivas Sridhar Journal: Pharm Res Date: 2010-06-03 Impact factor: 4.200